WO2006046147A1

WO2006046147A1 - Method for producing an acidic or neutral fresh milk product containing pieces of chocolate or a chocolate-like product, from a sweetened preparation

Info

Publication number: WO2006046147A1
Application number: PCT/IB2005/003556
Authority: WO
Inventors: Jean-Luc Rabault; Gérard PICK; Jean-François GRUEL
Original assignee: Compagnie Gervais Danone
Priority date: 2004-10-25
Filing date: 2005-10-24
Publication date: 2006-05-04
Also published as: EP1833303A1

Abstract

The present invention relates to a method for producing a sweetened aqueous preparation in which 8 to 30% by weight, advantageously 10 to 30% by weight, relative to the total weight of the preparation, of chocolate pieces are dispersed, which method comprises the following successive steps: a) pasteurization of the chocolate having a fat content of between 43 and 85% by weight, with a pasteurization strength Fz of between 6000 and 10 000 000 min or sterilization of the chocolate having a fat content between 43 and 85% by weight; b) cooling of the pasteurized of sterilized chocolate to a temperature of between 24 and 450 C; c) injection of the pasteurized or sterilized, cooled chocolate into a stream of pasteurized or sterilized, sweetened aqueous preparation having a temperature of between the freezing point of the sweetened aqueous preparation and 150 C; d) solidification of the pasteurized of sterilized chocolate injected; e) optionnaly cutting and mixing of the injected and solidified, pasteurized of sterilized chocolate in the pasteurized or sterilized, sweetened aqueous preparation; f) recovery of a sweetened aqueous preparation in which 8 to 30% by weight, relative to the total weight of the preparation, of chocolate pieces having a fat content of between 43 and 85% by weight are dispersed, said preparation being concerved at a temperature of less that 100 C for at least 3 weeks.

Description

TITLE: METHOD FOR PRODUCING AN ACIDIC OR NEUTRAL FRESH MILK PRODUCT CONTAINING PIECES OF CHOCOLATE OR A CHOCOLATE-LIKE PRODUCT, FROM A SWEETENED PREPARATION

The present invention relates to a method for producing a sweetened aqueous preparation containing pieces of chocolate or a chocolate-like product, and for preparing an acidic or neutral fresh milk product containing pieces of chocolate or a chocolate-like product, from this sweetened preparation.

The use of chocolate pieces in fresh milk products poses technical problems that are very different from those conventionally encountered in other food areas (chocolate making, confectionery, cookie production, ice cream, etc.) . In particular, the following problems are involved:

microbiological contamination: certain molds, yeast and vegetative bacteria naturally present in chocolate develop on contact with the water content of the fresh milk product. It is necessary to sterilize or pasteurize the chocolate; however, conventional pasteurization scales are ineffective on chocolate, because of its low Aw. In addition, the materials and methods used must be ultra- clean in order to prevent bacterial contamination or re- contamination; poor water resistance: a standard chocolate is soft after 5 hours in a yoghurt. However, it is necessary for the chocolate to keep its crunchiness .

Fresh milk products that contain pieces of unpasteurized chocolate (conventional chips, filled or not filled) are known in the prior art. However, in this case, preserving agents must be used or the shelf-lives of these milk products are short (< 12 days) . Zentis patent application EP 976 333 describes chocolate pieces (chips) obtained by crystallization of the chocolate upon contact with a cold gas (and not with an aqueous liquid) . These chocolate pieces can then be used as milk product additives. However, this method is expensive (in terms of investment and operating costs: the crystallization of the chocolate is carried out in a tower at a negative temperature of between -40 and -120⁰C, in order for it to be very rapid) and complex and is only available in a single factory in the world (Germany) . In addition, the chocolate pieces can be more readily contaminated before they are mixed with the fresh milk product . That patent does not deal with the microbiological aspect, in particular how to prevent recontamination during the steps in which the chocolate is crystallized and mixed with the sweetened preparation. Now, it is easier to maintain the sterilized or pasteurized state of the chocolate by confining the crystallization of the chocolate in a closed chamber (piping or tank) , than by crystallizing it in contact with the air or with a gas.

Patent application WO 00/70960 describes a solid chocolate or chocolate-like product, advantageously in the form of grains, that can be brought into contact with a wet mass such as a milk base. However, the chocolate grains are not prepared and added to the milk base via a sweetened aqueous preparation. Standard chocolate (i.e. chocolate which has not undergone thermal decontamination) is contaminated; now, nothing is suggested with regard to the need to pasteurize or sterilize the chocolate in order to prevent microbiological problems due to the contact with the fresh milk products. Furthermore, nothing is indicated regarding the manner in which this pasteurized state can be maintained until the product reaches the consumer, nor even until the product is packaged. Patent application EP 615 692 describes a method of crystallizing chocolate by injection into a neutral cold dairy mousse, followed by milling of the band of chocolate obtained. However, this method requires the use of a very bitter chocolate (between 1 and 10% by weight of sugar, advantageously between 1 and 3% by weight of sugar) , i.e. not very sweetened, the product obtained therefore not being very satisfactory for the consumer. Moreover, in order to mask this bitterness as much as possible, it is necessary to limit the size of the chocolate particles

(between 1 and 4 mm) . In addition, the method described requires investing in a complete production line for each mousse metering device in each factory. Furthermore, any interruption in the production of sterilized chocolate/injection stops the production of the milk product containing chocolate pieces. Finally_/ there is no time to validate the microbiology of the chocolate before it is used in production and introduced into the milk base (risk of having to discard a large amount of finished product in the event of contamination) .

The patent application by General Mills (WO 2004/008867) describes the direct injection of chocolate into a very cold yoghurt (0 to 5°C, preferably 0 to 3°C) in order to allow "spontaneous" fragmentation of the chocolate into pieces in the yoghurt, without requiring any subsequent cutting/milling of the chocolate. However, the method described requires investing in a complete production line for each yoghurt metering device in each factory. In addition, any interruption in the production of chocolate/injection stops the production of the milk product containing chocolate pieces. Finally, there is no time to validate the microbiology of the chocolate before it is used in production and introduced into the milk base

(risk of having to discard a large amount of finished product in the event of a contamination) . In addition, the chocolate used in this method has a fat content of 24 to 45% by weight, which does not make it possible to maintain the crunchiness throughout the conservation of the product .

This is because maintaining the crunchiness requires the use of chocolate with a higher fat content (typically > 65% by weight of fat for a dark chocolate, preferably approximately 75% by weight of fat) . This increase in fat content is necessary for this aim of obtaining a crunchier texture, despite the new technical difficulties that it engenders. A chocolate with a higher fat content, which is much more fluid in the molten state, means that:

there are risks of sedimentation of the solid particles (sugar, cocoa, etc.) in suspension in the chocolate (as long as this chocolate is not crystallized) , hence a heterogeneous formula and risks of blocking; - there is a risk of the chocolate mixing with the yoghurt before the former has crystallized (giving a brown yoghurt) ; there is a greater need for refrigeration: in order to absorb the latent heat from crystallization of a chocolate containing 75% by weight of fat, 2.3 times more refrigeration is needed than for a chocolate containing 32% by weight of fat.

The device described in the General Mills patent would not make it possible to use such fatty chocolates: firstly, there would, with the injection device indicated (perpendicular to the powerful flow of yoghurt in order to break up the chocolate) , be a risk of the chocolate mixing with the yoghurt before it had crystallized (giving a brown yoghurt) ; in addition, the additional need for refrigeration in order to crystallize the chocolate with a higher fat content would not longer allow the solidification and instantaneous fragmentation described.

Patent WO 00/07456 describes a method for sterilizing chocolate or a chocolate-like product that makes it possible to minimize the organoleptic damage thereto. This chocolate or chocolate-like product can then be used in fresh milk products in the form of chips. However, that patent does not describe the method for preparing a fresh milk product containing chocolate chips or chips of a chocolate-like product, nor the possibility of using a sweetened aqueous preparation containing said chips . Moreover, nothing is indicated regarding the way in which the chocolate or the chocolate-like product is kept crunchy, nor how to conserve the sterilized state without recontamination until the final metering into the pot.

Surprisingly, the inventors of the present application have discovered that it is possible to obtain acidic (advantageously having a pH of between 3.0 and 4.8) or neutral (advantageously having a pH of between 4.8 and 7.3, advantageously between 5.5 and 6.8) fresh milk products containing pieces of pasteurized or sterilized chocolate or chocolate-like product, and having a shelf life of between 12 days and 6 weeks at a temperature of between 1 and 1O⁰C, by implementing a method using sweetened aqueous preparations containing said chocolate pieces. This method prevents recontamination at all stages until consumption, and is less expensive (in terms of investment and operating costs) , more flexible and more productive than those proposed in the state of the art. Moreover, the chocolate pieces keep their crunchiness throughout the shelf life of the milk product, without requiring the use of preserving agents or dual compartments. In the case of final use of the sweetened aqueous preparation containing the chocolate pieces in an acidic fresh milk product (fermented or acidification via ingredients) , it is sufficient to pasteurize the chocolate (before fermentation or acidification of the milk) and the sweetened aqueous preparation (no need to sterilize, since the sporulated bacteria do not grow at pH < 4.8/0 to 10°C/30 days) . It is also possible, less advantageously, to use a chocolate or a sweetened aqueous preparation that is sterile. In fact, the advantages of simple pasteurization compared with sterilization are as follows:

1. It is much easier to pasteurize chocolate than to sterilize it. 2. It is possible to pasteurize the piping dry, with chocolate in certain cases (whereas, in the sterile version, in-place cleaning, sterilizing with hot water or with steam, and then drying must be carried out) . 3. There is better control of recontamination. In addition, in the event of accidental contamination, there is no substantial pathogenic risk (essentially the appearance of a modifying flora) .

For use of the sweetened aqueous preparation containing the chocolate pieces in a neutral fresh milk product, the chocolate and the sweetened aqueous preparation must be sterilized. A chocolate or an aqueous preparation that have only been pasteurized cannot be used.

In addition, the method discovered does not necessitate investing in a complete production line for each fresh milk product-metering device in each factory. In addition, any interruption in the production of the pasteurized or sterilized chocolate/injection does not stop the production of the milk product containing chocolate pieces. Finally, there is time to validate the microbiology of the sweetened preparation before it is used in production and introduced into the milk base (no risk of having to discard a large amount of finished product in the event of contamination) .

In addition, the method of production, according to the present invention, by injection of the pasteurized or sterilized chocolate in the liquid state into a sweetened aqueous preparation and crystallization by taking advantage of the coldness of the sweetened aqueous preparation makes it possible, while ensuring the microbiological control of the ingredients, to overcome the following obstacles: preventing the chocolate from mixing with the sweetened aqueous preparation, which would reduce the water resistance (maintaining of the crunchiness of the chocolate) , or would even turn the sweetened aqueous preparation brown; preventing hydration of the chocolate in the sweetened aqueous preparation, which would add to the future hydration in the fresh milk product (the total lifetime in contact with an aqueous product is approximately doubled) . It should be noted that the chocolate formulations used are only a water barrier if the fat is sufficiently crystallized. When the solid fat content (SFC) is too low, the water in the sweetened aqueous preparation rapidly penetrates into the chocolate, which reduces its crunchiness; controlling the size of the chocolate pieces, which prevents blocking of the downstream installations. The method must therefore comprise a step consisting in cutting the chocolate, but this step must minimize the loss of texture of the sweetened aqueous preparation, which would result in the need to add texturing agents (new ones or in greater amount) ; preventing the demixing of the chocolate pieces in the sweetened aqueous preparation, by controlling the viscosity or gel strength of the sweetened aqueous preparation.

The present invention therefore relates to a method for producing a sweetened aqueous preparation in which 8 to 30% by weight, advantageously 10 to 30% by weight, advantageously 10 to 20% by weight, relative to the total weight of the preparation, of chocolate pieces are dispersed, which method comprises the following successive steps :

a) pasteurization of the chocolate having a fat content of between 43 and 85% by weight with a pasteurization strength Fz of between 6000 and 10 000 000 min, advantageously between 10 000 and 500 000 min, even more advantageously between 15 000 and 100 000 min,

or sterilization of the chocolate having a fat content of between 43 and 85% by weight;

b) cooling of the pasteurized or sterilized chocolate to a temperature of between 24 and 45°C, advantageously between 24 and 38°C;

c) injection of the pasteurized or sterilized, cooled chocolate into a stream of pasteurized or sterilized, sweetened aqueous preparation having a temperature of between the freezing point of the sweetened aqueous preparation and 15°C, advantageously between the freezing point of the sweetened aqueous preparation and 10⁰C;

d) solidification of the pasteurized or sterilized chocolate injected;

e) optional cutting and mixing of the injected and solidified, pasteurized or sterilized chocolate in the pasteurized or sterilized, sweetened aqueous preparation;

f) recovery of a sweetened aqueous preparation in which 8 to 30% by weight, advantageously 10 to 30% by weight, advantageously 10 to 20% by weight, relative to the total weight of the preparation, of chocolate pieces having a fat content of between 43 and 85% by weight are dispersed, said preparation being conserved at a temperature of less than 10⁰C for at least 3 weeks, advantageously at least 6 weeks.

For the purpose of the present invention, the term "sweetened aqueous preparation" is intended to mean any sweetened aqueous preparation with a 25 to 60% water content (without the chocolate pieces) , which may or may not be flavored, and which is intended to be used in acidic or neutral fresh milk products. According to the present invention, this preparation is not based on milk. This preparation may contain monosaccharides and disaccharides, glucose syrups or fructose syrups, starch syrups with a D.E. of 21 to 100, soluble fiber, polyols, strong sweeteners (i.e. sweeteners which have a sweetening power several hundred times greater than that of sucrose, such as, for example, aspartame, potassium acesulfame or saccharin) , texturing agents, dyes, flavorings, fiber, cocoa, fruits, etc. Advantageously, the Aw measured at 25°C will be < 0.96, advantageously < 0.95, and even more advantageously < 0.93. Advantageously, the pH of the preparation is neutral (advantageously between 4.8 and 7.3) or acidic (advantageously between 3.0 and 4.8) . The acidification is obtained with one or more food acids, advantageously with lactic acid, citric acid or phosphoric acid. The texture of the sweetened aqueous preparation will have to be sufficiently gelled to prevent settling out of the chocolate pieces due to gravity/Archimedes pressure, for at least 3 weeks. For this reason, the sweetened aqueous preparation will necessarily comprise a gel-forming agent, for example of the pectin or gel-forming carragheenans type, advantageously at a dose < 1.5%, preferably of between 0.15 and 0.7%. These gel-forming agents will be used in the presence of a dose of calcium suitable to be functionalized, as known to those skilled in the art. Advantageously, this gel-forming agent will be combined with one or two thickeners : a modified starch such as acetylated distarch adipate (advantageously < 5%, advantageously between 1 and 4%) ; - another thickener: either xanthan gum (advantageously < 0.15%, advantageously between 0.01 and 0.08%), or another thickener chosen from the group consisting of guar flour, carob flour or caragheenans (advantageously between 0.05 and 0.8%, advantageously at 0.2%) .

The dose of thickener and of gel-forming agent used will be adjusted by those skilled in the art, in particular so as to take into account the water content and the thickening effect of the other ingredients (in particular, glucose-fructose syrup or starch syrup or soluble fiber) .

The rheological behavior of the sweetened aqueous preparation is evaluated using a viscoelastometer (Physica MCR300, Anton Paar) . This equipment makes it possible to evaluate the viscoelastic behavior of a material, i.e. to quantify the respective contributions of solid type (in the form of the elastic modulus G') and of liquid type (in the form of the viscous modulus G") , under given temperature, frequency or strain conditions. The protocol used is as follows: the sample is placed in a measuring cylinder. The moving part for measurement is a layout of 6-vane shear device type, especially designed to measure the rheology of fragile fluids (such as those which are thixotropic : gelled, etc.) and/or fluids containing pieces. After the measuring layout has been lowered into the preparation and a waiting time of 15 minutes has elapsed in order to ensure that the temperature has come to 1O⁰C (maximum storage temperature of the finished product) , two rheological tests are carried out successively:

1. a frequency scan from 100 to 0.01 Hz, using a low strain (0.1%) in order to be in the linear viscoelastic region,

2. a strain scan, at a fixed frequency of 1 Hz and over a strain range of 0.01% to 100%.

The measurement is carried out directly on the sweetened aqueous preparation containing the chocolate pieces, stored beforehand for at least 36 hours at 10⁰C. The results are generally as follows:

1. the frequency scan shows an elastic modulus that dominates the viscous modulus over the entire frequency range examined: this indicates that, at the low strains used, the material behaves essentially as a solid. This behavior is linked to the existence of a three-dimensional gel network created by weak interactions between chains of texturing agents (elastic modulus typically between 10²

(10 to the power of 2) and 10⁴ Pa) . This resting "solid" behavior prevents migration of the chocolate pieces in the preparation during storage in containers;

2. in the second test, the strain is gradually increased, which leads to a decrease, which is first gradual and then more marked, in the viscoelastic moduli. Thus, in an example according to the invention, for strains > 50%, the elastic modulus becomes less than the viscous modulus, which indicates that the material behaves, overall, as a liquid. The gradual increase in strain produced in this test therefore causes weakening and then rupture of the gel network. This is what will allow the material to flow like a viscous liquid, and to be withdrawn by pumping before use in the final milk product.

For the purpose of the present invention, the term

"chocolate" is intended to mean chocolate and chocolate- like products.

For the purpose of the present invention, the term

"chocolate-like product" is intended to mean any confectionery fatty mass, with a water content < 4% by weight (before being brought into contact with an aqueous product) , containing a continuous fatty phase consisting of one or more fats of vegetable or animal origin and whose properties are similar to those of cocoa butter (crunchy texture) . These fatty masses are generally called coating chocolate or compound.

This chocolate or this chocolate-like product can be flavored with caramel, with coffee, with mint, etc., as a supplement or as a substitution for the cocoa.

In an advantageous embodiment of the invention, the chocolate comprises between 65 and 78% by weight of fat, advantageously between 68 and 78% by weight of fat, advantageously between 74% and 76% by weight of fat, relative to the total weight of the chocolate. In general, the fat is cocoa butter. It is, however, possible to replace up to 20% by weight of the cocoa butter with anhydrous milk fat (AMF) or to replace all or some of the cocoa butter with one or more vegetable fats having an SFC at 10⁰C (solid fat content) of greater than 50% by weight. In the case of the chocolate-like products, the fat can also be solely a fat of vegetable origin, in particular lauric fats: for example, hydrogenated fractionated palm kernel oil (sold by Fuji Oil Europe) . These lauric fats should not be combined with cocoa butter for reasons of crystallization (eutectic) incompatibility. The cocoa butter contained in cocoa powder (10-12% fat) is, however, tolerated, but care will be taken to maintain the cocoa butter/total fat ratio at preferably < 5%, so as to maximize the crunchiness.

Very high fat chocolates are unstable: there is rapid sedimentation due to the low viscosity, hence a heterogeneity in the recipe, and therefore a heterogeneity in the taste and in the water resistance. Preferably, the chocolate purchased will have a low fat content, so as to have a viscosity > 0.5 Pa.s at 4O⁰C (according to the

"Casson" method, OICC No. 10 (1973)) , and the remainder of the fat content will be adjusted at the site of pasteurization. This prevents settling out in transport tankers that do not have stirring, for example.

In an advantageous embodiment of the invention, the chocolate has a sugar concentration of greater than 5% by weight, advantageously greater than 10% by weight, even more advantageously greater than 11% by weight, relative to the total weight of the chocolate. Advantageously, this sugar content is approximately 14% by weight, relative to the total weight of the chocolate. The sugars are in particular monosaccharides and disaccharides. Among monosaccharides, mention may be made of fructose, galactose or glucose. Among disaccharides, mention may in particular be made of sucrose, which is the sugar commonly used for producing chocolate, but the sucrose can be partially or completely replaced with another disaccharide, such as lactose, for example in an amount of 0 to 50% by weight, or with polyols which, at the jacket temperature during the pasteurization or sterilization step, do not melt and do not release crystallization water. These are, for example, mannitol and maltitol . The preferred variant is, however, sucrose.

The sweetened aqueous preparation containing chocolate pieces according to the present invention is intended to be incorporated into an acidic or neutral fresh milk product .

In order for the chocolate to keep its crunchiness, it is advantageous to choose its composition according to the local free water of the fresh milk product, obtained after incorporation of the sweetened aqueous preparation (referred to below as final fresh milk product) , and without taking into account the local free water of the chocolate pieces present in the sweetened aqueous preparation. In the final fresh milk product, this sweetened aqueous preparation will be mixed with an intermediate fresh milk product, that has a local free water content greater than that of the sweetened aqueous preparation.

Thus, in a particular embodiment of the invention, the chocolate has a parameter (τ) less than 3, advantageously less than 2, advantageously less than 1, the parameter (τ) being defined by the following equation (1) : τ= (-[water] + 0.37) x F + (5.25 x [water] - 1.67) x (S+SMP) + (26.2 x [water] - 9.6) x C + (61 x [water] - 14.5) x (S+SMP) x C, with: - [water] is the local free water content of the final fresh milk product (in g/g) , F is the fat content of the chocolate (in g/g) , - S + SMP is the content of sugars + skimmed milk powder of the chocolate (g/g) ,

C is the content of dry and defatted cocoa of the chocolate (in g/g) .

The local free water content [local free water] is defined by the following equation (2) :

[local free water] = [total water] xA_{w 2}5_°c/ (100-FM) in which:

[local free water] is given in grams of water per gram of the final fresh milk product (excluding chocolate pieces) ;

FM is the fat of the final fresh milk product, expressed in grams of fat per 100 grams of the final fresh milk product (excluding chocolate pieces) ;

[total water] is given in grams of water per 100 grams of the final fresh milk product (excluding chocolate pieces) .

For example, for a non-fat final fresh milk product containing 77% of water and having an A_{w 25}°c of 0.96, the local free water content is 73.9%.

A sweetened aqueous preparation has a local free water content of between 27 and 60%.

For an application with a small thickness of chocolate (< 3 mm) , it is necessary that τ < 2. The thinner the thickness of the chocolate, the lower τ must be in order for the chocolate to keep its crunchiness .

Thus, according to the desired thickness of the chocolate pieces, the value of τ must not exceed a limiting value in order to ensure water resistance and therefore a crunchiness that is sufficient. The greater the thickness, the higher the limiting value of τ may be. For this reason, those skilled in the art will be in a position to choose the optimal composition of the chocolate according to the desired thickness. Similarly, the value of τ will have to be chosen according to the duration of conservation and the temperature of conservation of the sweetened aqueous preparation containing the chocolate pieces. The shorter the duration or the lower the temperature, the higher this value may be. In general, τ is advantageously less than 2, preferably less than 1.6.

The composition of the chocolate having the appropriate characteristics in the context of the present invention is therefore defined in particular by means of a test described in the form of a mathematical equation which means that those skilled in the art do not have to carry out experiments. However, where required, an experimental procedure that allows those skilled in the art to determine the chocolate compositions which satisfy the aims that the invention proposes to achieve is indicated below. '

For example, the test which consists in bringing slices of chocolate 1.5 + 0.2 mm thick and 20 mm in diameter into contact with an agar gel having a determined local free water content of 74% is carried out. The chocolate slices are obtained after tempering and cooling of the chocolate to 13°C, and storage for 2 days at 20⁰C and then for 12 hours at 10⁰C. The gel is poured into syringes which are cut at their end and then covered with the slice of chocolate and are then closed again with a stopper. The whole is stored for 35 days at 1O⁰C and the water uptake of the slice of chocolate is measured at D35 by the "Karl Fischer" method, OICC No. 105 (1988) .

The compositions which satisfy the criteria of the invention are those whose percentage water uptake after 35 days of storage at 1O⁰C will be < 17.7%; table 1 below gives an indication of the percentages of water uptake after 35 days at 1O⁰C as a function of the water resistance of the chocolate.

Table 1: Percentages of water uptake in g/100 g after 35 days at 10°C as a function of the water resistance of the chocolate

A gel composition having a local free water content of approximately 74% is given below in table 2.

Table 2: % composition, by weight, of gel having a local free water content of approximately 74%

The chocolate used in the context of the present invention may be dark chocolate, milk chocolate or white chocolate.

In the case of milk chocolate or white chocolate, some or all of the dry and defatted cocoa is replaced with skimmed or non-skimmed powdered milk. Advantageously, the composition of the chocolate according to the present invention is such that the C/ (S+SMP) ratio is < 2.3, advantageously less than 1.6, even more advantageously less than 1 (C = content of dried defatted cocoa of the chocolate (in g/g) , S+SMP = content of sugar + skimmed milk powder of the chocolate (in g/g) ) .

Moreover, in the case of the use of other milk powder derivatives (lactoserum, buttermilk, permeate, lactoprotein, etc.) , their non-fat component will be counted as "SMP" . Polyols or other filling sweeteners can be substituted for the sugar and are then counted as sugars (S) in the above formulae.

All the water-resistant chocolate formulae described in patent application WO 00/70960 can be used in the context of the present invention.

Advantageously, the chocolate used in the context of the present invention corresponds to the formulae indicated in table 3 below:

Table 3: % composition, by- weight, of the chocolate formulae

In these formulae: - the cocoa mass contains, as % by weight: 1.7% water,

53.4% fat and 44.95% dry defatted cocoa,- its water content is < 1%, the particle size thereof is advantageously fine

(minimum 90% of particles < 20 μm; maximum 0.2% of particles > 75 μm) and the contamination thereof is advantageously < 1000 cfu/g; the dark chocolate contains, as % by weight: 0.5% water, 27.7% fat (approximately 0.3% of which is lecithin) , 22.3% dry defatted cocoa and 49.5% sugar; advantageously, the particle size thereof measured with a Palmer is < 30 μm, and the contamination thereof is advantageously < 1000 cfu/g; the cocoa powder containing 11% fat contains, as % by weight: 4% water, 11% fat and 85% dry defatted cocoa.

Advantageously, these three constituents, along with the cocoa butter, are sold by the company Barry-Callebaut. Advantageously, the chocolate-like product used in the context of the present invention corresponds to the formulae indicated in table 4 below:

Table 4: % composition, by weight, of the chocolate-like product formulae

The composition of the recipes of the lauric chocolate- like products is given in table 5 below. Advantageously, the particle size thereof measured with a Palmer is

< 30 μm, and the contamination thereof is advantageously

< 1000 cfu/g. Table 5: % composition, by weight, of the recipes of the lauric dark chocolate-like products

The hydrogenated and fractionated vegetable fat used in tables 4 and 5 is hydrogenated palm kernel stearin (i.e. hydrogenated and fractionated) . Two advantageous examples are available from Fuji Oil Europe (ref: Palkena H50 -G or HB7 G) . In particular the solid fat content of these two plant fats is given in table 6 below.

Table 6: Solid fat content (SFC) as a proportion of solid fat/total fat (as %) at a given temperature

HPKS Palkena, HPKS Palkena,

Cocoa butter Ref H50 G Ref HB7 G

SFC at 10 °C 84.3

SFC at 15 ⁰C 78.4

SFC at 20 ⁰C 71 > 91 > 90

SFC at 25 ⁰C 62.6 82-91 73-83

SFC at 30 ⁰C 37.9 38-47 26-35

SFC at 35 ⁰C 0.8 < 5 < 5

SFC at 40 ⁰C 0 In a particular embodiment of the invention, the method according to the present invention comprises a step (α) , prior to step (a) , consisting of preparation of the chocolate, advantageously by mixing the fat and the chocolate, and optionally the cocoa mass and/or the cocoa powder. Advantageously, the ingredients used are cocoa mass, dark chocolate, cocoa powder containing 11% by weight of fat and cocoa butter in the case of chocolate, and the lauric dark chocolate-like product, hydrogenated and fractionated vegetable fat and cocoa powder 10-12 in the case of the chocolate-like product. Advantageously, the proportions used are those indicated in tables 3 to 5 for formulae 1 to 4 and recepies 1 and 2.

In a particular embodiment of the invention, the chocolate, prepared on site in step (α) or purchased, is deaerated under vacuum before it is used in the method according to the present invention (i.e. before step (a) of the method) . Such a deaeration can make it possible to obtain a better effectiveness of the thermal treatment and a better water resistance (more compact chocolate) .

Step (a) of the method according to the present invention therefore consists of pasteurization or sterilization of the chocolate.

In a first variant, the chocolate is therefore pasteurized with a pasteurization strength Fz of between 6000 and 10 000 000 min, advantageously between 10 000 and 500 000 min, even more advantageously between 15 000 and 100 000 min. In this case, step (B) of the method according to the present invention consists of the injection of the sweetened aqueous preparation containing the chocolate pieces into an acidic milk base.

Surprisingly, for a dark chocolate, no organoleptic degradation occurs with these scales.

In 1997, PCSA (Danone Group) modeled the thermo-resistance of A. niger spores in artificial contamination in chocolate (< 1% of water) : • Decimal reduction time D (time necessary to reduce by 90%, i.e. to divide by 10, a population of a given mircoorganism at a given temperature) at 70⁰C: D₇₀o_C = 2000 min; 2000 min at 70⁰C (reference temperature) are therefore required to destroy the population of A. niger by 90%.

• Z (increase in temperature in ⁰C which makes it possible to divide D by 10) = 7.65°C; it is therefore necessary to raise the temperature by 7.65⁰C in order to reduce D 10-fold (therefore

D₇₇.65°c = 200) .

A. niger is one of the most thermoresistant micro¬ organisms of those that must be destroyed during pasteurization. These data are used to calculate the pasteurization strength Fz according to formula (3) below: Fz = time x io^(T-^7O)/2 Pasteurization time at T in min Fz: pasteurization strength in min T: pasteurization temperature in ⁰C

In reality, since the temperature is not constant during the thermal treatment, Fz is calculated by time x temperature integration, as is conventionally done in the food preservation industry (appertization) .

The effectiveness of pasteurization is then calculated: EP = Fz/D_70°c_/ which measures the logarithmic decrease in the population for the given thermal treatment.

For example, Fz = 6000 min can correspond to a thermal treatment of 6000 min at 70⁰C or 0.72 min at 100⁰C or 1 min at 98.9°C. These treatments reduce the population of A. niger 1000-fold (3 Log) Fz = 10 000 000 min can correspond to a thermal treatment of 13.1 min at 115°C.

A little water, preferably in the form of steam, can be injected in order to pasteurize the chocolate during step

(a) . It may be, for example, a proportion of 0.5 to 1% by weight relative to the total weight of the chocolate. This can make it possible to improve the pasteurization if the starting materials are very contaminated: it is not then necessary to evaporate the water introduced, given the small amounts used.

In an advantageous embodiment, the pasteurization step (a) is carried out dry. Advantageously, this step (a) is carried out by heating, optionally under pressure.

Advantageously, this step (a) comprises the following successive steps:

1. Heating, advantageously using a device equipped with a double-walled jacket, to a temperature > 74⁰C, advantageously to a temperature of between 90 and 12O⁰C, advantageously to a temperature of approximately 100°C+/-5°C so as to obtain Fz > 6000 min,

2. Cooling to a temperature < 75°C, advantageously using a device equipped with a double-walled jacket.

During the heating in the pasteurization step (a) , a little water evaporates into the "overhead of the tank" and it is advantageous (but not strictly necessary) to remove it, in order to increase the water resistance of the chocolate and to limit sugar aggregates. In particular, two solutions can be envisioned for removing this water:

1. If the heating is carried out at atmospheric pressure: the gases and the steam can exit via a sterile filter (or sintered glass) ;

2. If the heating^' is carried out under pressure using a device equipped with a closed pasteurization tank, the steam can be degassed just after the end of pasteurization (before cooling) by being placed in the open air and/or by being placed under vacuum.

Option 2 gives a slightly greater effectiveness of pasteurization of the chocolate, but may cause some sugar aggregates in the pasteurized chocolate.

In an advantageous embodiment, the chocolate is pasteurized during step (a) by means of a batch method, advantageously in a device equipped with a pasteurization tank that has a double-walled jacket, advantageously equipped with a stirrer that scrapes the walls.

Advantageously, the heating fluid in the double-walled jacket is hot water (optionally overheated for temperatures > 100⁰C) , steam (in particular for pasteurization temperatures > 100⁰C) or any other heat- transfer fluid (oil, for example) .

Steam allows shorter pasteurization cycle times, since the heating is more rapid than a loop of hot water. Advantageously, the steam pressure in the double-walled jackets will be < 150 KPa in absolute pressure, so as to limit the wall temperature to a temperature < 111°C.

Advantageously, step (a) of the method can be carried out : batchwise; the pasteurization tank can thus serve as a buffer tank before the metering device/use (for a continuous production, 2 tanks are required, in parallel) . Advantageously, the tank and the piping of the device implementing the method according to the present invention are pasteurized at the same time as the chocolate;

- continuously, the device used for the pasteurization comprising no pasteurization tank, but a heat exchanger, for example with a scraped surface (with an installation devoted to pasteurization, there is never any need for cleaning: it is sufficient to pasteurize the downstream piping with chocolate according to the scale above, and to send the chocolate insufficiently pasteurized into the starting tank so as to recycle it) .

Advantageously, this step (a) makes it possible to obtain a pasteurized chocolate comprising a contamination of less than 1 cfu/g of bacteria, yeast and mold, excluding bacterial spores, which cannot germinate at a temperature of less than or equal to 10⁰C, advantageously less than 1 cfu/100 g, advantageously less than 1 cfu/kg (1 cfu/g = 1000 cfu/kg) .

Advantageously, the same tank is used for implementing steps (a) and (α) .

In a particular embodiment of the invention, the method according to the present invention comprises an intermediate step (al) , between steps (a) and (b) , consisting of storage with stirring of the pasteurized chocolate at a temperature of between 28 and 75°C, advantageously between 65 and 75⁰C, optionally without overpressure.

Once pasteurized (step (a) ) , the chocolate can be stored under pressure (step (al) ) , advantageously at a temperature of between 28 and 50⁰C, advantageously between 10 and 30 KPa. When the storage temperature is < 36°C, the lower the temperature, the shorter the storage time will have to be (risk of solidification) . For example, for formula 1 indicated in table 3, storage at 33⁰C can be carried out for approximately 40 hours without too marked an increase in viscosity (its viscosity at 33°C is of the order of 0.26 Pa. s under a strain of 150 Pa) .

In a variant of the method according to the present invention, the storage is carried out under pressure at a temperature of between 28 and 38⁰C, preferably between 30 and 34⁰C.

In another variant of the method according to the present invention, the storage is carried out under pressure at a temperature of between 38 and 50⁰C, advantageously at a temperature of 45⁰C.

In another variant of the method according to the present invention, the storage is carried out at a temperature of between 65 and 75⁰C without overpressure, i.e. at atmospheric pressure.

Whatever the variant, the chocolates, which are very fluid, must be permanently stirred, in order to prevent settling out of the solid particles in suspension and fat separation.

In the method according to the present invention, step (al) is carried out in a device equipped with an intermediate buffer tank. However, advantageously, the chocolate is stored in the pasteurization tank of step (a) . Thus, the same tank is used for steps (a) and (al) .

Even more advantageously, the same tank is used for steps (α) , (a) and (al) .

Moreover, it is advisable to maintain the pasteurization of the chocolate before it is injected during step (c) . If the pasteurized chocolate remains stored in the pasteurization tank during step (al) , this avoids having to pasteurize a downstream tank, and the tank is thus pasteurized at each batch at the same time as the chocolate. Since the chocolate is anhydrous, it is not necessary to clean between two batches, unless the flavors or colors of the chocolate are incompatible. No time is therefore lost due to cleaning/pasteurization of the tank. In order to prevent any recontamination, the tank is advantageously pressurized by a sterile gas source (typically, 10 to 30 KPa) .

Since the chocolate is incompatible with water, all the pipework downstream of the injection step (c) , in the device for implementing the method according to the present invention, is advantageously pasteurized dry, in particular at the same time as the pasteurization of the chocolate at each batch, advantageously with a device having a double-walled jacket at 100°C/10 to 20 min, after cleaning or without cleaning. Other dry sterilization techniques exist, for example with hot fat (100°C/l0 min) .

Alternatively, the pipework downstream of the injection step (c) , in the device for implementing the method according to the present invention, can also be pasteurized conventionally by cleaning in place, and then pasteurization with hot water or steam: however, it is necessary to drain off the water and preferably dry the installation before sending the pasteurized chocolate thereto (sterile gas stream, or vacuum, heated by double- walled jackets, for example filled with steam at 110 KPa in absolute pressure) .

If step (al) is carried out in a device equipped with an intermediate buffer tank, i.e. steps (al) and (a) are not carried out in the same tank, the following two cases exist : - the storage (step (al) ) is carried out at a temperature of less than 60-65⁰C. The intermediate buffer tank will then have to be pasteurized during the 1st use and each time the pasteurized state is lost (since the chocolate is virtually anhydrous, no microbial development can take place, except in an exceptional case: maintenance, etc.) . This may be carried out conventionally

(cleaning, then hot water sanitization, then evaporation) , or preferably by heating ensuring a pasteurization strength Fz > 6000 min (for example, 22 h at 75⁰C) , preferably Fz > 20 000 min; the storage (step (al) ) is carried out at a temperature > 75⁰C so as to have "continuous" pasteurization.

The above steps (a) and (al) should avoid the incorporation of air, which reduces the water resistance of the chocolate. Optionally, degassing (for example, by placing the pasteurization and/or batch storage tank under vacuum) can be carried out .

In a second variant, the chocolate is sterilized. Advantageously, the method described in patent application WO 00/07456 is used. Thus, advantageously, the water activity (Aw) of the chocolate is increased to a value greater than approximately 0.7, advantageously greater than 0.8, the hydrated chocolate is subjected to a heat sterilization step, and the water is eliminated so as to recover an essentially sterile chocolate, which exhibits a contamination, in particular with respect to sporulated bacteria, that is at least 1000-fold less (3 log) than the starting chocolate, in particular less than 1 CFU/g.

Advantageously, the water activity is increased to a value of greater than 0.87, in particular between 0.9 and 0.96.

Advantageously, this method is carried out batchwise in the same tank.

According to the Aw, and the temperature and the duration of the heat treatment, the invention makes it possible in particular to obtain a reduction in microorganisms, of between 3 and 12 log (1000 to 10¹² times less) , in particular between 3 and 9 log, and advantageously of at least 5 log with respect to sporulated bacteria, advantageously of at least 6 log. Taking into account the initial contamination of the ingredients (100 to 10 000 sporulated bacteria per gram, approximately) , this makes it possible to obtain an "essentially sterile" chocolate containing less than 1 CFU/g, preferably less than 1 CFU/lOO g, and preferably less than 1 CFU/kg.

The water activity of a product is a notion that is well known in the food sector, this parameter, abbreviated to Aw, measures the water availability in a sample. In most cases, this water activity is not proportional to the water content of the product.

Methods for measuring the Aw of a product are known to those skilled in the art. The Aw is generally measured at 25°C.

This sterilization method is particularly suitable for the treatment of dark chocolate. However, this method is also suitable for the production of various types of milk chocolate or white chocolate, that are essentially sterile. It is, for example, known that white chocolate contains no dry and defatted cocoa.

To hydrate the chocolate in order to attain the target Aw for sterilization, the required water is added either entirely at the start, or partly at the start and partly during the heating to the sterilization temperature for the chocolate, or only during the heating. This addition of water during the heating will advantageously be carried out by direct injection of food-quality steam into the chocolate.

The water can be added in pure form, or via aqueous compounds, for instance milk (skimmed or non-skimmed, concentrated or non-concentrated) , cream or other milk derivatives, fruit juices, etc.

The Aw is measured in the following way and is referred to as equivalent Aw:

The proportion of water corresponding to the total water content that will be added at the end of the sterilization step (added water + condensed steam) is added to the chocolate, in a suitable laboratory mixer. Stirring is carried out for 15 min at 50⁰C, avoiding any evaporation, and the mixture is left to stand at 20⁰C in a closed flask containing little head space. After 24 hours, the chocolate is reduced to fine powder or is mixed (according to its consistency) and its Aw is measured at 25°C on a conventional device of Aqualab CX-2 or Decagon type.

In the context of the present invention, step (b) of the method consists in cooling the pasteurized or sterilized chocolate to a temperature of between 24 and 45⁰C, advantageously between 24 and 38⁰C.

In a particular embodiment of the invention, step (b) consists in tempering and cooling the chocolate to a temperature of between 24 and 30⁰C. Advantageously, if the chocolate is not tempered, it is cooled to a temperature of between 30 and 45⁰C, advantageously between 30 and 4O⁰C.

The tempering of the chocolate (presolidification) is not obligatory in fresh products, i.e. in the method according to the present invention, as it is for conventional applications stored at ambient temperature. However, it accelerates the solidification of the chocolate and slightly improves its crunchiness . The tempering may be carried out by means well known to those skilled in the art in the chocolate making industry. It may thus be very simplified, since, although in the chocolate making industry only V-shaped (stable) chocolate crystals are selected, chocolate crystals of any shape can be accepted here, since the storage conditions according to the present invention will prevent any whitening. The essential aim of the tempering is therefore simply to accelerate the solidification of the chocolate on contact with the sweetened aqueous preparation during step (d) of the method according to the present invention, in particular by starting from a lower chocolate temperature and by having already crystallized part of the fat of the chocolate.

Advantageously, step (b) is carried out either directly in the storage tank of the optional step (al) , or on line, advantageously using a device equipped with a heat exchanger (for example, a scraped-surface exchanger) . The on-line scraped-surface exchanger allows the chocolate to be cooled to a lower temperature, since the chocolate does not remain at this temperature for very long and will not have the time to solidify.

In the context of the present invention, step (c) of the method according to the present invention consists of the injection of the pasteurized or sterilized, cooled chocolate into a stream of pasteurized or sterilized, sweetened aqueous preparation having a temperature between the freezing point of the sweetened aqueous preparation and 15°C, advantageously between the freezing point of the sweetened aqueous preparation and 10⁰C.

The sweetened aqueous preparation according to the invention is pasteurized or sterilized by methods well known to those skilled in the art. Given the fact that chocolate melts above 40⁰C, it is necessary to pasteurize or sterilize the sweetened aqueous preparation separately, without the chocolate pieces, and then to introduce and solidify the chocolate in this preparation. The preparation should subsequently never be taken to more than 25⁰C, advantageously not to more than 20⁰C, so as not to melt the chocolate, or simply degrade its water resistance.

In a particular embodiment of the invention (variant 1) , step (c) is carried out by continuous injection of the chocolate in the form of strips into the sweetened aqueous preparation. In this case, step (e) consists of the injected and solidified, pasteurized or sterilized chocolate being cut into pieces and mixed into the pasteurized or sterilized, sweetened aqueous preparation, by means of a dynamic mill, and the longest dimension of the chocolate pieces obtained in step (e) is advantageously between 1 and 6 mm, advantageously between 4 and 6 mm. Advantageously, in this case, the solidification time in step (d) is between 30 and 600 s. The injection of the chocolate into the sweetened aqueous preparation according to variant 1 of step (c) of the method according to the present invention is therefore carried out in a continuous stream. The chocolate is therefore advantageously injected in the form of "strips" of varied cross section (round, rectangular, cross-shaped, etc . ) .

Advantageously, the injecting device used deposits the stream of chocolate in the middle of the stream of sweetened aqueous preparation. Advantageously, the stream of sweetened aqueous preparation is parallel to the stream of injected chocolate. Advantageously, the linear speed of the stream of chocolate on leaving the injecting device is equal, to within ± 40%, to that of the stream of sweetened aqueous preparation.

In a particular embodiment of the invention, step (c) is carried out by injection of the chocolate into the middle of the stream of the sweetened aqueous preparation, the stream of chocolate being parallel to the stream of sweetened aqueous preparation and the linear speed of the stream of chocolate on leaving the injecting device being equal, to within + 40%, to that of the stream of sweetened aqueous preparation.

The injection flow rate should be calculated according to the desired proportion of chocolate in the sweetened aqueous preparation.

In order to create an even vein of chocolate and to prevent any mixing, the linear speed of the chocolate should advantageously be as close as possible to that of the sweetened aqueous preparation (carrier fluid) . Advantageously, the flow between the stream of sweetened aqueous preparation and the stream of chocolate should be laminar (same speed) before and after the injection step (c) so as to prevent mixing between the non-solidified chocolate and the sweetened aqueous preparation.

Advantageously, the injection in step (c) is carried out using a device equipped with an injection nozzle.

Advantageously, the injection nozzle diameter will be such that the speed of the chocolate in the nozzle and the speed downstream are similar (to ± 40%) .

Advantageously, the injection is carried out using a multi-injector: this makes it possible to reduce the diameter (in the case of a round injecting device that makes it possible to obtain strips with a round cross section) of the chocolate strips compared to when a single injecting device is used, for the same proportion of chocolate, and therefore to accelerate the ratio of crystallization. Advantageously, the diameter of the strips with a round cross section will be between 2 and 8 mm, advantageously between 4 and 6 mm.

Advantageously, the injecting device used has a rectangular cross section and makes it possible to obtain a chocolate strip with a rectangular cross section, advantageously having a thickness of between 2 and 8 mm, even more advantageously of between 4 and 6 mm.

Advantageously, in order to prevent blocking of the injection nozzle, which is cooled by the stream of cold sweetened aqueous preparation, it will be insulated or insulating (for example made of Teflon ) or heated

(advantageously to a temperature of between 40 and 55°C, advantageously to a temperature of 5O⁰C) , advantageously using a double-walled jacket: this will not detemper the chocolate, since the time taken to pass through it is short .

Advantageously, the injecting device in step (c) is placed at the center of the tube.

Advantageously, the entry of water into the device for implementing steps (a) and (b) and optional steps (α) and

(al) will be avoided under all circumstances, using a device equipped with a nonreturn valve, just before the injecting device in step (c) .

Thus, in a particular embodiment of the invention, the method according to the invention is carried out in a device that has a nonreturn valve in order to separate the stream of chocolate obtained in step (b) from the stream of sweetened aqueous preparation.

In the context of variant 1 according to the present invention, step (d) of the method according to the present invention consists of the solidification of the continuously injected, pasteurized or sterilized chocolate.

This solidification is due to the contact of the chocolate with the sweetened aqueous preparation (having a temperature between the freezing point of the sweetened aqueous preparation and 15°C, advantageously between the freezing point of the sweetened aqueous preparation and 10⁰C) .

Advantageously, the device for implementing step (d) consists of a portion of linear pipework of equal diameter, with no pipe failures.

Advantageously, this device is equipped with a double- walled jacket so as to improve heat transfer (the water circulating in the double-walled jacket at a temperature between the "freezing temperature + 1°C" and the temperature of the sweetened aqueous preparation) . In this case, this device makes it possible to cool the "sweetened aqueous preparation + chocolate strip" combination.

In order for the chocolate to solidify, it must be cooled to less than 14°C, preferably to less than 10⁰C, preferably to less than 6°C, before step (e) of the method according to the present invention. If the chocolate is insufficiently solidified at the time of step (e) of the method according to the present invention, it will still be elastic at the center and the chocolate will, in general, be less water resistant.

Advantageously, the solidification time in step (d) is between 30 and 600 s.

Advantageously, the device for implementing step (d) of the method according to the present invention is equipped with a length of pipework that is sufficient to ensure the solidification time of the chocolate. Advantageously, this length is between 3 and 40 m. This pipework can be placed vertically in order to limit the impact of movement linked to Archimedes pressure in the event of the machine stopping.

When the industrial flow rates are too high, the pipe length or diameter required to ensure the solidification time of the chocolate may be too great. In this case, the method according to the present invention advantageously comprises an intermediate step (dl) , between steps (d) and

(e) , consisting of intermediate storage, with stirring, of the fresh milk product/"solid" (still "elastic") chocolate ribbon mixture, advantageously in a stirred buffer tank, where the crystallization continues so as to finally obtain a really hard chocolate.

In a particular embodiment of variant 1 of the invention, step (e) of the method according to the present invention consists of the pasteurized or sterilized, solidified chocolate being cut into pieces and mixing it into the pasteurized or sterilized, sweetened aqueous preparation by means of a dynamic mill.

Advantageously, the dynamic mill is chosen from the group consisting of rotary blades, propellers, centrifugal

® pumps, worms, endless screws, gear pumps, the Dosys mixer, rod boxes (rods with a square cross section) , simple rotors (cross, centrifugal pump type) with no screen or rotors/stators with screen (for example: Silverson 275) ; advantageously, in this case, the stator has large openings so as to prevent blockages .■

Advantageously, the dynamic mill provides a low rotation speed (m/s) (for example: worm + counter blade) which causes less prestructuring of the sweetened aqueous preparation. Advantageously, the dynamic mill is equipped with a counter blade.

The counter blade serves as a support and makes it possible to cut the chocolate with a lower rotation speed. The regulatable rotation speed makes it possible to adjust the size of the chocolate pieces. Advantageously, the dynamic mill is a rotor/stator with screen or a simple rotor (cross, centrifugal pump type) without screen + counter blade (the chocolate ribbon is held by the counter blade at the cutting point) . This allows better control of the maximum size of the chocolate pieces, thus making it possible to prevent blocking of the metering device downstream. In a particular embodiment of the invention, in step (c) , variant 1, a large amount of chocolate is injected in proportion to the sweetened aqueous preparation (advantageously between 50% and 95% by weight of chocolate advantageously between 65 and 90% by weight of chocolate, advantageously between 75 and 85% by weight of chocolate, the remainder consisting of the sweetened aqueous preparation) and the rest of the sweetened aqueous preparation is added in step (e) so as to obtain, during step (f) , a sweetened aqueous preparation containing the desired amount of chocolate pieces.

The advantages of this particular embodiment comprising the use of a large amount of chocolate, in particular in the versions between 75 and 90% by weight of chocolate, are:

• the proximity of the double-walled jacket, allowing good heat transfer, • the chocolate is "guided" in the tube, hence fewer risks of blocking associated with entangling of chocolate strips,

• since the chocolate strip is virtually wedged against the wall of the crystallization tube (31) , the end of the tube (31) , which opens into the cutting means, supports the strip and acts as a counter blade (34) .

Advantageously, in this variant 1, the longest dimension of the chocolate pieces obtained in step (e) is between 1 and 6 mm, advantageously between 4 and 6 mm.

In another embodiment of the invention (variant 2) , step

(c) is carried out by dropwise injection of the chocolate above the pasteurized or sterilized, sweetened aqueous preparation. In this case, step (e) consists in mixing, by stirring in general without cutting, the solidified drops of pasteurized or sterilized chocolate into the pasteurized or sterilized, sweetened aqueous preparation. Optionally, cutting can also follow this step, in particular so as to increase productivity while at the same time eliminating "doubles" (pieces stuck together) . Advantageously, the stirring in step (e) is carried out with a dynamic mixer, advantageously chosen from the group consisting of a stirred tank or a conveying device, such as a worm or an inclined plane or any other device well known to those skilled in the art. This stirring makes it possible first to prevent 2 successive injections of liquid chocolate from sticking to one another before solidification (preventing doubles or agglomerates) , and then enables homogeneous distribution of the solidified drops of chocolate.

In the context of variant 2 according to the present invention, step (d) of the method consists of the solidification of the injected drops of pasteurized or sterilized chocolate.

This solidification is due to the contact of the chocolate with the sweetened aqueous preparation (having a temperature between the freezing point of the sweetened aqueous preparation and 15°C, advantageously between the freezing point of the sweetened aqueous preparation and 1O⁰C) .

Advantageously, the device for implementing step (d) , variant 2, consists of a stirred tank. Advantageously, this device is equipped with a double-walled jacket so as to improve heat transfer (the water circulating in the double-walled jacket at a temperature between "the freezing temperature + I⁰C" and the temperature of the sweetened aqueous preparation) . In the context of the present invention, step (f) of the method according to the present invention consists of the recovery of a sweetened aqueous preparation in which 8 to 30% by weight, advantageously 10 to 30% by weight, advantageously 10 to 20% by weight, relative to the total weight of the preparation, of pieces of pasteurized or sterilized chocolate having a fat concentration of between 43 and 85% by weight, are dispersed, said preparation being conserved at a temperature of less than 10⁰C for at least 3 weeks, advantageously at least 6 weeks.

The amount of 8 to 30% by weight of chocolate in the sweetened aqueous preparation (preferably 10 to 20% by weight) is obtained in one or more passages by recirculation so as to perform a gradual enrichment

(therefore metering into a medium that is no longer a sweetened aqueous preparation, but a sweetened aqueous preparation already containing chocolate pieces : for example, 3 passages at 5% by weight produce a preparation containing 15% by weight of chocolate) .

In a particular embodiment of the invention, steps (c) to (e) are repeated at least once before step (f) , the stream of sweetened aqueous preparation containing less than 8 to 30% by weight, advantageously less than 10 to 20% by weight of chocolate obtained in step (e) being re-used in steps (c) to (e) , as pasteurized or sterilized, cooled sweetened aqueous preparation.

In another embodiment of the invention, the method according to the present invention comprises an additional step (g) consisting of storage of the sweetened aqueous preparation in which 8 to 30% by weight, advantageously 10 to 20% by weight, relative to the total weight of preparation, of chocolate pieces are dispersed, obtained in step (f) , at a temperature of between 1 and 10⁰C, advantageously between 1 and 4⁰C.

Advantageously, the storage is carried out in a tank or container, which may or may not be mobile.

The storage is carried out with or without stirring.

Advantageously, the storage time can range up to 3 weeks, advantageously up to 6 weeks.

The present invention also relates to a method for producing an acidic or neutral fresh milk product containing chocolate pieces, which method comprises the following steps:

A) production of a sweetened aqueous preparation in which 8 to 30% by weight, advantageously 10 to 30% by weight, advantageously 10 to 20% by weight, relative to the total weight of the preparation, of chocolate pieces are dispersed, by carrying out steps (a) to (f) and optional steps (α) , (al) and/or (g) according to the present invention;

(B) injection of the sweetened aqueous preparation containing chocolate pieces and having a temperature < 20⁰C, advantageously equal to 17⁰C +/- 3⁰C, in contact with a stream of acidic or neutral, pasteurized milk base having a temperature of less than 20⁰C, preferably < 15⁰C, and optional mixing of the preparation and of the milk base; (C) recovery of an acidic or neutral fresh milk product containing chocolate pieces having a fat content of between 43 and 85% by weight, said product being conserved at a temperature of between 1 and 10⁰C for a period of between 12 days and 6 weeks.

For the purpose of the present invention, the term "acidic or neutral milk base" or "acidic or neutral milk product" is intended to mean any milk product that is fermented or acidified via ingredients (advantageously, with lactic acid, citric acid or phosphoric acid) (its pH is advantageously less than 4.8, it is advantageously between 3 and 4.8) or that is neutral (its pH is advantageously between 4.8 and 7.3, advantageously between 5.5 and 6.8) . In particular, it may be a fromage frais or a fermented product containing live ferments (for example, sour cream, kefir, or the like) and in particular a yoghurt or similar fermented milk specialty products (fermented with lactic acid bacteria, such as active bifidus or L. casei) . Advantageously, it is not a mousse. Advantageously, it is a stirred yoghurt. Advantageously, the product is fermented by the addition of live ferments such as, for example, Lactobacillus bulgaricus, Streptococcus thermophilus and/or Lactobacillus acidophilus and/or bifidus.

Advantageously, the milk used in the milk base is cow's milk. However, other milks can be used as complete or partial substitution for the cow's milk, such as, for example, goat's milk, yew's milk, buffalo milk or mare's milk, or less advantageously milks of vegetable origin, such as soya milk, coconut milk or oat milk.

The pasteurized and optionally fermented, acidic or neutral milk base is obtained according to methods well known to those skilled in the art. In particular, the method for obtaining a fermented pasteurized acidic milk base comprises the following successive steps:

- homogenization of the milk base,

- pasteurization of the milk base,

- cooling of the milk base, - seeding,

- fermentation to the desired acidity. Briefly, the method begins with raw milk which may also contain a combination of whole milk, skimmed milk, condensed milk, dry milk (defatted dry extract of milk or equivalent) , category A lactoserum, cream and/or other milk fraction ingredients, such as, for example, buttermilk, lactoserum, lactose, lactalbumin, lactoglobulin or lactoserum modified by complete or partial removal of lactose and/or minerals or other milk ingredients so as to increase the defatted solid content, which are mixed so as to provide the desired fat and solid contents. Although not preferred in the context of the present invention, the milk base may contain a filling milk constituent, i.e. a milk ingredient of which a portion consists of a non-milk ingredient, for instance an oil or soya milk.

In a particular embodiment of the invention, the mixing in step (B) is carried out using a static mixer, advantageously with an opening/structure for passing through that is suitable for the chocolate pieces, or a dynamic mixer. Advantageously, it is a dynamic mixer.

Advantageously, the product obtained in step (C) comprises no additive or preserving agent. Advantageously, it contains no alcohol. Advantageously, the milk product obtained in step (C) contains between 0.5 and 6% by weight of chocolate pieces relative to the total weight of the milk product, advantageously between 1 and 4% by weight. It may advantageously have the composition indicated in table 7 below: Table 7 : % composi tion, by weight, of the product obtained in step (C)

In a particular embodiment of the invention, the method according to the present invention comprises an additional step (D) consisting of the metering of the product obtained in step (C) into a thermoformed or preformed decontaminated pot. The pot is therefore thermoformed just before filling, or is a preformed decontaminated pot.

Sealing is then carried out. This entire step (D) takes place in an environment in which the microorganisms are filtered out, advantageously under a laminar flow hood that delivers sterile air under slightly reduced pressure, as conventionally in the fresh milk products industry.

In a particular embodiment of the invention, the method according to the present invention comprises an intermediate step (Cl) consisting of buffer storage of the product obtained in step (C) , advantageously in a small buffer tank.

In a particular embodiment of the invention, the method according to the present invention comprises an additional step (E) consisting of optional cooling to a temperature of between 1 and 10⁰C, and of storage at a temperature of between 1 and 10⁰C, of the fresh milk product.

The invention will be understood more clearly and the aims, advantages and characteristics thereof will emerge more clearly from the description which follows and which is given with reference to the attached drawings representing nonlimiting examples of implementation of the invention, and in which:

Figure 1 represents a first example of a device for implementing pasteurization step (a) and step (b) and optional steps (α) and (al) of the method according to the present invention, step (a) consisting of a batchwise dry pasteurization.

Figure 2 represents a second example of a device for implementing pasteurization step (a) and step (b) and optionally steps (α) and (al) of the method according to the present invention, step (a) consisting of a batchwise dry pasteurization.

Figure 3 represents a device for implementing pasteurization step (a) and step (b) and optional steps (al) and (α) of the method according to the present invention, step (a) being a continuous dry pasteurization.

Figure 4 represents a device for implementing steps (c) , (d) and (e) of the method according to the present invention.

Figure 5 represents a first example of the device for implementing step (e) of the method according to the present invention. Figure 6 represents a second example of a device for implementing step (e) of the method according to the present invention.

Figure 7 represents a third example of a device for implementing step (e) of the method according to the present invention.

Figure 8 represents a rod box, i.e. a specific dynamic mill that can be used in the context of the present invention and that appears to be the most suitable for cutting chocolate strips in a rectangular cross section with a width > 7 mm (it is then necessary to cut widthwise and lengthwise) .

The aim of the device represented in figure 1 is to pasteurize and cool (steps (a) and (b) ) and optionally to prepare and store (steps (α) and (al) ) the chocolate according to the method of the present invention.

This device comprises an inlet (7) , for the ingredients intended for the preparation of the chocolate, a tank (8) for preparing and storing the unpasteurized chocolate, an outlet (9) for the prepared chocolate, a tank (10) for pasteurization and storage of the chocolate under pressure, mounted on scales (11) , an inlet (12) for sterile nitrogen, a vent (13) allowing the gases to leave, equipped with a valve (14) , an outlet (15) for the pasteurized chocolate, equipped with a valve (16) , a pipe

A equipped with a pump (17) , with 500 μm filters (18) , with a mass flow meter (19) , and with a heat exchanger

(20) (heating of the chocolate during pasteurization, cooling during injection) , a pipe C, a 3-way valve (21) , and a pipe B equipped with a nonreturn valve (22) and with an outlet to the injecting device or the metering device (23 ) .

The chocolate can be prepared in the tank (8) by addition of the ingredients in bulk via the inlet (7) . This tank (8) is a stirred tank with a double-walled jacket, mounted on scales (11) , which can also enable storage before pasteurization, for example at 50⁰C. The transfer via the outlet (9) into the pasteurization tank (10) can take place by gravity, overpressure, or using a pump. Alternatively, the tank (8) does not exist and its preparation takes place directly in the pasteurization tank (10) , the ingredients entering via the pipework (9) .

The, pasteurized chocolate remains stored in the pasteurization tank (10) : this avoids a tank having to be pasteurized downstream, and the tank (10) is thus pasteurized at each batch at the same time as the chocolate. Since the chocolate is anhydrous, it is not necessary to clean between two batches, unless the flavors or colors are incompatible. There is thus no loss of time due to cleaning/pasteurization of the tank (10) . In order to prevent any recontamination, the tank (10) is pressurized by means of a sterile gas source (typically 10 to 30 KPa relative) .

Since the chocolate is incompatible with water, the preferred variant consists in pasteurizing all the pipework (A, C, (9) , (12) , (13) , (15) ) dry, in particular at the same time as the pasteurization of the chocolate at each batch, since the circulation, during the pasteurization, in tubes A and C (double-walled jackets with preferably the same heating fluid as the pasteurization tank (10) ) . In order to improve the heat exchange and to limit sedimentation, in particular for chocolates with the high fat content, which are very fluid, these pipes will be either small in diameter relative to the flow rate (as high a rate as possible) , or equipped with static mixers, or with sterile compressed air pumps (for example, 20 s every 10 min in the event of no movement) .

The heat exchanger (20) is optional: it may make it possible to accelerate heat exchanges, in particular when the surface/volume ratio of the tank (10) is unfavorable (large capacity) . Preferably, it will be of scraped surface type, so as to also be used in cooling (tempering) in step (b) of the method according to the present invention. An overpressure in the circuit will prevent recontamination via the revolving mechanical fittings.

Then it remains just to pasteurize the pipework B and its accessories downstream of the point X. In a .1st variant, this part B will be as short as possible, if possible reduced to less than 20 cm in length corresponding to the valve (21) , the nonreturn valve (22) , the pipework B and the outlet to the injecting device/metering device (23) , which will preferably also be pasteurized dry (double- walled jacket at 100°C/l0 to 20 min, after cleaning or without cleaning.

The nonreturn valve (22) prevents the chocolate (anhydrous) from being contaminated with the water from the sweetened aqueous preparation in the event of reverse pressure.

Alternatively, the pipework B downstream of the point X can also be pasteurized conventionally by cleaning in place, and then pasteurization with hot water or steam: however, it is necessary to eliminate the water and preferably to dry the installation before sending the chocolate thereto (stream of sterile gas, or vacuum, heated with double-walled jacket, for example filled with steam at 100 KPa in absolute pressure.

Alternatively, the valve (16) can remain closed during the pasteurization and the return C is then nonexistent: it is then necessary to clean/sterilize/dry the entire installation downstream of the point S, conventionally as indicated above.

Other dry sterilization techniques exist, for example with hot fat (100°C/l0 min) .

The double-walled jacket of the pipework C will advantageously be at a minimum temperature of 4O⁰C, so as to prevent crystallization in the pipe, especially when the metering is carried out at a temperature <35°C. The valve (21) (3-way) closes the pipework C when the chocolate is injected into the sweetened aqueous preparation: this makes it possible to determine the flow rate injected via the flow meter (19) . Preferably, the pump (17) is controlled by the flow rate indicated by the flow meter (19) .

Ideally, the tank (10) is on scales (11) so as to facilitate the management of the ingredients, in particular the use of pasteurized chocolate.

Alternatively, level detectors (capacities, vibrating bimetal, etc.) will perform the same function. All the pipework (A, B, C, (9) , (13) , (15) , (7) , (12)) /tanks

((10), (8))/, accessories for chocolate have a double- walled water jacket (preferred variant) , or even have trace heating using strip electrical resistors (less well regulated) .

The flow rate of chocolate should be even when injected.

The device in figure 2 comprises a pasteurization and storage tank (10) which is not pressurized, mounted on scales (11) , an inlet (9) for the ingredients for producing the chocolate, a permanent vent (12) equipped with a sterile filter (24) , an outlet (15) for the pasteurized chocolate, equipped with a valve (16) , a pipe

(20) , a pipe C, a 3-way valve (21) , and a pipe B equipped with a nonreturn valve (22) and with an outlet (23) to the injecting device and the metering device.

The tank (10) is not pressurized (and therefore less expensive) , and has been constructed with respect to less strict standards in terms of hygiene than the tank in figure 1. It is connected to ambient air via a sterile filter (24) that acts as a vent (12) to eliminate the steam. After pasteurization, the chocolate is stored at

70-75⁰C without overpressure (this kills any possible recontaminants) and is then cooled on line before injection, with 2 variants:

• cooling to 31-40⁰C (double-walled water jacket at 28-39⁰C), preferably 35-38⁰C, by means of any exchanger (20) (tubular or scraped surface, or even plates) ; • cooling of the chocolate to 24-31°C by means of a scraped surface exchanger (20) (preferred variant, since the temperature is lower, and crystallization is therefore more rapid) .

The pipework A between the point S and the heat exchanger (20) and C will also be maintained at 70°C-75°C for microbiological reasons (no recontamination in the event of a leak in the pump (17) ) .

The scales (11) are optional and can be replaced with off¬ line weighing out, or else flow meters. The 500 μm filters (18) and the flow meter (19) are optional.

In figures 1 and 2, it is possible to store the pasteurized chocolate in an intermediate buffer tank placed between the valve (16) and the heat exchanger (20)

(failing this, the point X) : if the storage is carried out at less than 75°C, it will then have to be pasteurized during the 1st use and at each loss of the pasteurized state (since the chocolate is virtually anhydrous, no microbial growth can take place, except in an exceptional case: maintenance, etc.) . This may be carried out conventionally (cleaning, then hot water sanitization, then evaporation) , or preferably by heating, providing an Fz > 6000 min (for example, 22 h at 75°C) , preferably Fz > 20 000 min.

It is also possible to permanently store the chocolate from this tank at 75⁰C so as to have "continuous" pasteurization.

Figure 3 represents a device comprising a tank (8) for preparation and storage of the unpasteurized chocolate, mounted on scales (11) , an inlet (7) for the ingredients for preparing the chocolate, an outlet (9) for the unpasteurized prepared chocolate, equipped with a valve

(16) , a pipe A equipped with a pump (17) , with a mass flow meter (19) , with 500 μm filters (18) , with a heat exchanger for the heating and the pasteurization (25) , and with a heat exchanger for the cooling (20) , a pipe C equipped with a nonreturn valve (26) , a 3-way valve (21) and a pipe B equipped with a nonreturn valve (22) and with an outlet to the injecting device or the metering device

(23) . When the device is run, the part between the pasteurizing device (heat exchanger (25) ) and the nonreturn valve (26) of the pipe C is pasteurized by heating the entire conduit at 100°C/20 min. Only then is the cooling device (heat exchanger (20) ) turned on and the valve (16) opened in order to use the chocolate. If the injection is stopped for a few minutes, the chocolate is recycled via the pipework C, the double-wall jacket of which is at 50⁰C. Alternatively, a buffer tank at 7O⁰C + delivery pump can be added before the heat exchanger intended for the cooling (20) . The part of the pipework C downstream of the nonreturn valve (26) is considered to be unpasteurized. Furthermore, in this device, it is advisable to take precautions in the pipework using agitation due to the speed, air or static mixers. Ideally, the pipework C, which is not always fed, will be sloping so as to self-empty, or will be equipped with static mixers.

Figure 4 describes a device for injecting the chocolate into the sweetened aqueous preparation. It comprises the inlets (27 and 28) for the sweetened aqueous preparation, the inlet (29) of the chocolate, a nonreturn valve (22) , a device (30) for injecting the chocolate, a device (31) for solidifying the chocolate, a dynamic mill (32) and an outlet (33) for the sweetened aqueous preparation containing chocolate pieces.

The nonreturn valve (22) prevents entry of the water into the pasteurized chocolate under any circumstances. It is located just before the injecting device (30) .

The inlet for the sweetened aqueous preparation is in two parts (27 and 28) which are then combined into a single line so as to inject the chocolate at the center of this coming together. The device (31) for solidifying the chocolate consists of a tube that has a double-walled jacket containing water at a temperature of between 1 and 4⁰C. The dynamic mill (32) used in this device is a worm.

The arrows used in the scheme indicate the direction of circulation of the streams of sweetened aqueous preparation and of the product containing the chocolate pieces.

Figure 5 represents an enlargement of the dynamic mill device (32) in figure 4, which, in this case, consists of a worm. Moreover, this device also comprises a deflector/support blade (34) just before the inlet for the stream consisting of the sweetened aqueous preparation (36) and the solidified chocolate strip (35) into the dynamic mill (32) .

The arrows used in this scheme indicate the direction of circulation of the streams of sweetened aqueous preparation (36) + solidified chocolate strip (35) and of the product containing the chocolate pieces.

Figure 6 represents a device similar to that of figure 5, except that the dynamic mill (32) consists of rotary blades.

Figure 7 represents a device similar to that of figures 5 and 6, except that the dynamic mill (32) consists of a propeller and that the deflector/support blade (34) has holes in it so as to allow the sweetened aqueous preparation (36) to pass through.

The following examples are given by way of nonlimiting indication.

Example 1

300 kg of chocolate (formula 2 in table 3) are produced, pasteurized, cooled and stored in the same 500 1 tank equipped with a double-walled jacket and with a stirrer that scrapes the walls (batch) (figure 2) . The initial natural mold and yeast contamination of the chocolate is 45 cfu/g.

The preparation of the chocolate follows the steps below:

Blocks of 25 kg of solid cocoa butter (20⁰C) are melted in the closed tank (10) , the double-walled jacket being supplied with steam at 100-110⁰C so as to accelerate the melting. Once said cocoa butter is molten, the other solid ingredients (chocolate, cocoa paste) , purchased as "easy melt" (chips, or pieces typically of 1 to 30 g) , are melted into the cocoa butter at approximately 100⁰C and the double-walled jacket is regulated at 75⁰C. Once all the ingredients are molten, the stirring (maximum) is then started out in order to homogenize the chocolate and prevent settling out.

The tank (10) is closed, the pump (17) starts up so as to provide circulation in the pipeworks A and C, and the chocolate, subjected to maximum stirring, is brought to

100⁰C by heating via the double-walled jacket supplied with steam (vapor pressure 120 KPa in absolute pressure) .

When a temperature of 100⁰C is reached at all points (tank

(10) and outlet pipework C) , it is maintained for 10 minutes. The tank 10 is permanently opened to the air by means of a vent (12) via sterile filter (24) . The chocolate, the tank (10) and the pipe up to the point X are then pasteurized.

The chocolate is then cooled and maintained at 7O⁰C by regulating the water in the double-walled jacket. The taste of the chocolate has not been substantially modified by the pasteurization.

The residual contamination thereof is less than 1 cfu per 100 g. The method for counting yeast + molds ("25°C/5+5" method) is as follows:

The yeast and mold contamination is counted by diluting the chocolate to 1/lOth in a conventional "malt extract" medium (mixture at 4O⁰C so that the chocolate is clearly fluid) , and then enriching (the molds/yeast initially present) at 25°C/5 days with agitation (molds are aerobic) . At the end of this, 1 ml is taken and deposited on a "malt extract agar" medium and incubated at

25°C/5 days. The presence or absence of contaminant

(yeasts/molds) is then noted.

In the present case, using this method, the absence of molds/yeast in 100 g is noted.

The chocolate is cooled to 26°C by means of a scraped surface heat exchanger located just before the injecting device, and is then injected (round nozzle with a diameter of 5.6 mm, according to the device in figure 4) into a sweetened aqueous preparation. Chocolate and preparation have the same speed in the crystallization tube.

This sweetened and flavored aqueous preparation contains (without the chocolate) 20% by weight of sucrose and 30% by weight (dry equivalent) of invert sugars, flavorings, a gel-forming agent (0.7% by weight of LM pectin) and two thickeners (3% by weight of a modified starch such as acetylated distarch adipate (<5% by weight, preferably 1 to 4% by weight) and 0.2% by weight of carob flour) . The water content is 46%. The pH is adjusted by adding citric acid such that the former is 4.5 after the 3 weeks of storage of the sweetened aqueous preparation + chocolate pieces. A calcium salt is introduced in order to functionalize the pectin to a maximum. The freezing point is -4.2⁰C. This sweetened aqueous preparation is cooled to -2⁰C by means of a tubular exchanger. The nozzle injecting the chocolate is insulated with respect to the sweetened aqueous preparation by means of a double-walled jacket supplied with water at 28⁰C.

During the 1st passage, 5% by weight of chocolate is injected into the sweetened aqueous preparation. The crystallization takes place in a linear tube with a double-walled jacket at -I⁰C. After crystallization and cooling to 11°C, the chocolate ribbon is milled in a dynamic mill (32) consisting of an endless screw equipped with a counterblade (figure 5) . At least 90% by weight of the chocolate pieces are <8 mm.

The crystallization time is approximately 80 s.

Two other passages are carried out in order to obtain 15% by weight of chocolate in the sweetened aqueous preparation.

The sweetened aqueous preparation containing chocolate pieces is stored for 3 weeks at 10⁰C, and is then used for metering: 80% by weight of a sweetened yoghurt (containing 8% by weight of sugar) at 14⁰C + 20% by weight of the sweetened aqueous preparation with chocolate pieces, using a Dosys^" as dynamic mixer.

It is possible to store the sweetened aqueous preparation containing chocolate pieces for a few hours (according to the size of the container) at 18°C just before its use, in order to reduce its viscosity and facilitate the pumping thereof.

The yoghurt used has the composition indicated in table 8 below: Table 8: % composition, by weight, of the yoghurt

Ingredients %

Skimmed milk containing 0.5 g/1 of fat 54 .73

Cream containing 400 g/1 of fat 14 .72

Skimmed milk powder 6. 59

Sugar 8

Water 15 .67

Gelatin 250°Bloom 0. 25

Lactic culture 542 Oil 0. 02

It has the characteristics given in table 9 below:

Table 9: Characteristics of the yoghurt as % by weight

The flavored sweetened yoghurt containing chocolate pieces thus obtained is metered into uncontaminated pots under a laminar flow hood (conventional yoghurt process) and can be conserved (without preserving agents) for up to 30 days at a maximum of 10⁰C.

Example 2 :

The method is identical to that of example 1, except for the following differences: the sweetened aqueous preparation containing chocolate pieces is stored for 3 weeks at 1O⁰C, and then metered as superimposed bilayers (therefore without mixing) into a pot :

20% by weight of the sweetened aqueous preparation with chocolate pieces,

80% by weight of a sweetened yoghurt (containing 8% by weight of sugar) . The flavored sweetened yoghurt containing chocolate pieces thus obtained is metered into pots, and can be conserved (without preserving agents) for up to 30 days at a maximum of 1O⁰C.

Example 3

The composition of the chocolate is given in table 10 below:

Table 10: % composition, by weight, of the chocolate

In these formulae:

- the cocoa mass contains, as % by weight: 1.7% of water, 53.4% of fat and 44.95% of dried defatted cocoa; the water content thereof is <1%, the particle size thereof is fine

(minimum of 90% of particles < 20 μm; maximum of 0.2% of particles > 75 μm) ;

- the dark chocolate contains, as % by weight: 0.5% of water, 27.7% of fat (of which approximately 0.3% lecithin) , 22.3% of dried defatted cocoa and 49.5% of sugar; preferably, its particle size using a Palmer is < 30 μm.

Advantageously, these two constituents and the cocoa butter are sold by the company Barry-Callebaut .

The initial natural mold and yeast contamination of this chocolate is 75 cfu/g.

300 kg of final chocolate (75% of fat) are produced, pasteurized, cooled and stored in the same 500 1 tank equipped with a double-walled jacket and a stirrer that scrapes the walls (batch) (figure 1) .

The preparation of the chocolate is carried out in the following way:

Blocks of 25 kg of solid cocoa butter (2O⁰C) are melted in the closed tank (10), the double-walled jacket being supplied with steam at 100-110⁰C so as to accelerate the melting. Once said cocoa butter is molten, the other solid ingredients (chocolate, cocoa paste) , purchased as "easy melt" (chips, or pieces typically of 1 to 30 g) , are melted into the cocoa butter at approximately 100⁰C and the double-walled jacket is regulated at 75⁰C. Once all the ingredients are molten, the stirring (maximum) is then started up in order to homogenize the chocolate and prevent settling out.

The tank (10) is closed, the pump (17) starts up so as to provide circulation in the pipeworks A and C, and the chocolate, subjected to maximum stirring, is brought to 100⁰C by heating via the double-walled jacket supplied with steam (vapor pressure 110 KPa in absolute pressure) .

When a temperature of 100⁰C is reached at all points (tank

(10) and outlet pipework C) , it is maintained for

5 minutes (F_z = 41700 min) , and the tank (10) is opened to the air by means of a vent (13) via a sterile filter so as to eliminate the steam. The tank (10) is then closed again and is placed under a nitrogen pressure (12) via a sterile filter, the pressure being regulated at 120 KPa in absolute pressure until the production of the next batch, so as to prevent any entry of gas or of material from the outside which could recontaminate the pasteurized product.

The chocolate is then immediately cooled to 33⁰C by regulation of the water inlet into the double-walled jacket, and is maintained at 33⁰C until use (within 24 h) .

The taste of the chocolate has not been substantially modified by the pasteurization.

The residual contamination, measured by the same method as in example 1, is less than 1 cfu/300 g, i.e. a decrease of 4.3 log.

The chocolate is cooled on line to 26⁰C on a scraped surface heat exchanger (20), and is then injected into the sweetened aqueous preparation (same formula as example 1) at -2°C, via a 6.5 mm nozzle (insulated by a double-walled jacket at 28⁰C) , in a crystallization tube that has a double-walled jacket and an internal diameter of 8 mm. The double-walled jacket is supplied with ice-cold water at -2⁰C. At this stage, there is 75% by weight of chocolate and 25% by weight of sweetened aqueous preparation.

A cylinder of chocolate 6.9 mm in diameter is formed at the center of a ring of sweetened aqueous preparation, and the time taken to pass through the crystallization tube is 181 s, for a chocolate flow rate of 6 kg/h. Just at the outlet of the crystallization tube, the cylinder of solidified chocolate is cut by the shearing of the blades of a centrifugal pump used as a dynamic mill. The speed of rotation is adjusted so as to obtain chocolate "cylinders" that are approximately 8 mm long. It is also possible to increase the number of blades (usually 2 spokes) up to 10 spokes, so as to reduce the speed of rotation.

Additional sweetened aqueous preparation at 4⁰C reaches the centrifugal pump, at a flow rate of 44 kg/h, and mixes with the chocolate pieces, which gives a sweetened aqueous preparation containing 12% by weight of chocolate pieces. The mixture is stored in mobile containers, conserved for up to 3 weeks at 4⁰C.

In order to increase the flow rate of the line, it is sufficient to place several crystallization tubes in parallel. For example, a flow rate of 132 kg/h of sweetened aqueous preparation could be mixed in the centrifugal pump with the solidified chocolate originating from 3 crystallization tubes, each at 6 kg/h.

The use in a sweetened yoghurt is identical to that of example 1.

Claims

WHAT IS CLAIMED IS:

1. A method for producing a sweetened aqueous preparation in which 8 to 30% by weight, advantageously 10 to 30% by weight, advantageously 10 to 20% by weight, relative to the total weight of the preparation, of chocolate pieces are dispersed, which method comprises the following successive steps:

a) pasteurization of the chocolate having a fat content of between 43 and 85% by weight, advantageously between 68 and 78% by weight, with a pasteurization strength Fz of between 6000 and 10 000 000 min, advantageously between 10 000 and 500 000 min, even more advantageously between 15 000 and 100 000 min,

or sterilization of the chocolate having a fat content of between 43 and 85% by weight, advantageously between 68 and 78% by weight;

b) cooling of the pasteurized or sterilized chocolate to a temperature of between 24 and 45°C, advantageously between 24 and 38⁰C;

d) solidification of the pasteurized or sterilized chocolate injected;

e) optionally cutting and mixing of the injected and solidified, pasteurized or sterilized chocolate in the pasteurized or sterilized, sweetened aqueous preparation;

f) recovery of a sweetened aqueous preparation in which 8 to 30% by weight, advantageously 10 to 30% by weight, advantageously 10 to 20% by weight, relative to the total weight of the preparation, of chocolate pieces having a fat content of between 43 and 85% by weight, advantageously between 68 and 78% by weight, are dispersed, said preparation being conserved at a temperature of less than 1O⁰C for at least 3 weeks.

2. The method as claimed in claim 1, wherein the chocolate has a parameter (τ) less than 3, advantageously less than 2, advantageously less than 1, the parameter (τ) being defined by the following equation (1) : τ= (- [water] + 0.37) x F + (5.25 x [water] - 1.67) x (S+SMP) + (26.2 x [water] - 9.6) x C + (61 x [water] - 14.5) x (S+SMP) x C, with:

[water] is the local free water content of the final fresh milk product (in g/g) ,

F is the fat content of the chocolate (in g/g) , - S + SMP is the content of sugars + skimmed milk powder of the chocolate (g/g) ,

C is the content of dry and defatted cocoa of the chocolate (in g/g) .

3. The method as claimed in claim 1 or 2, wherein the chocolate has a C/ (S+SMP) ratio < 2.3, advantageously less than 1.6, even more advantageously less than 1.

4. The method as claimed in any one of the preceding claims, wherein the pasteurization step (a) is carried out dry.

5. The method as claimed in any one of the preceding claims, wherein step (b) consists in tempering and cooling the chocolate to a temperature of between 24 and 30°.

6. The method as claimed in any one of the preceding claims, wherein the sweetened aqueous preparation (excluding chocolate pieces) has an Aw measured at 25⁰C of less than 0.93.

7. The method as claimed in any one of the preceding claims, wherein step (c) is carried out by continuous injection of the chocolate in the form of strips into the sweetened aqueous preparation, and wherein step (e) consists of the injected and solidified, pasteurized or sterilized chocolate being cut into pieces and mixed into the pasteurized or sterilized, sweetened aqueous preparation by means of a dynamic mill.

8. The method as claimed in claim 7, wherein step (c) is carried out by injection of the chocolate into the middle of the stream of the sweetened aqueous preparation, the stream of chocolate being parallel to the stream of sweetened aqueous preparation and the linear speed of the stream of chocolate on leaving the injecting device being equal, to within ± 40%, to that of the stream of sweetened aqueous preparation.

9. The method as claimed in any one of the preceding claims, wherein a large amount of chocolate is injected in step (c) by proportion to the sweetened aqueous preparation and the rest of the sweetened aqueous preparation is added in step (e) so as to obtain, in step

(f) , a sweetened aqueous preparation containing the desired amount of chocolate pieces.

10. The method as claimed in any one of claims 7 to 9, wherein the solidification time in step (d) is between 30 and 600 s .

11. The method as claimed in any one of claims 7 to 10, wherein the longest dimension of the chocolate pieces obtained in step (e) is between 1 and 6 mm, advantageously between 4 and 6 mm.

12. The method as claimed in any one of claims 1 to 6, wherein step (c) is carried out by dropwise injection of the chocolate above the pasteurized or sterilized, sweetened aqueous preparation, and wherein step (e) consists in mixing, by stirring, preferably without cutting, the drops of injected and solidified, pasteurized or sterilized chocolate into the pasteurized or sterilized, sweetened aqueous preparation.

13. The method as claimed in any one of the preceding claims, which method comprises an intermediate step (al) between steps (a) and (b) , consisting of storage with stirring of the pasteurized chocolate at a temperature of between 28 and 75°C, advantageously between 65 and 75°C, optionally without overpressure.

14. The method as claimed in any one of the preceding claims, which method comprises an additional step (g) consisting of storage of the sweetened aqueous preparation in which 8 to 30% by weight, advantageously 10 to 30% by weight, advantageously 10 to 20% by weight, relative to the total weight of the preparation, of chocolate pieces obtained in step (f) are dispersed, at a temperature of between 0 and 10⁰C, advantageously between 0 and 4⁰C.

15. The method as claimed in claim 14, wherein the storage step (g) is carried out in mobile containers without stirring.

16. The method as claimed in any one of the preceding claims, which method comprises a step (α) , prior to step (a) , consisting of preparation of the chocolate, advantageously by mixing the fat and the dark chocolate and, optionally, the cocoa mass and/or the cocoa powder.

17. The method as claimed in any one of the preceding claims, wherein the same tank is used for steps (α) , (a) and (al) .

18. The method as claimed in any one of the preceding claims, which method is carried out in a device that has a nonreturn valve for separating the stream of chocolate obtained in step (b) from the stream of sweetened aqueous preparation.

19. The method as claimed in any one of the preceding claims, wherein steps (c) to (e) are repeated at least once before step (f) , the stream of sweetened aqueous preparation containing less than 8 to 30% by weight, advantageously less than 10 to 20% by weight of chocolate obtained in step (e) being re-used in steps (c) to (e) , as pasteurized or sterilized, cooled sweetened aqueous preparation.

20. A method for producing an acidic or neutral fresh milk product containing chocolate pieces, which method comprises the following steps:

A) production of a sweetened aqueous preparation in which 8 to 30% by weight, advantageously 10 to 30% by weight, advantageously 10 to 20% by weight, relative to the total weight of the preparation, of chocolate pieces are dispersed, by carrying out steps (a) to (f) and optional steps (α) , (al) and/or (g) as claimed in any one of claims 1 to 19; (B) injection of the sweetened aqueous preparation containing chocolate pieces and having a temperature of < 2O⁰C, advantageously equal to 17⁰C +/- 3°C, in contact with a stream of acidic or neutral, pasteurized milk base having a temperature of less than 2O⁰C, preferably < 15°C, and optional mixing of the sweetened aqueous preparation and of the milk base;

(C) recovery of an acidic or neutral fresh milk product containing chocolate pieces having a fat content of between 43 and 85% by weight, advantageously between 68 and 78% by weight, said product being conserved at a temperature of between 1 and 10⁰C for a period of between 12 days and 6 weeks.

21. The method as claimed in claim 20, wherein the acidic milk base is a fermented product containing live ferments, and in particular a yoghurt.

22. The method as claimed in either one of claims 20 and 21, which method comprises an additional step (D) consisting of the metering of the product obtained in step (C) into a thermoformed or preformed decontaminated pot.

23. The method as claimed in any one of claims 20 to 22, wherein the acidic or neutral fresh milk product obtained in step (C) contains between 0.5 and 6% by weight, advantageously between 1 and 4% by weight, relative to the total weight of the product, of chocolate pieces.