WO2018117911A1

WO2018117911A1 - Method for sour cream production using baked cream

Info

Publication number: WO2018117911A1
Application number: PCT/RU2017/000958
Authority: WO
Inventors: Natalya Valerevna VOROPAEVA; Nina Aleksandrovna AKOVBYAN; Aleksandr Vladimirovich PESKIN
Original assignee: Aktsionernoe Obshchestvo "Danon Russia"
Priority date: 2016-12-21
Filing date: 2017-12-21
Publication date: 2018-06-28
Also published as: RU2677781C2; RU2016150336A3; RU2016150336A; EA201991140A1

Abstract

The invention relates to dairy products industry, specifically, to baked sour cream production technology.

Description

Method of Sour Cream Production Using Baked Cream.

The invention relates to dairy products industry, specifically, to baked cream based sour cream production technology.

The prior art discloses multiple different means for sour cream production.

Thus, for instance, Patent RU 2126635 CI, A23C 13/16, published on 27.02.1999 discloses the method of sour cream production which involves dairy cream standardization in terms of fat content, its pasteurization, homogenization, cooling to fermentation temperature, agitation to uniform consistency, introduction of the ferment mix, lactic-acid culture ferment for sour cream, and dry bacterial concentrate of mesophilic and thermophilic lactic streptococcus which are taken in equal doses to the number of 5- 10% of the total mass, agitation, fermentation to obtain the finished product with acidity of 60-105 °T, packaging, and ageing.

Patent RU 94024140 Al, A23C 13/12, published on 27.06.1996 discloses the method of sour cream production which involves dairy cream standardization in terms of fat content, its pasteurization, homogenization, cooling to fermentation temperature of 33-35 °C, introduction of the ferment containing vitamin B complex producers, agitation for max. 10 min., fermentation at 30-32 °C for 4-7 hours, repeated agitation for max. 3 min., packaging, and maturation.

Patent SU 1757567 Al, A23C 13/16, published on 30.08.1992, discloses the method of sour cream production which involves dairy cream standardization in terms of fat content, its pasteurization, homogenization, cooling to fermentation temperature, introduction of ferment mixture, fermentation, agitation, packaging, and maturation.

However, the prior art does not disclose the method of sour cream production using baked cream.

The objective of this claimed invention is the development of a new method for the manufacture of a new product, i.e. a fermented milk product having both baked and sour cream characteristics.

The technical result of the claimed invention lies in manufacture of the product, specifically, baked cream-based sour cream having a dense sticking consistency, taste and aroma of baked cream. The technical result is achieved by the baked cream-based sour cream preparation method provided herein.

Accordingly the present invention provides a method for the preparation of a fermented milk product comprising the following steps

i) providing a milk composition having at least 5% by weight fat

ii) treating the milk composition by means of lactase to provide a milk composition having 3% by weight or less lactose

iii) heat treating the milk composition for at least 2 hours at a temperature of at least 90°C

iv) fermenting the milk composition by means of lactic acid bacteria to provide a fermented product Detailed description In a first aspect the present invention provides a method comprising:

i) providing a milk composition having at least 5% by weight fat

In a first step a milk composition is provided, said composition comprising at least 5%, 10%, 15%, 20%, 25%, 30%, 35% or 40% fat by weight, hereinafter said milk composition is also referred to as "cream", "standardized cream" or "heavy cream". The milk composition is typically comprised of milk and/or ingredients obtained from milk.

In the present specification, unless otherwise specified, percentages are percentages by weight..

As used herein the term "milk" encompasses animal milk, such as cow's milk.

Milk compositions useful in such products and/or processes are known by the one skilled in the art of dairy products, preferably of fermented dairy products. Herein a milk composition encompasses a composition of a milk fraction obtained by fractionating whole milk into a plurality of fractions having a desired fat content. Alternatively the term also encompasses compositions obtained by mixing several previously separated milk fractions. Some water or some additives can be added to said milk fractions and mixtures. Preferably the milk is an animal milk, for example cow's milk, sheep milk or goat milk.

The milk composition can typically comprise ingredients selected from the group consisting of milk, half skimmed milk, skimmed milk, milk powder, skimmed milk powder, milk concentrate, skim milk concentrate, milk proteins, cream, buttermilk and mixtures thereof. The milk composition can typically have a fat content of from 5% to 40% by weight, for example of from 10% to 30% or from 10%) to 20%. The "fat content" of a composition corresponds to the weight of the fat components present in the composition relatively to the total weight of the composition. The fat content is expressed as a weight percentage. The fat content can be measured by the Weibull-Berntrop gravimetric method described in the standard NF ISO 8262-3. Usually the fat content is known for all the ingredients used to prepare the composition, and the fat content of the product can be calculated from these data.

The milk composition can typically have a protein content of from 2.0% to 6.0% by weight, for example of from 2.0% to 3.0% or from 3.0% to 4.0%). The "protein content" of a composition corresponds to the weight of the proteins present in the composition relatively to the total weight of the composition. The protein content is expressed as a weight percentage. The protein content can be measured by Kjeldahl analysis (NF EN ISO 8968-1) as the reference method for the determination of the protein content of dairy products based on measurement of total nitrogen. Nitrogen is multiplied by a factor, typically 6.38, to express the results as total protein. The method is described in both AOAC Method 991.20 (1) and international Dairy Federation Standard (IDF) 20B: 1993. Usually the total protein content is known for all the ingredients used to prepare the product, and total protein content can be calculated from these data.

The milk composition, can comprise lactose. The amount of lactose can be typically from 3.80% to 5.00% by weight.

In one such embodiment said milk composition may be prepared by means of the following steps. Base raw milk enters a vessel, then it flows through filtering materials for purification, then the raw milk is subjected to the initial treatment. Upon determination of quality indicators and weight, the accepted raw milk is purified, i.e. cleaned from mechanical impurities using centrifuge milk purifiers or filtering materials. Then the milk is processed or cooled down to a temperature of (4 ± 2) °C.

The original milk preferably at a temperature of 35 - 40 °C is subjected to separation into heavy cream and skimmed milk. The cream is standardized in terms of fat weight fraction to provide a cream comprising 5%, 10%, 15%, 20%, 25%, 30%, 35% or 40% fat by weight. This may be carried out in a standardizing separator using an automatic standardization system, or in tank by mixing heavy cream and skimmed milk so that the finished product has the fat weight ratio at least the same as prescribed by the formulation of the product type in question. ii) treating the milk composition by means of lactase to provide a milk composition having 3% or less lactose by weight

In a second step the milk composition is treated by means of lactase such that the lactose content is reduced, preferably to provide a milk composition having less than 3%, 2%, 1.5%, 1%, 0.5%, 0.2% or 0.1% lactose by weight. It is particularly preferred that the lactose content is 1.5% or less by weight. Conversion of lactose to glucose and galactose provides a final product having improved baked notes in the flavor profile as well as a characteristic "baked" colour as a result of the heat treatment to be carried out in step iii).

Such lactase hydrolysis operations are known by the one skilled in the art, suitable lactase enzyme preparations are known by the one skilled in the art and are commercially available. The hydrolysis temperature can be from about 4°C to 40°C. The hydrolysis time may be about from 12 - 2 hours.

Suitable lactase enzymes include for example "HA LACTASE 5200" lactase enzyme manufactured by "Christian Hansen" / "MAXILACT LG 5000" or other enzymes having other activity units (NLU/1), which is calculated on the basis of the required lactose hydrolysis in the cream. For instance, in order to achieve the lactose content below 0.1% using "HA LACTASE 5200", it is possible to take 500 ml of lactase per 1000 1 of standardized cream with initial lactose content of 4.0%.

After lactase introduction, standardized cream is subjected to lactose hydrolysis by time- temperature treatment preferably under continuous agitation / stirring. The hydrolysis process may take place under any suitable conditions e.g. a temperature of 4 - 6 °C for 12 hours, or at a temperature of 38 - 40 °C for 2 hours.

Optionally the hydrolyzed cream is homogenized preferably at a temperature of 60 - 75 °C and pressure of 13.0 - 15.0 MPa, optionally the cream may be pasteurized preferably at a temperature of 95 - 97 °C.

In a third step the milk composition is subjected to heat treatment at least 90°C, more preferably 90°C to 98°C or even more preferably 92°C to 96°C. In one embodiment the heat treatment is carried out at about 94°C. This treatment is carried out for 2 - 4 hours preferably at least until a visually perceptible change in color can be observed. The color can be determined by comparison to the NCS standard as the reference method for the determination of the color. Preferably the heat treatment is carried out until the milk composition reaches a light golden brown color, for example comparable to NCS S 0510- Y40R or NCS S 1010-Y40R but no darker than NCS S 1015-Y40R as determined using the NCS standard. After said heat treatment (also referred to herein as "baking"), the cream is preferably cooled down to a temperature of 8 - 10 °C. Optionally for the purpose of standardization in terms of protein content, dry skimmed milk or milk protein may be added to provide a cream having at least 2.5%, or more preferably at least 3.5% protein content. In one embodiment the protein content is 3% - 3.5%) e.g. about 3.1% or 3.2%. For faster and more complete dissolution of the dry milk or milk protein, it is preferred to use mixture circulation using a shear pump or any other suitable equipment.

The milk composition is optionally homogenized and heat-treated subsequent to step iii) and prior to step iv). Homogenization is preferably carried out at a temperature of 60 - 75 °C and pressure of 13.0 - 15.0 MPa. Homogenized milk composition may be pasteurized preferably at a temperature of 95 - 97 °C for about 5 minutes. Then the milk composition is preferably cooled down to a fermentation temperature of 28 - 35 °C and optionally delivered to a jacketed tank. iv) fermenting the milk composition by means of lactic acid bacteria to provide a fermented product In a fourth step the milk composition is fermented by means of lactic acid bacteria (also referred to herein as "ferment") to provide a fermented product. Preferably fermentation is stopped when the milk composition reaches suitable pH levels (preferably pH 3.50 to 5.50, even more preferably from pH 4.0 to 5.0).

Fermented dairy compositions are typically obtained by a process involving a fermentation step with at least one lactic acid bacteria. In this step the milk composition is inoculated with the lactic acid bacteria, and the mixture is then allowed to ferment at a fermentation temperature. Such inoculation and fermentation operations are known by the one skilled in the art. It is preferred that the lactic acid bacteria comprise Lactococcus and/or Streptococcus thermophilus, it is particularly preferred that the Lactococcus are selected from Lactococcus Cremoris and/or Lactococcus Lactis.

During fermentation, the lactic acid bacteria produce lactic acid and thus cause a pH decrease. With the pH decreasing proteins coagulate to form a curd, typically at a breaking pH.

The fermentation temperature can be from about 30°C to 45°C, with a pH decrease to a breaking pH at which proteins coagulate to form a curd.

The breaking pH is preferably from 3.50 to 5.50, preferably of from 4.0 to 5.0.

Suitable lactic acid bacteria for milk composition fermentation are known by the one skilled in the art. It is mentioned that lactic acid bacteria are often referred to as ferments, cultures, starter cultures or starters.

Preferably, a ferment consisting or comprising of Lactococcus (preferably Lactococcus Cremoris and/or Lactococcus Lactis) or a mixture of Lactococcus and Streptococcus thermophilus should be introduced. The use of such ferments for the preparation of fermented milk products is within the scope of the skilled person and may be carried out according to the recommendations of the manufacturers. The milk composition may preferably be agitated / stirred for at least 15 minutes, and then the milk composition should preferably be fermented at a temperature of 28 - 35 °C for 6 - 12 hours preferably until a curd is formed. In one embodiment fermentation completion is preferably determined by the presence of curd, acidity (preferably 50-90, even more preferably 50 - 70 or most preferably 60-80°T and pH (4.6 ± 0.5). The fermented milk composition is preferably agitated / stirred until a homogeneous consistency is obtained, e.g. from 3 to 15 minutes, whereupon the mixture is optionally delivered for bottling / packaging. Hereinafter the fermented milk composition is alternatively referred to as "fermented cream", "sour cream" or "fermented mixture". v) optionally the fermented milk composition is packaged

In an optional fifth step the fermented milk composition (also referred to below as "cream") is bottled or packaged. The fermented mixture should be periodically agitated / stirred during bottling / filling. The fermented cream may be partially cooled down to a temperature of 16 - 22 °C by introduction of ice water to the tank jacket and periodic stirring / agitation of the curd, or by cooling down using a plate type cooler.

After packaging and labeling, the fermented mixture should be cooled down, for example in refrigerating chambers to a temperature of (4 ± 2) °C. Product maturation takes place parallel to the cooling down. The time of product cooling and maturation in a refrigeration chamber is within the skill of the person skilled in the art. Upon cooling, the sour cream product is ready for consumption.

Product characteristics

The present invention provides a fermented milk product obtainable according to the process of the invention comprising:

i) at least 5% fat by weight,

ii) 3% or less lactose by weight

iii) at least 3% protein by weight

characterized in that said composition has a pH of less than 5 and a viscosity of at least 1 ,000 mPa, more preferably at least 1,250 mPa.

As used herein the term "viscosity" refers to the viscosity as measured at 10°C, at a shear rate of 64 s-1, preferably after 15 s at this shear rate, for example with a Rheomat 180. Preferably said product has a fat content of at least 5%, 10%, 15%, 20%, 25%, 30%, 35% or 40% by weight.

Preferably said product has a lactose content of 2%, 1.5%, 1%, 0.5%, 0.2% or 0.1% or less by weight. It is particularly preferred that the lactose content of the product is less than 1.5%. by weight. It is preferred that the product of the present invention has a uniform non-white color. Preferably said product has a color comparable to NCS S 0510-Y40R and no darker than NCS S 1015-Y40R of the NCS color standard.

Preferably said product has an acidity of 50-90°T , even more preferably 50 - 70°T or most preferably 60-80°T.

The product is typically contained in a sealed container such as a packaging. The process can typically involve a step of conditioning the product in a container. The container is then typically sealed, for example with a cap or a lid. The container can be for example a container of 50 ml (or 50 g), to 1 L (or 1 kg), for example a container of 50 ml (or 50 g) to 80 ml (or 80 g), or 80 ml (or 80 g) to 100 ml (or lOOg), or 100 ml (or 100 g) to 125 ml (or 125 g), or 125 ml (or 125 g) to 150 ml (or 150 g), or 150 ml (or 150 g) to 200 ml (or 200 g), or 200 ml (or 200 g) to 250 ml (or 250 g), or 250 ml (or 250 g) to 300 ml (or 300 g), or 300 ml (or 300 g) to 500 ml (or 500 g), or 500 ml (or 500 g) to 750 ml (or 750 g(, or 750 ml (or 750 g) to 1 L (or 1kg).

The product can be stored, transported and/or distributed at a chilled temperature of 0°C to 10°C, preferably of 4°C to 10°C. The product may have a shelf-life under such conditions of at least 30 days.

Suitable containers for carrying out the above-mentioned preparation steps are known in the art and are within the scope of the skilled person. These include for example tanks typically used for the preparation of fermented dairy products. Such tanks are typically equipped with heat exchanging means, for example with a double jacket allowing transport of heating or cooling fluids. One can use for example tanks that are appropriate for fermentation.

Summary

In one embodiment the present invention provides baked cream-based sour cream production method involving purification of original raw milk from mechanical impurities using centrifuge milk purifiers or filtering materials, separation into heavy cream and skimmed milk , standardization of heavy cream through blending of heavy cream and skimmed milk, introduction of lactase enzyme into standardized cream, hydrohzation, homogenization at a temperature of 60 -75 °C and pressure of 13.0 - 15.0 MPa, pasteurization and baking of cream at a temperature of 95 - 97 °C for 2 - 4 hours, cooling down to a temperature of 8 - 10 °C, standardization in terms of protein weight ratio by adding dry skimmed milk or milk protein at least 2.0%, homogenization, pasteurization, time-temperature treatment for 5 minutes, cooling down to a fermentation temperature of 28 - 35 °C, introduction of the ferment consisting of lactococcus or a mixture of lactococcus and streptococcus thermophilics, stirring / agitation of the fermented mixture for at least 15 minutes and ripening until a curd is formed.

It is particularly preferred that the curd is formed in a tank. In one embodiment the standardized cream is hydrolyzed at a temperature of 4 - 6 °C for 12 hours. In an alternative embodiment the standardized cream is hydrolyzed at a temperature of 38 - 40 °C for 2 hours.

In a further embodiment the method comprises the following stages: conditioning of the received original raw milk consisting in purification and cooling using centrifuge milk purifiers or filtering materials (1), separation into heavy cream and skimmed milk (2), standardization of obtained cream in terms of fat weight fraction through blending of heavy cream and skimmed milk (3), introduction of lactase enzyme preparation (4), hydrohzation of standardized cream by time-temperature treatment and continuous agitation / stirring (5), homogenization of hydrolyzed cream and pasteurization at a temperature of 95 - 97 °C (6), 2 - 4 hours time-temperature treatment until it is a distinctly colored cream (7), cooling down to a temperature of 8 - 10 °C (8) and standardization in terms of protein weight fraction by introduction of dry skimmed milk or milk protein (9),

homogenization, pasteurization, and cooling down to fermentation temperature (10), ferment introduction (1 1) and agitation / stirring (12), ripening until a curd is formed (13), stirring / agitation (14) and cooling down of the curd (15).

After that the product should be bottled, packaged and labeled (16). After packaging and labeling, the fermented mixture should be cooled down in refrigerating chambers to a temperature of (4 ± 2) °C. Product maturation takes place parallel to the cooling down (17).

The diagram shows the baked cream-based sour cream production process flow.

1- Acceptance and conditioning of raw milk;

2- Milk separation;

3- Cream standardization;

4- Introduction of lactase enzyme preparation;

5- Hydrolization of standardized cream;

6- Cream homogenization and pasteurization;

7- Baking of hydro lyzed standardized cream;

8- Cooling down of standardized baked cream;

9- Introduction of dry component into baked cream;

10- Homogenization, pasteurization, cooling down of cream to fermentation temperature;

1 1- Introduction of ferment, cream fermentation;

12- Cream stirring / agitation;

13- Cream ripening;

14- Stirring / agitation of the formed curd;

15- Cooling down of the curd;

16- Bottling, packaging, and labeling;

17- Additional cooling down and maturation;

The invention will be further illustrated by the following non-limiting Figures and Example. Example 1

Preparation of a "baked sour-cream" type product.

A fermented cream product was prepared by the method of the invention. i) Preparation of milk-composition

The milk composition for preparing the sour-cream type product in this Example consisted of raw cow's milk obtained locally in liquid form. The raw milk (naturally containing about 3.5% by weight of fat) was purified by filtration and chilled to about 4°C by plate cooler for storage. The raw milk was heated to 55°C and fractionated to provide a milk composition having 15% fat, 2.7% protein, 4.1% lactose by weight respectively as well as an acidity content of about 15°T and pH 6.6. ii) Lactase treatment

Hydrolysis of the milk composition was then carried out by addition of lactase under continuous agitation. The lactase used was NOLA Fit55005L (commercially available from Chr. Hansen).

Hydrolysis was carried out to provide a hydrolysed milk composition having less than 1.5% lactose. The hydrolysed milk composition was then homogenized (13-15 MPa at 60-75 °C) and heat-treated at 95°C for 5 minutes. iii) Heat treatment ("Baking")

The milk composition was then heat-treated at a temperature of about 94°C for over 2 hours to provide a milk composition having a visually perceptible light golden brown "baked" shade comparable to NCS S 0510-Y40R and no darker than NCS S 1015-Y40R . The milk composition was then cooled to about 8°C. and then supplemented with milk protein 852 B from Ingredia to a protein content of about 3.5%. Homogenization and pasteurization were then repeated as described above before cooling. iv) Fermentation The ferment used was XPL-40 10x500U (commercially available from Chr. Hansen) which is a mixture of Lactococcus lactis subsp. Cremoris, Lactococcus lactis subsp. Lactis and Streptoccocus

thermophilus. The ferment was inoculated in the baked milk composition and dispersed by mixing for 30 minutes. Fermentation was carried out at 32 °C for about 9hours until pH 4.65 was reached, acidity was 65°T. The fermented milk composition was packaged and stored at 4°C. Product evaluation

Product characteristics 1 day after packaging were 15% fat, 3.5% protein and an acidity content of about 70°T and pH 4.4. Product viscosity measured using Rheomat 180 (mobile 22, speed 45, value at 15 sec, temp 10°C) was approximately 1500 and colour was comparable to 10-10-Y 40R.

Product appearance was characterized by a glossy surface, homogenous thick smooth mass, uniform beige colour throughout the mass. The taste profile included characteristic sour-cream as well as baked and slightly sweet notes.

Product shelf-life is at least 30 days under refrigerated conditions.

Example 2

Fermented milk products were prepared by the method of the invention as described above, using milk compositions having fat contents of 10%, 15%, 20% and 25% respectively and confirmed the suitability of the invention to prepare sour-cream type products having a fat content of 10%-40% by weight.

Sensory indicators of the products obtained are given in Table 1.

Physical and chemical parameters Table 2.

Claims

1. A method for the preparation of a fermented milk product comprising the following steps i) providing a milk composition comprising at least 5% by weight fat

ii) treating the milk composition by means of lactase to provide a milk composition having 3% or less by weight lactose

iii) heat treating the milk composition for at least 2 hours at a temperature of at least 90°C iv) fermenting the milk composition by means of lactic acid bacteria to provide a fermented product.

2. The method according to claim 1 wherein the milk composition of i) comprises at least 10%, 15%, 20%, 25%, 30%, 35% or 40% by weight fat.

3. The method according to any preceding claim wherein the lactase treatment ii) provides a milk composition having a lactose content of 2%, 1.5%, 1%, 0.5%, 0.2% or 0.1% or less by weight.

4. The method according to any preceding claim wherein the heat treatment iii) is carried out for 2-4 hours.

5. The method according to any preceding claim wherein the heat treatment iii) is carried out at a temperature of 92°C to 96°C.

6. The method according to any preceding claim wherein the lactic acid bacteria iv) are L. lactis and/or S. thermophilic.

7. A fermented milk product comprising:

i) at least 5% fat by weight,

ii) 3% or less lactose by weight

iii) at least 3% protein by weight

wherein said composition has a pH of less than 5 and a viscosity of at least 1 ,000 mPa.

8. The fermented milk product according to claim 7 having a viscosity of at least 1,250 mPa.

9. The fermented milk product according to any preceding claim comprising at least 10%, 15%, 20%, 25%, 30%, 35% or 40% fat by weight.

10. The fermented milk product according to any preceding claim comprising 2%, 1.5%, 1%, 0.5%, 0.2% or 0.1% or less by weight lactose.