WO2019068722A1

WO2019068722A1 - An alternative dairy product comprising vegetable oil and a method of producing the same

Info

Publication number: WO2019068722A1
Application number: PCT/EP2018/076813
Authority: WO
Inventors: Emmanouil Domazakis; Konstantinos Domazakis; Thomas MOSCHAKIS
Original assignee: Novaplot Enterprises Ltd
Priority date: 2017-10-03
Filing date: 2018-10-02
Publication date: 2019-04-11
Also published as: GR20170100447A; GR1009671B

Abstract

The present invention concerns a method for production of an alternative dairy product, using vegetable oil to substitute at least part of the dairy fat. Further, methods for producing an oil-dairy fat composite and an emulsion are disclosed. Furthermore, the present invention discloses an oil-dairy fat composite, an emulsion and alternative dairy product, comprising vegetable oil.

Description

An alternative dairy product comprising vegetable oil and a method of producing the same

FIELD OF THE INVENTION

The present invention concerns a method of production of an alternative dairy product, using vegetable oil to substitute at least part of the dairy fat. Further, methods for producing an oil-dairy fat composite and an emulsion are disclosed. Finally, the present invention discloses an oil-dairy fat composite, an emulsion and alternative dairy product, comprising vegetable oil.

BACKGROUND OF THE INVENTION

The negative health effects correlated with the increased intake of dairy fat, have driven research towards the development of low-fat cheeses. Nevertheless, dairy fat has a main role in sensory and textural properties of the dairy products. As a result, fat reduction in dairy products, such as cheese, may result in poor meltability, rubbery texture and bitterness.

Some vegetable oils have been used in the making of dairy products, to fully or partially replace the milk fat. High-melting vegetable fats, such as palm oil, or modified vegetable oils subjected to interesterification or hydrogenation, have been mainly used for that purpose.

Replacing the fat content of dairy products with vegetable oils with a low saturated fat content, contributes to a healthier saturated/unsaturated fatty acid balance, yet the resulting products are prone to oiling off phenomena and to textural and sensory defects, such as soft texture in hard cheeses, off-flavors etc. Researchers have thus commonly used appropriate emulsifiers and/or stabilizers, to ensure stable oil incorporation.

For example, EP 0 368492 teaches a method for preparing a cheese product having a low level of saturated fat and cholesterol. The invention makes use of a vegetable fat- based cream added to skim, semi-skimmed or low fat milk, transferred into a cheese vat and processed using conventional techniques to form cheese. The said vegetable fat-based cream is prepared by adding a blend of pasteurized vegetable oils, such as soya and/or coconut oil and hydrogenated soya and/or coconut oil and an emulsifier to an aqueous phase comprising a pasteurized blend of water and a stabilizer, such as gelatin. In one embodiment of the invention the vegetable fat comprises a blend of vegetable fats, which has a similar melting point profile to milk fat over the range of 5° C to 38º C.

Another example of a low cholesterol dairy product may be produced according to US 5063074. Its disclosure relates to the combination of skim milk with a pre-mix comprising a vegetable oil carrier as well as agents, which impart texture and flavoring properties to the milk product. The resultant fluid milk product can be pasteurized and stored at refrigerated temperatures for at least six weeks, or it can be used to produce a number of dairy products, including hard cheese. In representative formulations, which are disclosed in US 5063074, the premix is comprised of vegetable oil, emulsifiers, gums and flavoring agents.

WO 2011/070114 relates to a method for the production of a milk-based alternative product, in particular a cheese alternative product, an ice cream alternative product, a custard alternative product or a chilled or frozen dessert alternative product, using an edible oil to substitute at least part of the milk fat. The method comprises the steps of a) providing edible oil at a temperature of about 50 to 55º C, b) providing milk at about 2.3 bar, with a flow rate of about 10 to 12 tons/h, at about 55º C, c) inserting the oil at about 2.5 bar, with a flow rate of about 500 to 2000 liters/h, into the milk, to obtain a mixture and d) subjecting the mixture to mild homogenization at about 10 bar. The resulting products are characterized by good stability; however, implementation of the method requires the setting of a particular pipe system, which introduces a certain complexity to the implementation of the method.

US 4425370 teaches a process for producing a margarine-type food product including the steps of: blending a dairy substance such as skim milk with a hydrogenated vegetable oil at a ratio of approximately 60/40 ratio; processing the skim milk/oil mixture through a homogenizer to obtain an oil globule size range essentially similar to a fat globule size range found in dairy cream; blending a dairy cream with the homogenized skim milk/oil mixture; and processing the mixture of dairy cream and skim milk/oil through a butter churning process. A primary objective of the present invention is to provide a method for the production of an emulsion, comprising a vegetable oil preferably containing more than 50% of unsaturated fatty acids, said emulsion being characterized by excellent stability in terms of vegetable oil incorporation. Another object of the present invention is to provide a method for the production of an alternative dairy product, which may be easily implemented by dairy plants, without the need of special equipment. Finally, the present invention aims to provide an oil-dairy composite, an emulsion and an alternative dairy product resulting thereof, said product being characterized by superior stability in terms of vegetable oil incorporation compared to prior art methods, and desired organoleptic properties.

One object of the present invention is met by a method of preparing an oil-dairy fat composite, comprising vegetable oil and a milk fat preparation. Said composite may be used in the preparation of an emulsion to be further used in the making of a dairy or dairy-type alternative product. By the use of said composite, oiling-off phenomena in the final dairy products are virtually absent, while organoleptic properties are similar to the traditional products. In addition, due to the excellent vegetable oil incorporation, improved product yields are obtained in the final product. SUMMARY OF THE INVENTION

The present invention aims at the production of dairy alternative products, wherein at least a part of the milk fat has been substituted with a vegetable oil, said vegetable oil having an unsaturated fatty acid content preferably of more than 40%, more preferably more than 50% and most preferably more than 60% of unsaturated fatty acids. The milk fat substitution with a vegetable oil is in the range from 0.5% to 99-5%, preferably from 10% to 90%.

In the context of the present invention, the terms "dairy product", "dairy alternative product" and "dairy-type product", whenever used herein, are used interchangeably and refer to dairy alternative products, in which at least part of the dairy fat has been substituted by vegetable oil. The above terms, as herein used, include products comprising milk proteins, preferably comprising milk. In particular, the terms "dairy product", "dairy alternative product" and "dairy-type product", include products selected from the group comprising dairy drinks, fermented and non-fermented dairy products (e.g. cheeses of all types, yogurt etc.), ice cream products and chilled or frozen dairy desserts. The term "dairy product", "dairy alternative product" and "dairy-type product", particularly also includes aerated products, in particular whipping cream.

According to the invention a vegetable oil is used. The vegetable oil can be any edible vegetable oil fit for human consumption or mixtures thereof. Preferably, from a dietary point of view the selected vegetable oil is essentially an unsaturated oil, containing more than 40% of unsaturated fatty acids, preferably more than 50% and more preferably more than 60% of unsaturated fatty acids (as determined by a Fatty Acid Methyl Ester analysis). According to a further preferred embodiment, the selected oil or oils are not subjected to any treatment for modifying the initial distribution of fatty acids or the degree of their saturation, by processes like interesterification or hydrogenation. Edible vegetable oils that can be used according to the present invention, without being restricted thereto, include: olive oil, soybean oil, canola oil, pumpkin seed oil, corn oil, rapeseed oil, sunflower oil, safflower oil, peanut oil, walnut oil, sesame oil, wheat germ oil, grape seed oil, argan oil, rice bran oil, and mixtures thereof. Many other kinds of oils that are used for cooking, or any other food uses, can, however, also be used, such as almond oil and avocado oil. From the oils mentioned above, olive oil, sunflower oil, corn oil, soybean oil, canola oil and mixtures thereof are especially preferred, with olive oil being the most preferred oil. According to yet another preferred embodiment, the vegetable oil has not been pre-emulsified or otherwise combined with an added emulsifier before its combination with the milk fat preparation.

The milk fat preparation, as referred to in the present invention, is a preparation containing milk fat of from 1 to 100% (w/w), preferably of from 15 to 80%, more preferably of from 15 to 70%, even more preferably of from 15 to 60%, yet more preferably of from 20 to 50% and most preferably of from 30 to 50% (w/w). The milk fat preparation may comprise a percentage of milk proteins in the range from 0.1 % to 3.5% (w/w), preferably of from 0.1 to 2.8% (w/w), more preferably of from 0.1% to 2.5% (w/w) and most preferably of from 0.1 to 0.7% (w/w). In another embodiment, the milk fat preparation comprises substantially no milk proteins, in particular no milk proteins. The milk fat preparation can be considered to be an emulsion. In the present invention, the milk fat preparation will be further distinguished as a milk fat preparation (a) and a milk fat preparation (b).

According to the present invention, the milk fat preparation (a) is a milk cream, derivable from the processing of milk, by the separation of milk fat from the raw milk. Preferably, the milk fat preparation (a) contains milk fat of from 10 to 80%, in particular of from 15 to 60%, more preferably of from 20 to 50% and most preferably of from 30 to 50% (w/w). After separation of milk fat from the raw milk, which is conventionally carried out by using a centrifugal device, the milk is separated into low-fat milk (e.g. skimmed milk) and fat/cream. The milk fat/cream can then be used to standardize the milk's fat content, or can be pasteurized or UHT treated or further used for the making of related products, such as creme fraiche, coffee cream, cooking cream, sour cream etc. As per a most preferred aspect, the milk fat preparation (a) is a manufacturing milk cream, containing approximately of from 30 to 50% (w/w) fat, preferably approximately 40% (w/w) fat. The milk fat preparation (a), may be pasteurized or non-pasteurized, preferably non-pasteurized. The oil- dairy composite produced using the milk fat preparation (a) is herein defined as oil- dairy composite (a). Similarly, the emulsion derivable from the oil-dairy composite (a) is herein defined as emulsion (a).

The milk fat preparation (b), as referred to in the present invention and further explained below, derives from an additional treatment of the milk fat preparation, prior to its use according to the present invention. Said additional treatment, comprises fat crystallization and a subsequent mechanical treatment, comprising at least mixing or shearing. Preferably, the milk fat preparation (b) derives from the, as above defined, additional treatment of the milk fat preparation (a). The oil-dairy composite produced using the milk fat preparation (b) is herein defined as oil-dairy composite (b). Similarly, the emulsion derivable from the oil-dairy composite (b) is herein defined as emulsion (b).

It is to be noted that the presence of the milk fat globule membrane (MFGM) is imperative for obtaining the technical effect of vegetable oil incorporation in the herein disclosed milk-based systems. According to the present invention, it is preferred that the milk fat globule membrane (MFGM) which is inherently contained in the milk fat preparation (a) and (b), acts as an interface membrane for aiding the combination of milk fat and vegetable oil within the same emulsion droplet.

All percentages defined herein refer to weight, unless otherwise indicated.

The present invention provides a method for producing an oil-dairy fat composite (Embodiment 1) comprising the steps of:

1) Providing a vegetable oil, 2) Providing a milk fat preparation,

3) Combining the vegetable oil and the milk fat preparation into a mixture and subjecting said mixture to a homogenization (a) to form the oil-dairy fat composite.

In a preferred embodiment, milk fat preparation (a) is used, resulting in the oil-dairy fat composite (a). In another preferred embodiment, milk fat preparation (b) is used, resulting in the oil-dairy fat composite (b). The present invention also provides an oil-dairy fat composite obtainable by the method according to Embodiment l. Further provided are an oil-dairy fat composite (a) and an oil-dairy fat composite (b).

The present invention further provides a method for producing an emulsion (a), as Embodiment 2, and a method for producing a product derivable thereof, as an Embodiment 3.

In an embodiment, Embodiment 2, for the production of an emulsion (a) which contains vegetable oil, the method comprises the steps of:

1) Providing a vegetable oil,

2) Providing a milk fat preparation (a),

3) Combining the vegetable oil and the milk fat preparation (a) into a mixture and subjecting said mixture to a homogenization (a) to form an oil- dairy fat composite (a),

4) Blending the oil-dairy fat composite (a) with a milk protein composition (i) and processing said mixture by a homogenization step (b), to obtain an emulsion (a).

The present invention further provides a method for producing a dairy-type product (Embodiment 3), the method comprising the steps of:

1) Providing a vegetable oil,

2) Providing a milk fat preparation (a),

4) Blending the oil-dairy fat composite (a) with a milk protein composition (i) and processing said mixture by a homogenization step (b), to obtain an emulsion (a), 5) Blending emulsion (a) with a milk protein preparation (ii) and further processing to obtain a dairy product.

The present invention also provides an emulsion (a) and a dairy product obtainable by a method according to the above Embodiments 2 and 3, respectively.

The present invention further provides a method for producing an emulsion (b), as Embodiment 4, and a method for producing a product derivable thereof, as an Embodiment 5.

The method of Embodiment 4 for the production of emulsion (b), comprises the steps of:

1) Providing a vegetable oil,

2) Providing a milk fat preparation (b),

3) Combining the vegetable oil and the milk fat preparation (b) into a mixture and subjecting said mixture to a homogenization (a) to form an oil- dairy fat composite (b),

4) Blending the oil-dairy fat composite (b) with a milk protein composition (i), and optionally processing said mixture by a homogenization step (b), to obtain an emulsion (b).

The present invention further provides a method for producing a dairy-type product (Embodiment 5), the method comprises the steps of:

1) Providing a vegetable oil,

2) Providing a milk fat preparation (b),

4) Blending the oil-dairy fat composite (b) with a milk protein composition (i) and optionally processing said mixture by a homogenization step (b), to obtain an emulsion (b),

5) Blending emulsion (b) with a milk protein preparation (ii) and further processing to obtain a dairy product. The present invention also relates to an emulsion (b) and a dairy-type product, obtainable by a method according to the above Embodiments 4 and 5, respectively. The present invention further relates to a method for the production of an alternative oU-dairy composite, which contains vegetable oil (Embodiment 6), said method comprising the steps of:

1) Providing a vegetable oil,

2) Providing a milk protein composition (i),

3) Providing a milk fat preparation,

4) Combining the vegetable oil, the milk fat preparation and the milk protein composition (i) into a mixture and processing said mixture by homogenization, to obtain the alternative oil-dairy fat composite.

In addition, the present invention provides a method for producing a dairy-type product (Embodiment 7), using the alternative oil-dairy composite of Embodiment 6, said method comprising the steps of:

1) Providing a vegetable oil,

2) Providing a milk protein composition (i),

3) Providing a milk fat preparation,

4) Combining the vegetable oil, the milk fat preparation and the milk protein composition (i) into a mixture and processing said mixture by homogenization, to obtain the alternative oil-dairy composite,

5) Blending the alternative oil-dairy composite with a milk protein preparation (ii) and further processing to obtain a dairy product.

The present invention also refers to an alternative oil-dairy fat composite and a dairy- type product, obtainable by a method according to the above Embodiments 6 and 7.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION Embodiment 1: According to Embodiment 1 of the invention, an oil-dairy fat composite is prepared. Step (1) comprises the use of a vegetable oil. Step (2) comprises the use of a milk fat preparation.

Step (3) of Embodiment 1 comprises combining the vegetable oil and the milk fat preparation, preferably in a suitable container, and subjecting said combination to a homogenization (a). Homogenization (a) preferably refers to a mild homogenization step and may comprise mixing and/or dispersing, and/or shearing and/or homogenizing to obtain a homogeneous mixture of dairy fat and oil. For example, the mixing may be carried out by conventional means of mixing or by using a two- stage pressure homogenizer. Preferably, homogenization (a) is carried out by a dispersing device (e.g. Ultra-Turrax^®, Silverson^®) or an ultrasonic homogenizer.

According to a preferred aspect, the vegetable oil is at a temperature of from 5 to 65 °C, preferably at a temperature of from 30 to 60 °C and more preferably of from 40 to 60 °C, when combined with the milk fat preparation. Preferably, the milk fat preparation is at a temperature between 40 to 65 °C, preferably between 45 to 60 °C and more preferably between 50 to 60 °C, when combined with the vegetable oil. Preferably, the raising of the temperature of the milk fat preparation to the above disclosed levels occurs under continuous mixing. Thus, homogenization (a) is conducted at a temperature between 5 to 65 °C, preferably between 10 to 65 °C and more preferably between 40 to 60 °C.

It is preferred that the homogenization step (a) results in an average droplet size of no more than 20 μm. Preferably, using the homogenization step (a), an average droplet size of 2 to 15 μm is obtained, more preferably of 2 to 10 μm, even more preferably of 2 to 6 μιη and most preferably of 3 to 4 μιη. The amounts of the vegetable oil and the milk fat preparation to be used, depend on the fat content of the milk fat preparation, the intended ratio of oil : milk fat in the oil-dairy fat composite and the intended fat content in the final product. Following completion of step (3), the oil-dairy fat composite can be used as such or/and may be used in further processing, e.g. for the production of emulsions.

In the context of the present invention, the average droplet size or average emulsion droplet size can be referred to the Sauter mean diameter D[3,2] and can be measured by laser diffraction techniques, for example by using a Malvern instrument (e.g. Mastersizer 2000).

In a preferred embodiment of the invention, no additional emulsifiers and/or no stabilizers, in particular no additional emulsifier, is used in the method of Embodiment 1. Embodiment 2: The present invention further provides a method for the production of an emulsion (a), which comprises the use of a milk fat preparation (a) for obtaining the oil-dairy fat composite (a), by a method as described in Embodiment 1; the blending of said oil-dairy fat composite (a) with a milk protein composition (i) and; the processing of said mixture by a homogenization step (b). The present invention also provides an emulsion (a), derivable from a process according to Embodiment 2. In a preferred embodiment of the invention, the emulsion (a) itself is a dairy-type product. The present invention further provides a dairy-type product obtainable according to Embodiment 2.

The milk fat preparation (a) is a milk cream, containing milk fat preferably of from 10 to 8o%, in particular of from 15 to 60%, more preferably of from 20 to 50% and most preferably of from 30 to 50% (w/w). The milk protein composition (i) is essentially an aqueous dispersion comprising milk proteins (e.g. caseins, whey proteins). The milk protein composition (i) may further comprise milk fat. Its milk fat content may range from 0.01% up to 14%, preferably from 0.01% up to 9% and most preferably from 0.1% up to 596 (w/w). In another embodiment, the milk protein composition comprises substantially no milk fat, in particular no milk fat. As per a preferred aspect, the milk protein composition (i) further comprises solids, lactose and minerals. According to the most preferred embodiment, the milk protein composition (i) is milk. Preferably, the milk is obtained from cow, goat, sheep, buffalo or any other origin used in food production. Nevertheless, it can also be a mixture of milks of different origin. Consequently, the milk protein composition may be skimmed milk, semi-sMmmed milk or whole milk. Preferably, however, the milk protein composition is a skimmed milk. In yet another preferred embodiment, the milk may be partly or wholly replaced by a recombined milk powder. Preferably, the milk protein composition (i) contains a protein content of from 1% to 6.5% (w/w), preferably from 3% to 6.5%, and most preferably from 3% up to 5% (w/w).

The oil-dairy fat composite (a) is combined with a milk protein composition (i) and said mixture is subjected to a homogenization step (b) to form an emulsion (a). The emulsion (a) components, i.e. oil-dairy fat composite (a) and milk protein composition (i) are at a temperature between 5 to 65 °C, preferably between 10 to 65 °C and more preferably between 40 to 60 °C, when combined. Thus, the homogenization step (b) is conducted at a temperature range between 5 to 65 °C, preferably between 10 to 65 °C and more preferably between 40 to 60 °C.

Homogenization (b) may be conducted by a high pressure homogenizer, wherein a pressure between about 10 and 250 bar, preferably between 10 and 100 bar and more preferably between 10 and 50 bar is used. Nevertheless, other means of homogenization (e.g. mixing or dispersing or shearing) may be used alone or in combination with the high pressure homogenization. According to a preferred embodiment, the homogenization step (b) results in an average droplet size of no more than 20 μm. Preferably, using the homogenization step (b), an average droplet size of 1 to 15 μm is obtained, more preferably of 2 to 10 μιη, even more preferably of 2 to 6 μm and most preferably of 2 to 4 μm. It is particularly noted that the average droplet size following the homogenization step (a) is always higher than the average droplet size following homogenization step (b). Thus, according to a preferred aspect, the average droplet size following homogenization (a) is between 2 to 20 μm, preferably between 1 to 10 μm and more preferably between 3 to 4 μm, while the average droplet size following homogenization (b) is from 1 to 10 μm, more preferably of from 2 to 6 μm and most preferably of from 2 to 4 μm. For example, if the homogenization step (b) is conducted by the use of a two-valve homogenizer at 35 bar, then the homogenization step (a) should result in an effect on the average droplet size, equivalent to the effect obtained by the use of a two valve-homogenizer at a pressure equal to≤ 35 bar.

The products of homogenization (a) and (b) in this embodiment are micro- structurally different, as they are produced from different sets of raw materials.

The milk fat preparation (a), the oil and the milk protein composition (i) participate in the emulsion in such amounts that the total amount of fat in said emulsion does not exceed 35% (w/w), preferably does not exceed 25 96 (w/w) and more preferably does not exceed 20 % (w/w).

According to a preferred embodiment, no added emulsifier is used in the method of Embodiment 2. More preferably, no added stabilizer is used in the method of Embodiment 2.

Following the completion of the homogenization step (b), the emulsion (a) can be used as such or/and may be used in further processing for e.g. the production of a dairy product. Further processing of the emulsion (a) comprises the process steps appropriate for the production of each product type, as known in the art. For example, further processing may include pasteurization, cooling, whipping, curd formation (e.g. by inoculation of starter cultures and/or rennet addition), incubation steps, stretching step, cheddaring step, addition of stabilizers, addition of thickeners, addition of flavor ingredients, packaging, storage etc.

Embodiments: According to a yet preferred aspect (Embodiment 3), the present invention further comprises blending of emulsion (a) with a milk protein composition (ii), to obtain a dairy-type product. The present invention also comprises a dairy-type product obtainable by a method according to Embodiment 3. The milk protein composition (ii) is essentially an aqueous dispersion comprising milk proteins (e.g. caseins, whey proteins). The milk protein composition (ii) may further comprise milk fat. Its milk fat content may range from 0.01% up to 14%, preferably from 0.01% up to 9% and most preferably from 0.1% up to 5% (w/w). According to a preferred embodiment, the milk protein composition (ii) is milk. Preferably the milk is obtained from cow, goat, sheep, buffalo, or any other origin used in food production. Nevertheless, it can also be a mixture of milks of different origin. Consequently, the milk protein composition may be skimmed milk, semi- skimmed milk or whole milk. Preferably, however, the milk protein composition (ii) is a skimmed milk It is preferred that the milk protein composition (ii) has the same composition as the milk protein composition (i). For example, the milk protein preparations (i) and (ii) may be skimmed milk. Preferably, the milk protein composition (ii) contains a protein content of from 1% to 6.5% (w/w), preferably from 3% to 6.5%, and most preferably from 3% up to 5% (w/w). Blending of the emulsion (a) with the milk protein composition (ii) may conventionally take place in the cheese tank under conditions of gentle mixing with the purpose to provide a homogeneous mixture.

Further processing of the blend comprising emulsion (a) and milk protein composition (ii), comprises the process steps appropriate for the production of each product type, as known in the art. For example, further processing may include pasteurization, cooling, curd formation (e.g. by inoculation of starter cultures and/or rennet addition), incubation steps, whipping, stretching step, cheddaring step, addition of stabilizers, addition of thickeners, addition of flavor ingredients, packaging, storage etc. Embodiment A:

The present invention further provides a method for the production of an emulsion (b), which comprises the use of a milk fat preparation (b) for obtaining the oil-dairy fat composite (b), by a method as described in Embodiment ι; the blending of said oil-dairy fat composite (b) with a milk protein composition (i) and optionally the processing of said mixture by a further homogenization step (b). The present invention also provides an emulsion (b), derivable from a process according to Embodiment 4. In a preferred embodiment of the invention, the emulsion (b) itself is a dairy-type product The present invention further provides a dairy-type product obtainable according to Embodiment 4.

According to this embodiment, the milk fat preparation (b) is produced from the milk fat preparation when the latter is subjected to an additional treatment. According to this embodiment, the milk fat preparation is subjected to an additional treatment step, prior to its combination with the vegetable oil as per the Embodiment 1. Preferably, the milk fat preparation (b) is derived from the milk fat preparation (a), when the latter is subjected to the additional treatment.

Said additional treatment step comprises two steps, namely the fat crystallization step (step 2a) and the mechanical processing step (step 2b). The mechanical processing step always follows the fat crystallization step, i.e. it is subsequent to the fat crystallization step.

Fat crystallization (step 2a) is a known process that can be routinely conducted by any method known to the person skilled in the art. Preferably, the fat crystallization of step 2a, is a process achieved at least by cooling below a temperature threshold, leading to nucleation and subsequent crystal growth. As per a preferred aspect of the present invention, the milk fat crystallization is achieved by cooling down the milk fat preparation to a temperature range between 8 °C to -18 °C, preferably between 8 °C to -10 °C, more preferably between 6 °C to -5 °C and most preferably to a temperature between 6 °C to o °C for suitable periods of time, which depend from factors such as the saturated fat content of the milk fat preparation . Due to the crystal growth and, subsequently, the formation of a fat crystal network, the solidification of the milk fat is accomplished. For example, the fat crystallization process may be carried out by cooling the milk fat preparation to a temperature of 4 °C, for a period of at least 10 hours, for example 24 hours. Fat crystallization may however also be achieved by applying different conditions of temperature and cooling times, known to the person skilled in the art.

The mechanical processing (step 2b) is carried out preferably by shearing or mixing of the milk fat preparation of step 2a, at temperatures between 10 to 40 °C, preferably between 15 to 30 °C and more preferably between 15 to 20 °C, until aggregates (clusters) of fat globules are formed.

According to a most preferred aspect, milk fat preparation (b) is further subjected to a centrifugation step, such that a layer of liquid milk fat is formed on the surface of the milk fat preparation (b). Subsequently, the formed layer of liquid fat is at least partially removed, prior to the combination with the vegetable oil. For example, the milk fat preparation (b) may be centrifuged at 8ooog for 10 min. Using said most preferred aspect, the homogenization (b) may not be required for the production of product types wherein high pressure homogenization is traditionally not used. For example, products for the production of which homogenization is conventionally not used are traditional cheeses of hard, semi-hard and semi-soft type (such as Gouda, Feta, Camembert etc.). Homogenization is optional in the production of traditional cream and yoghurt. Step (3) of Embodiment 4, comprises combining the vegetable oil and the milk fat preparation (b), preferably in a suitable container, and subjecting said combination to a homogenization (a).

According to a preferred aspect, the temperature of the vegetable oil and of the milk fat preparation (b) at the combination thereof (step 3), is as disclosed in Embodiment 1. Preferably, the raising of the temperature of the milk fat preparation (b) to the above disclosed levels occurs under continuous mixing.

Homogenization (a) preferably refers to a mild homogenization step and may comprise mixing and/or dispersing and/or shearing and/ or homogenizing to obtain a homogeneous mixture of dairy fat and oil. Mixing may be carried out by conventional means of mixing or by using a two-stage pressure homogenizer. Preferably, homogenization (a) is carried out by a dispersing device (e.g. Ultra- Turrax^®, Silverson^®) or an ultrasonic homogenizer.

It is preferred that the homogenization step (a) results in an average droplet size of no more than 20 μm. Preferably, using the homogenization step (a), an average droplet size of 2 to 15 μm is obtained, more preferably of 2 to 10 μm, even more preferably of 2 to 6 μm and most preferably of 3 to 4 μm. The amounts of the above ingredients to be used, depend on the fat content of the milk fat preparation (b), the intended ratio of oil : milk fat in the oil-dairy fat composite (b) and the intended fat content in the final product.

In step (4), the oil-dairy fat composite (b) is blended with a milk protein composition (i), and said mixture is optionally processed by a further homogenization step (b) to obtain emulsion (b).

The milk protein composition (i) is as set forth above in Embodiment 2.

The components of emulsion (b), i.e. the oil-dairy fat composite (b) and milk protein composition (i) are at a temperature between 5 to 65 °C, preferably between 30 to 62 °C and more preferably between 40 to 60 °C, when combined. Homogenization (b), whenever conducted, is performed as described above in Embodiment 2. The products of homogenization (a) and (b) in this Embodiment are micro-structurally different, as they are produced from different sets of raw materials. The milk fat preparation (b), the oil and the milk protein composition (i) participate in the emulsion (b) in such amounts that the total amount of fat in said emulsion does not exceed the 50% (w/w), preferably does not exceed the 30 % (w/w) and more preferably does not exceed the 20 % (w/w). Emulsion (b) can be used as such or/and may be used in further processing e.g. for the production of dairy products. The further processing steps for the emulsion (b) are as set forth above in Embodiment 2. The present invention also provides an emulsion (b), derivable from a process according to Embodiment 4. The use of added emulsifiers or emulsifying agents is possible but not compulsory. According to a preferred embodiment, no added emulsifier is used in the method of Embodiment 4. More preferably, no added stabilizer is used in the method of Embodiment 4.

Embodiment s;

According to Embodiment 5, the present invention further comprises blending of emulsion (b), as obtained by Embodiment 4, with a milk protein composition (ii), to obtain a dairy-type product. The present invention also comprises a dairy-type product obtainable according to Embodiment 5.

The milk protein composition (ii) is as set forth above in Embodiment 3.

Blending of the emulsion (b) with the milk protein composition (ii) may conventionally take place in the cheese tank under conditions of gentle mixing with the purpose to provide a homogeneous mixture.

Further processing of the blend comprising emulsion (b) and the milk protein composition (ii), is as described above in Embodiment 3 for the blend comprising emulsion (a).

Embodiment 6:

The present invention further pertains to a method for the production of an alternative oil-dairy fat composite. In addition, the present invention relates to an alternative oil-dairy fat composite, according to Embodiment 6. In a preferred embodiment of the invention, the alternative oil-dairy fat composite itself is a dairy- type product. The present invention further provides a dairy-type product obtainable according to Embodiment 6. The alternative oil-dairy fat composite is considered to be an emulsion. The alternative oil-dairy fat composite can thus be defined as an emulsion.

Step (4) comprises combining together the vegetable oil, the milk protein composition (i) and the milk fat preparation in a suitable container, and subjecting said combination into homogenization step, to obtain an alternative oil-dairy fat composite. Preferably, the homogenization step in Embodiment 6 is a homogenization (b). According to a preferred embodiment, the milk fat preparation of Embodiment 6, is a milk fat preparation (b). The milk protein composition (i) and the milk fat preparation, are as described above in Embodiment 1. The homogenization steps (a) or (b) are as described above in Embodiments 1 and 2.

The use of added emulsifiers or emulsifying agents is possible but not compulsory. According to a preferred embodiment, no added emulsifier is used in the method of Embodiment 6. More preferably, no added stabilizer is used in the method of Embodiment 6.

Embodiment 7:

The present invention relates to a method for the production of a dairy-type product, wherein the alternative oil-dairy fat composite of Embodiment 6 is further blended with milk protein composition (ii). The invention also relates to a dairy-type product, as being produced from the blending of the alternative oil-dairy fat composite of Embodiment 6 with a milk protein composition (ii). Further, the present invention comprises a dairy-type product obtainable according to Embodiment 7. The present invention also provides emulsion (c) which is an intermediate product obtained by blending the alternative oil-dairy composite with a milk protein preparation (ii) according to Embodiment 7 in step 5).

The milk protein composition (ii) is as described above in Embodiment 3. Further processing of the blend comprising the alternative oil-dairy fat composite and the milk protein composition (ii), is as described above in Embodiment 3. Advantageously, the present invention enables the production of aerated products, such as whipping cream.

The invention will be further illustrated by Examples 1 and 2 without restricting it.

Example 1: Preparation of Gouda cheese containing olive oil, using different ways (protocols) of incorporating the olive oil. Three experimental batches were prepared using the same quantity of skimmed milk. Appropriate amounts of dairy cream (40% wt fat) and olive oil, were used accordingly. A first experiment was carried out (Batch 1) to provide the control samples. Experiment 1 made no use of olive oil, only dairy cream was used. Appropriate amounts of skimmed milk and dairy cream were combined and mildly stirred at 55 °C, to provide a milk having a total fat content of 3.0 wt% and a standardized protein to fat ratio of about 1.0 : 1.0. Homogenization then followed, using a two-stage homogenizer, at 50 bar and at 55 °C.

A second experiment was carried out according to the herein disclosed method (Batch 2). Appropriate amounts of olive oil and dairy cream (i.e. milk fat preparation) were combined and mildly stirred at 55 °C until a uniform dispersion was formed. Thus, the oil-dairy fat composite was obtained. Then, the skimmed milk, corresponding to the milk protein composition (i), was added and a homogenization step (a) followed using a dispersing device (e.g. an Ultra Turrax®, at 3000 rpm) to form a coarse emulsion (i.e. emulsion (a)). The resulting emulsion had a final fat content of 3.0 wt% (50% olive oil- 50% milk fat) and a standardized protein to fat ratio of about 1.0 : 1.0. It was then homogenized at 50 bar and at 55 °C.

The same materials and quantities thereof were used in a third experiment (Batch 3), with the difference that the amount of skimmed milk was homogenized with olive oil at 50 bar and then dairy cream was added and mildly mixed in the homogenized olive oil- sMmmed milk mixture. Likewise, the resulting mixture had a final fat content of 3.0 wt% and a standardized protein to fat ratio of about 1.0 : 1.0.

All the resulting compositions (Batches 1-3) were analyzed in terms of emulsion droplet size distribution, using a Mastersizer 2000 (Malvern Instruments) and the Sauter mean diameter (D [3, 2]) was calculated.

The experimental batches followed the process steps typical for the production of Gouda type cheeses. In specific, the batches 1-3 were pasteurized at 72 °C/i5 sec, cooled to 33 °C and pre-ripened for 30 min after culture addition. Then, the milk was 'renneted' for 40 min. The coagulum was cut and the curd was stirred for 15 min. After whey removal and washing, the curd was scalded to 36 °C and stirred for 15 min. Most of the whey was drained off, and the curd was pre-pressed under the remaining whey for 15 min. The curd was fitted into the molds and pressed with increasing pressure for 2 hrs. The obtained curd blocks were kept in cold brine until the following morning.

Table 1 shows a comparison of bulk whey fat (wt %) (measured by the Soxhlet method) derived during the further processing of the three experimental batches to deliver the Gouda type cheeses.

As shown above, Batch 2, which corresponds to the herein disclosed method resulted in lower D [3.2] and lower fat losses in the whey.

Example 2: Preparation of whipping cream (40% fat) containing olive oil, using different ways (protocols) of incorporating the olive oil.

Two experimental batches were prepared using the same quantity of skimmed milk, dairy cream (50% wt fat) and olive oil. A first experiment was carried out (Batch 1) to provide the control samples. In Experiment 1 skimmed milk was homogenized with olive oil (30% w/w) using an Ultra Turrax® at 25000 rpm at 55 °C. The obtained emulsion was combined with an appropriate quantity of dairy cream (60% wt fat) resulting in a final emulsion with a fat content of 40.0 wt% (50% olive oil - 50% milk fat). The final emulsion was stored at 4 °C overnight. Subsequently, air was intentionally beaten into the final emulsion using an electric beater and the froth appearance, whipping time and volume increase (overrun) were examined. No whipping cream was formed even after 5 min of whipping. A second experiment was carried out according to the herein disclosed method (Batch 2). Appropriate amounts of dairy cream (60% wt fat) were pre-treated, according to the present invention. In particular, the dairy cream was initially stored at 4 °C for overnight and subsequently was subjected to a high shearing mechanical process using an Ultra Turrax® at 3000 rpm at 15 °C for about 4 min, until aggregates of fat globules were formed. The so treated dairy cream was then centrifuged mildly at 8ooog for 10 min at 55 °C. A layer of liquid milk fat was, in this way, separated from the bulk of the treated dairy cream and then carefully removed.

The removed liquid milk fat was subsequently replaced by a suitable amount of vegetable oil.

The vegetable oil was at a temperature of 15 °C, while the treated dairy cream was brought at a temperature between 50 to 60 °C, under continuous mixing. The olive oil and the treated dairy cream were then combined to form a mixture. This mixture was homogenized using an Ultra Turrax® at 25000 rpm at 55 °C. The final emulsion had a fat content of 40.0% w/w (50% olive oil-50% milk fat)] and was stored at 4 °C overnight. Subsequently, air was intentionally beaten into the emulsion using an electric beater and the froth appearance, whipping time and volume increase (overrun), were examined. In this case, whipping cream was formed after two and a half minutes having an overrun of 60%.

As shown above, whipping cream was obtained using the method of the present invention, with an overrun of 60%. The method of the prior art (Batch 1) did not obtain the intended product.

Preferred embodiments of the invention are provided herewith:

1. Method for the production of an oil-dairy fat composite, which contains vegetable oil, comprising the steps of: i) Providing a vegetable oil,

ii) Providing a milk fat preparation,

iii) Combining the vegetable oil and the milk fat preparation into a mixture and subjecting said mixture to a homogenization (a) to form the oil-dairy fat composite. 2. Method for the production of an emulsion (a), which contains vegetable oil, and comprises the steps of: i) Providing a vegetable oil,

ϋ) Providing a milk fat preparation,

iii) Combining the vegetable oil and the milk fat preparation into a mixture and subjecting said mixture to a homogenization (a) to form an oil-dairy fat composite,

iv) blending the oil-dairy fat composite with a milk protein composition (i) and processing said mixture by a homogenization step (b) to obtain the emulsion (a). 3. Method according to any one of embodiments 1 to 2, wherein homogenization (a) is carried out by mixing, at a temperature in the range of from 10 to 62º C.

4. Method according to embodiment 2, wherein homogenization (b) is carried out at a pressure of 10 to 250 bar and at a temperature in the range of from 10 to 62º

C.

5. Method for the production of a dairy product, comprising preparing an emulsion (a) by the method according to any one of embodiments 2-4 and blending said emulsion with a milk protein composition (ii).

6. Method for the production of a dairy product, according to any of the above embodiments 2-5, wherein the milk protein composition (i) is an aqueous dispersion comprising milk proteins, preferably milk, more preferably skimmed milk.

7. Method for the production of a dairy product, according to embodiment 5, wherein the milk protein composition (ii) is an aqueous dispersion comprising milk proteins, preferably milk, more preferably skimmed milk. 8. The method of any of the preceding embodiments, wherein the vegetable oil is an unsaturated oil, preferably containing more than 40% of unsaturated fatty acids, more preferably more than 50%. 9. The method of any of the preceding embodiments, wherein the milk fat preparation is a dairy cream of 15% to 80% (w/w) fat content and contains milk proteins of from 0.1 to 2.5%. 10. A dairy product which contains vegetable oil, obtainable by a process according to any of the embodiments 2 to 9. 11. The dairy product of embodiment 10, which is selected from the group of products comprising milk drinks, fermented dairy products, ice cream products and chilled or frozen dairy desserts.

Claims

CLAIMS 1. A method for the production of an oil-dairy fat composite, which contains vegetable oil, comprising the steps of: i) Providing a vegetable oil,

ii) Providing a milk fat preparation,

iii) Combining the vegetable oil and the milk fat preparation into a mixture and subjecting said mixture to a homogenization to form the oil-dairy fat composite.

2. A method for the production of an emulsion, which contains vegetable oil and comprises the steps of: i) Providing a vegetable oil,

ii) Providing a milk fat preparation (a), being a milk cream,

iii) Combining the vegetable oil and the milk fat preparation (a) into a mixture and subjecting said mixture to a homogenization (a) to form an oil-dairy fat composite (a),

iv) Blending the oil-dairy fat composite (a) with a milk protein

composition (i) and processing said mixture by a homogenization step (b), to obtain an emulsion (a).

3. A method for the production of an emulsion, which contains vegetable oil and comprises the steps of: i) Providing a vegetable oil,

ii) Providing a milk fat preparation (b), being a milk fat preparation subjected to fat crystallization and subsequent mechanical treatment, iii) Combining the vegetable oil and the milk fat preparation (b),

preferably after removing the liquid milk fat, into a mixture and subjecting said mixture to a homogenization (a) to form an oil-dairy fat composite (b),

iv) Blending the oil-dairy fat composite (b) with a milk protein

composition (i), to obtain an emulsion (b).

4. The method according to claim 3, which further comprises a homogenization step (b), following the step of blending the oil-dairy fat composite (b) with a milk protein composition (i).

5. The method according to claim 3 or 4, wherein the subsequent mechanical treatment of the milk fat preparation (b) of step (ii), at least comprises mixing or shearing.

6. The method according to any one of claims 3 to 5, wherein the subsequent mechanical treatment of the milk fat preparation (b) of step (ii), further comprises centrifugation and removal of a liquid milk fat layer.

7. The method according to claim 2, wherein the milk fat preparation (a) is a milk cream, containing milk fat of from 10 to 80%, preferably of from 15 to 60%, more preferably of from 20 to 50% and most preferably of from 30 to 50% (w/w).

8. The method according to any one of claims 2 to 7, wherein homogenization (a) is carried out by mixing or dispersing, at a temperature in the range of from 10 to 65º C.

9. The method according to any one of claims 2 and 4 to 8, wherein homogenization (b) is carried out at a pressure of 10 to 250 bar and at a temperature in the range of from 10 to 65º C.

10. The method of any one of the preceding claims, wherein the vegetable oil is an unsaturated oil, preferably containing more than 40% of unsaturated fatty acids, more preferably more than 50% of unsaturated fatty acids.

11. An emulsion, obtainable by a method according to any one of claims 2 to 10.

12. The method for the production of an oil-dairy fat composite according to claim 1, wherein protein composition (i) is combined with the vegetable oil and the milk fat preparation, prior to subjecting said mixture to a homogenization.

13. The method of claim 12, wherein the milk fat preparation is milk fat preparation (b).

14. An emulsion, obtainable by a method according to claim 12 or 13.

15. A dairy product which contains vegetable oil, obtainable by using the method according to any one of claims 1 to 10, 12 or 13 or by using the emulsion according to claim 11 or 13, wherein the dairy product is selected from the group of products comprising milk drinks, fermented and/or non-fermented dairy products, aerated products, ice cream products and chilled or frozen dairy desserts.