RU2793406C2 - Method of producing products for baby food and milk products - Google Patents

Abstract

FIELD: dairy industry.

SUBSTANCE: method for producing baby food and milk product from fat free animal milk, the method comprising: (a) processing milk into a flow of casein, a flow of whey protein and a flow of lactose by combining microfiltration and ultrafiltration, wherein the flow of casein is generated during microfiltration as a retentate, the flow of whey protein is generated during ultrafiltration as a retentate and the flow of lactose is generated during ultrafiltration as a permeate; (b) combining the flow of whey protein generated at stage (a), and the source of lactose containing acid whey for preparation of a recombined flow; (c) preparation of a product for baby food from recombined flow generated at stage (b); and (d) preparation of a milk product from the flow of casein generated at stage (a) and fat free animal milk.

EFFECT: efficient utilization of dairy production waste.

14 cl, 1 dwg

Description

The invention relates to the field of milk processing, in particular the processing of skimmed animal milk. The invention relates to the production of baby food products, such as infant formula bases, as well as dairy products, from the same starting material. The invention also relates to a baby food product and a dairy product, which can be obtained by the method according to the present invention.

State of the art

Human milk is considered the "gold standard" for infant nutrition. Processing animal milk, such as cow's milk, to more closely resemble the composition of human milk is known in the art as "humanization" of animal milk. A method for humanizing animal milk includes changing the ratio of casein:whey proteins found in animal milk (e.g., approximately 80:20 for cow's milk) to a desired infant nutritional ratio found in human milk, e.g., 75:25 to 30:70 , or usually around 40:60, which is the ratio found in human milk at 0-6 months postpartum. In addition, the mineral content of animal milk is usually higher than the content found in human milk. Thus, the humanization of animal milk also includes the reduction of minerals.

The preparation of products suitable for use in baby food generally involves mixing, wet or dry, the various separately purified components in appropriate ratios. Existing manufacturing processes require several dairy ingredients from intermediary suppliers, including skimmed milk or its concentrate, including skimmed milk powder, demineralized whey or its concentrate, including demineralized whey powder, whey protein concentrates or isolates, usually in the form of powders, and pure lactose, usually in powder form, for inclusion in a nutritionally balanced infant formula.

Membrane filtration processes in the manufacture of baby food products from milk are known from WO 2013/137714, WO 2015/041529, US 5503865, EP 1133238, WO 2013/068653, WO 2014/163493 and WO 2014/163494. None of them disclose a productive and cost-effective way to reduce waste streams, in particular excess casein, which usually remains when milk is used to make baby food products. In WO 2015/041529 this excess casein is used to produce a food product suitable for infants aged 6-36 months.

There remains a need in the art for a method that will make it possible to efficiently and cost-effectively produce baby food products from milk, which will also reduce some of the waste streams.

The essence of the invention

The invention relates to a method for the simultaneous production of a baby food product and a dairy product from skimmed animal milk. The invention also relates to a baby food product obtained by the method according to the invention and a dairy product obtained by the method according to the invention. The method of the present invention includes

(a) converting the milk into a casein stream, a whey protein stream and a lactose stream by combining microfiltration and ultrafiltration, wherein the casein stream is formed as a retentate by microfiltration, the whey protein stream is formed by ultrafiltration as a retentate, and the lactose stream is formed by ultrafiltration as permeate;

(b) combining at least a portion of the whey protein stream formed in step (a) and a source of lactose to obtain a recombined stream;

(c) using the recombinant stream from step (b) in the manufacture of an infant formula product, and

(d) using part of the casein stream formed in step (a) and skimmed animal milk in the production of a dairy product.

The method of the invention elegantly allows all components of the incoming skimmed animal milk to be used and to minimize the amount of waste streams that are generated. According to a preferred embodiment, the method makes it possible to obtain both an infant food product and a dairy product from incoming skimmed animal milk as the sole source of protein. Another advantage of the process according to the invention is that both products are produced productively and cost-effectively with minimal enrichment requirements.

Preferred Embodiments

1. A method for producing a product for baby food and a dairy product from skimmed animal milk, including

(a) converting milk into a casein stream, a whey protein stream and a lactose stream by combining microfiltration and ultrafiltration, wherein the casein stream is formed as a retentate by microfiltration, the whey protein stream is formed by ultrafiltration as a retentate, and the lactose stream is formed by ultrafiltration as permeate;

(b) combining at least a portion of the whey protein stream from step (a) and a lactose source to obtain a recombined stream;

(c) using the recombinant stream from step (b) in the manufacture of a baby food product; And

(d) using at least a portion of the casein stream formed in step (a) and skimmed animal milk in the production of a dairy product.

2. The method according to embodiment 1, wherein the source of lactose comprises acid whey.

3. Process according to embodiment 2, wherein the acid whey used in the combination in step (b) is obtained as a by-product during the production in step (d).

4. Process according to embodiment 3, wherein the acid whey is obtained as a liquid stream from the separation step during production in step (d).

5. The method according to any of embodiments 2-4, wherein the sour whey is demineralized before being used as a source of lactose in step (b), the demineralization preferably comprising at least one of the steps of salt precipitation, electrodialysis, lactose crystallization and ion exchange, optionally in combination with nanofiltration.

6. A process according to any of the preceding embodiments, wherein at least a portion of the lactose stream formed in step (a) is used as a source of lactose in step (b) and/or is used in production in step (d).

7. Process according to embodiments 2 and 6 wherein the acid whey and at least a portion of the lactose stream from step (a) are combined and then subjected to demineralization according to embodiment 5 before being used as the source of lactose in step (b).

8. Process according to embodiment 6 or 7, wherein a portion of the lactose stream, preferably 50-95% by weight of the lactose stream, relative to the total mass of lactose, is used as the source of lactose in step (b) and a portion of the lactose stream, preferably the remainder, is used in production at step (d).

9. A process according to any of the preceding embodiments, wherein substantially all of the casein stream generated in step (a) is used in the production of step (d).

10. A process according to any one of embodiments 1-8, wherein a portion of the casein stream formed in step (a) is used in the production of step (d) and a portion of the casein stream, preferably the remainder, is combined in step (b) and included into the recombinant stream.

11. The method according to any of the preceding embodiments, wherein step (d) comprises combining the casein stream formed in step (a) with skimmed animal milk, preferably the weight ratio of protein from the casein stream to protein from skimmed animal milk is in the range of 0, 1-9.0, most preferably in the range of 0.5-2.0.

12. The method according to any of the preceding embodiments, wherein the skimmed animal milk used in steps (a) and/or (d), preferably in steps (a) and (d), is skimmed milk, preferably pasteurized skimmed milk.

13. A method according to any of the preceding embodiments, wherein the method further comprises

(i) treating the skimmed milk to remove bacteria, preferably by heat treatment or filtration, most preferably by pasteurization, to provide debacterized skimmed milk which is processed in step (a).

14. The method according to any of the preceding embodiments, wherein the processing in step (a) comprises

(ii) treating milk by microfiltration (MF) and obtaining MF retentate (MFR) and MF permeate (MFP) and

(iii) treating the MFP formed in step (ii) by ultrafiltration (UF) to obtain UF retentate (UFR) and UF permeate (UFP).

15. The method according to any of the preceding embodiments, wherein the volume concentration ratio at which the ultrafiltration step operates is in the range of 20-200.

16. The method according to any of the preceding embodiments, wherein the production in step (c) comprises at least one of the steps of drying, concentrating, adding vitamins, minerals, lipids and/or dietary fiber, packaging.

17. A method according to any of the preceding embodiments, wherein the dairy product is selected from the group consisting of cheeses, yoghurts and creams, preferably the dairy product is a fermented milk product selected from the group consisting of fermented dairy products and sour cheeses, most preferably the dairy product is strained yogurt.

18. The method according to any of the preceding embodiments, wherein the skimmed animal milk is the sole source of protein for the infant food product, preferably both the infant food product and the dairy product.

19. An infant food product obtained in step (c) of the method according to any one of embodiments 1-18.

20. Dairy product obtained in step (d) of the process according to any one of embodiments 1-18.

Detailed description

In the method according to the invention, skimmed animal milk is processed to obtain an infant food product and a dairy product. In the method, steps (a)-(c) refer to the production of a baby food product and steps (a) and (d) refer to the production of a dairy product. The present invention integrates a dairy product manufacturing process and a baby food product manufacturing process in order to minimize waste streams and produce both products productively and cost effectively at the same time with minimal fortification required. The inventors have surprisingly found that components normally discarded as waste in one form of product form excellent components for use in another product, so that waste streams are minimized and the need for fortification with other components is minimized. In other words, the casein that remains when a milk product is made from milk is excellent for use in the production of fermented milk products, and according to a preferred embodiment, the acid whey that remains when a dairy product is made from casein according to the present invention is excellent. for use in the manufacture of a baby food product.

The advantage of the present invention lies not only in the discovery that residual casein from the manufacture of baby food from milk is excellent for the manufacture of fermented milk products, but also in the discovery that acid whey, a by-product of the latter process, can be effectively used in the manufacture of a baby food product. from milk. Compared to separate processes, the combined process for producing a baby food product as well as a dairy product according to the present invention reduces the need for adding ingredients from outside, especially in the production of baby food products, while at the same time essentially all components of the incoming skim milk are used. , for valuable products. As such, the generation of waste is largely avoided, which is now quietly disposed of.

In a first aspect, the invention relates to a method for manufacturing a baby food product and a dairy product from skimmed animal milk, comprising

(a) converting milk into a casein stream, a whey protein stream and a lactose stream by combining microfiltration and ultrafiltration, wherein the casein stream is formed as a retentate by microfiltration, the whey protein stream is formed by ultrafiltration as a retentate, and the lactose stream is formed by ultrafiltration as permeate;

(b) combining at least a portion of the whey protein stream from step (a) and a lactose source to obtain a recombined stream;

(c) using the recombinant stream from step (b) in the manufacture of a baby food product; And

(d) using part of the casein stream formed in step (a) and skimmed animal milk in the production of a dairy product.

This method, including its preferred embodiments which are further defined below, is also referred to as the method of the invention.

In another aspect, the invention relates to an infant food product obtainable in step (c) of the method of the invention. In one embodiment, this aspect of the invention relates to an infant food product obtained in step (c) of the method of the invention.

In another aspect, the invention relates to a dairy product obtained in step (d) of the process of the invention. In one embodiment, this aspect of the invention relates to a dairy product obtained in step (d) of the method of the invention.

Here, it is preferred that the source of lactose comprises or is derived from acid whey, preferably acid whey obtained as a by-product during production in step (d). As such, the acid whey is recycled from the dairy product manufacturing process to the infant formula manufacturing process, making it especially efficient to use streams that are typically waste streams. In a preferred embodiment, the source of lactose is acidic whey, which is essentially devoid of minerals and proteins. The acid whey is preferably subjected to demineralization and/or protein removal steps to obtain said acid whey substantially devoid of minerals and proteins.

Here it is preferable that at least part, preferably all of the lactose stream formed in step (a) is used as a source of lactose (or part thereof) in step (b) and/or used in production in step (d). In one embodiment, the lactose source includes at least a portion of the lactose stream formed in step (a) and acid whey, preferably acid whey, obtained as a by-product during production in step (d).

It is preferred here that the entire casein stream generated in step (a) is used in steps (b) and (d). In one embodiment, substantially all of the casein stream generated in step (a) is used in the production of step (d). In one embodiment, a portion of the casein stream formed in step (a) is used in the production of step (d) and a portion of the casein stream, preferably the remainder, is used to be combined in step (b) and included in the recombined stream.

It is preferred here that the entire whey protein stream generated in step (a) is used in step (b).

In the context of the present invention, whenever a stream or composition is referred to as "formed at" some stage of the process, for example, a recombined stream formed at stage (b), said stream or composition may be a composition that is obtained directly from specified process step. In addition, if such directly obtained stream or composition is processed in one or more additional stages, for example, partial evaporation and/or addition of water or other components, the stream or composition is also considered to be formed at that particular stage of the method. Thus, if the recombined stream from step (b) can be partially stripped off before it enters the baby food product in step (c), the incoming stream to step (c) is still considered to be the recombined stream formed in step (b).

In one embodiment, the casein stream obtained in step (a) is used directly in step (d) without significant modification. In one embodiment, the whey protein stream obtained in step (a) is used directly in step (b) without significant modification.

In the context of the present invention, the term "flow" refers to a liquid composition, although the presence of some solid material, for example, in the form of a suspension, is not excluded, as long as the composition can be processed in conventional dairies.

The process according to the invention produces two different products: a baby food product and a dairy product, both of which are obtained from skimmed milk. In the context of the present invention, the term "baby food product" refers to milk-based nutritional compositions suitable for infant nutrition, which are usually in the form of a reconstituted powder or ready-to-use liquid composition, or refers to infant formula bases that are suitable for the manufacture of infant formula. and which include all or almost all of the necessary ingredients in the amounts required for nutrition of children. Preferably, the present method is a method for making infant formula, growing formula or bases therefor. In the context of the present invention, a baby food product is different from a dairy product. In one embodiment, the process of the invention is a process for the manufacture of an infant food product and also a dairy product.

The dairy product is preferably selected from the group consisting of cheeses, yoghurts and creams. In other words, a dairy product is a product that may or may not be a source for providing whey, a by-product at the time of its production. In the broadest sense of the present disclosure, a dairy product thus includes fresh cheeses such as sour milk cheese, fermented dairy products such as yogurt (stirred or thermostated yogurts), strained fermented dairy products such as strained yogurt (also referred to as concentrated yogurt or Greek yogurt).

In one embodiment, the dairy product is not infant formula (GUM) for children aged 6-36 months. In one embodiment, the dairy product is not a food product specifically designed for children aged 0 to 36 months.

Preferably the dairy product is a fermented milk product. In the context of the present invention, the term "fermented milk product" refers to fermented dairy products (e.g. yoghurts) and sour cheeses, during the production of which acid whey is formed as a by-product, for example, homemade cheeses, strained yoghurts or Greek yoghurts. Fermented milk products, during the production of which sour whey is formed as a by-product, are particularly preferred, since sour whey is advantageously used as a source of lactose in step (b) of the process according to the invention.

In a preferred embodiment, the fermented milk product is a strained fermented milk product. Methods for obtaining strained fermented dairy products are known in the art, for example from WO 2014/114970 or WO 2014/169171. As used herein, the term "sour cheese" refers to sour-type cheeses or "acid-coagulated cheeses" such as house cheese or similar types of cheese. As is known in the art, sour cheeses are those which provide acid whey as a by-product during their manufacture. In other words, in the production of sour cheeses, acids are used to form coagulates. Such methods for the production of sour cheeses are well known in the art. In one embodiment, the sour cheese is selected from cottage cheese and sour milk cheese. Preferably, the fermented milk product in connection with the present disclosure is a fermented dairy product or sour cheese, the production process of which includes the step of separating the whey from the coagulum. Such separation may include centrifugation, filtration and/or straining.

The process of the present invention uses milk as the starting material in steps (a) and (d). The skimmed animal milk is processed in step (a) and used in combination with at least a portion of the casein stream in the production of step (d). In the context of the invention, the term "skimmed milk" refers to milk with a reduced fat content compared to whole milk. Typically the fat content of skimmed milk is in the range of 0-2 wt.%, preferably 0-1 wt.%, more preferably 0-0.2 wt.%, most preferably 0-0.05 wt.% relative to the total weight of skimmed milk. In one embodiment, the skimmed milk is skimmed milk. The method of the present invention uses animal milk that is not human milk, preferably cow's milk. Most preferably skimmed cow's milk is used. In one embodiment, the method includes the step of skimming the milk to produce skimmed animal milk, which is then processed in step (a). In this case, full-fat animal milk, or animal milk or whole animal milk, is treated in a skimming step. The skimming step produces skimmed animal milk.

Incoming milk, before-after skimming, typically after a skimming step, may be subjected to debacterization (removal of bacteria), for example, by UV treatment, heat treatment (for example, microwave heating, pasteurization, such as HTST, ESL or UHT, or sterilization, for example , dry hot air sterilization or steam sterilization), or bacterial filtration (e.g. microfiltration). In the context of the present invention, debacterization refers to step (i). Such methods for reducing the bacterial load of milk are known in the art. In one preferred embodiment, the incoming milk is pasteurized.

Thus, in one embodiment, the skimmed animal milk used in steps (a) and/or (d), preferably in steps (a) and (d), is skimmed milk, preferably pasteurized skimmed milk.

Stage (a)

In step (a), the skimmed animal milk is processed or fractionated into a casein stream, a whey protein stream and a lactose stream. Here, the casein stream is a liquid composition comprising casein that is enriched in casein compared to the casein content of incoming skimmed animal milk, the whey protein stream is a liquid composition comprising whey protein that is enriched in whey protein compared to the whey protein content of incoming skim milk. animal milk, and the lactose stream is a liquid composition comprising lactose that is enriched in lactose compared to the lactose content of the incoming skimmed animal milk. In the context of the present invention, "enriched" means that the enriched component, on a dry weight basis, is increased in one stream compared to another. Thus, the casein stream is enriched with casein, i.e., has a higher casein content, on a dry weight basis, compared to the incoming skimmed animal milk.

The protein fraction of the casein stream formed in step (a) typically contains some whey protein, preferably less than 15% by weight, more preferably less than 10% by weight of the protein fraction of the casein stream, and a lot of casein. Preferably the protein fraction comprises at least 85% by weight of casein, more preferably the protein fraction comprises at least 90% by weight of casein. The total solids content of the casein stream typically ranges from 5 to 30 wt.%, preferably ranges from 7 to 30 wt.%, most preferably from 17 to 24 wt.% of the total weight of the casein stream. The casein stream is preferably a microfiltration retentate (MFR). Casein flow can also be referred to as casein concentrate, casein isolate, micellar casein concentrate, or micellar casein isolate (MCI).

The whey protein stream is typically a liquid composition having a total solids content of 5-35 wt%, preferably 10-30 wt%, most preferably 20-30 wt%, and typically comprises 25-90 wt%, preferably 60 -85 wt.% whey proteins relative to the total dry weight. The whey protein stream is preferably an ultrafiltration retentate (UFR). A whey protein stream may also be referred to as an aqueous composition comprising whey proteins.

Although the whey protein stream is enriched in whey protein compared to the incoming skimmed milk, it may still contain significant amounts of casein, depending on the stringent conditions under which casein and whey protein fractionation is performed, typically by ultrafiltration. In one embodiment, the whey protein stream comprises at most 40% by weight, preferably 5-20% by weight casein, based on total protein weight. Such changes in fractionation conditions and accompanying changes in whey protein flux are known in the art. Depending on the amount of casein present in the whey protein stream, the amount of casein used in the combining step (b) can be adapted such that the infant formula has a whey protein:casein ratio that lies in the preferred ratio of 90:10-40: 60.

The lactose stream is typically a liquid composition with a total solids content of 3-30% by weight, preferably 5-22% by weight. The lactose content of the lactose stream formed in step (a) is typically at least 75 wt.%, preferably at least 90 wt.% or even at least 95 wt.% of the total dry matter.

Fractionation in step (a) is performed by membrane filtration methods and includes a combination of microfiltration and ultrafiltration. The casein stream is formed by microfiltration as retentate, the whey protein stream is formed by ultrafiltration as retentate, and the lactose stream is formed by ultrafiltration as permeate. Suitable membrane filtration methods are known in the art, such as those disclosed in WO 2013/068653, WO 2013/137714 and WO 2015/041529.

In one embodiment, step (a) comprises

(ii) microfiltration (MF) of milk and obtaining MF retentate (MFR) and MF permeate (MFP), and

(iii) ultrafiltration (UF) of the MFP formed in step (ii) and obtaining UF retentate (UFR) and UF permeate (UFP).

In the microfiltration step (ii) the skimmed animal milk is fractionated into two different streams, each enriched with a certain type of protein; casein enriched MF retentate (MFR) and whey protein enriched MF permeate (MFP) are produced. The MF in step (ii) is performed through a membrane which allows the fractionation of casein and whey protein. Such a membrane typically has a porosity of 0.05-0.35 microns. Preferably, a ceramic membrane or a spiral (organic) membrane is used.

According to a preferred embodiment, the microfiltration in step (ii) is enhanced by diafiltration (DF). Diafiltration can be performed by diluting the MF retentate at least once with some water, or by diluting the incoming skim milk with some water and subjecting the diluted animal milk to MF. The DF water can be added to the incoming animal skimmed milk or MFR once, or the total amount of DF water can be added in multiple doses. After each addition of water for DF to incoming animal skimmed milk or MFR, the diluted liquid composition is subjected to MF.

During ultrafiltration in step (iii), most of the liquid and few solutes end up in the UF permeate (UFP), while the UF retentate (UFR) includes substantially all of the whey protein in a smaller volume. Small molecules that permeate the UF membrane are, for example, lactose, monovalent and polyvalent ions. The ultrafiltration in step (iii) can be performed with any UF membrane known in the art, including ceramic membranes, tubular membranes, and organic helical membranes. Preferably the UF membrane is an organic helical membrane. The UF membrane cuts off the molecular weight that allows proteins, preferably whey proteins, to remain in the retentate and allows low molecular weight solutes such as lactose to pass through the membrane. The UF in step (iii) is preferably carried out with a membrane having a molecular weight cutoff of at most 25 kDa, preferably at most 10 kDa, and preferably at least 2.5 kDa, preferably at least 5 kDa. The UF in step (iii) is preferably carried out with a volume concentration factor (VCF) in the range of 20-200, preferably 50-150, which is found to provide the most optimal results in terms of UF retentate composition.

In the context of the invention, the term "volume concentration factor" or "VCF" is the ratio by which a liquid composition is concentrated after filtration, i.e., the total volume of the incoming stream before filtration divided by the total volume of the retentate after filtration, regardless of the total solids content substances. Thus, when 5 L of liquid composition is fractionated through an ultrafiltration membrane into 4 L of permeate and 1 L of retentate, such a UF process operates with a VCF of 5/1=5.

Step (a) may further include one or more concentration steps such as concentrating the MFR generated in step (ii) and/or the UFR generated in step (iii). Concentration is preferably performed by reverse osmosis (RO), nanofiltration (NF) and/or evaporation. NF is most preferred because NF concentrates the flux and at the same time reduces the amount of monovalent ions that are able to permeate through the NF membrane. Such a reduction in the content of monovalent ions is usually desirable in the manufacture of baby food products.

Demineralization

The method of the invention preferably includes a demineralization step in which the lactose source or one or more of its components are demineralized before being subjected to step (b). Therefore, at least part of the lactose stream formed in step (a) and/or the acid whey formed in step (d) is usually demineralized, preferably at least the acid whey formed in step (d) is subjected to demineralization before being processed to step (b). Demineralization is especially preferred in the production of baby food products, which usually require a lower mineral content compared to incoming milk.

Thus, in one embodiment, the acid whey, preferably the acid whey formed in step (d), is demineralized before being used as (part of) the source of lactose in step (b). Similarly, in one embodiment, at least a portion of the lactose stream formed in step (a), preferably the UFR formed in step (iii), is demineralized before being used as (part of) the source of lactose in step (b).

In the case where the lactose stream formed in step (a) is not treated in step (b), but, for example, in step (d), demineralization of the lactose stream is usually not required, since the desired mineral content in dairy products is usually more or less corresponds to the content of minerals in the incoming milk. In the case where a portion of the lactose stream formed in step (a) is treated in step (b) and a portion is treated in step (d), preferably only the portion that is treated in step (b) is demineralized first.

In a preferred embodiment, the acid whey that is formed in step (d) is processed in step (b) as a source of lactose (or part thereof) and then processed in step (c) to produce a baby food product. Thus, it is preferred that the acid whey is demineralized before step (b). Therefore, in a preferred embodiment, the acid whey formed in step (d) is combined with a portion of the lactose stream formed in step (a), if any, and the combined lactose source is demineralized prior to being processed in step (b).

Demineralization of the lactose source can be accomplished by any method known in the art such as electrodialysis, ion exchange, salt precipitation, lactose crystallization, membrane filtration techniques such as nanofiltration, optionally enhanced by diafiltration, or a combination thereof. In a preferred embodiment, demineralization comprises at least one of salt precipitation, electrodialysis, lactose crystallization and ion exchange, optionally in combination with nanofiltration, more preferably, demineralization comprises nanofiltration in combination with at least one of salt precipitation, electrodialysis, lactose crystallization and ion exchange. In a preferred embodiment, demineralization comprises at least electrodialysis and/or salt precipitation. In one preferred embodiment, demineralization comprises at least nanofiltration in combination with electrodialysis and/or salt precipitation. The inventors have found that when only nanofiltration is used for demineralization, in particular for demineralization of ultrafiltration permeate as a source of lactose in the production of baby food, the content of divalent ions such as calcium ion and phosphate ion is usually not reduced enough to obtain the final product for baby food in accordance with regulatory requirements.

Demineralization is preferably carried out so that at least 20 wt.% or preferably 50 wt.%, more preferably at least 70 wt.% or at least 80 wt.%, most preferably at least 90 wt.% of polyvalent ions are removed, and/or so that at least 20 wt.% of monovalent ions are removed, preferably at least 35 wt.% or at least 50 wt.%, most preferably at least 60 wt.% of monovalent ions present in the stream are removed lactose, for example UFR formed in step (iii).

Step (b)

In step (b), at least a portion of the whey protein stream from step (a) is combined with a source of lactose to form a recombined stream. This recombinant stream is used to manufacture the baby food product in step (c). The combination in step (b) gives a composition with a protein fraction comprising both casein and whey protein in a defined weight ratio. The combination in step (b) may include additional components such as part of the casein stream formed in step (a). Since the whey protein stream may contain significant amounts of casein, it is not always necessary to combine with a portion of the casein stream formed in step (a). In such a case, the entire casein stream is preferably used in step (d) in order to minimize waste streams.

The combination is preferably carried out so that the weight ratio of whey protein to casein in the recombined stream is in the range of 90:10-40:60, more preferably in the range of 80:20-50:50, even more preferably in the range of 75:25-50:50, most preferably in the range of 70:30-55:45. In one embodiment, the weight ratio of whey protein to casein in the recombinant stream is about 60:40. The exact ratio is usually determined by the type of baby food product being produced and can be adjusted as is known in the art. In addition, much attention in technology is paid to the amino acid profile of baby food products. The method of the invention provides optimal flexibility in achieving the specific desired amino acid profile, for example by adjusting the ratio in which the whey protein and casein streams are combined, or by changing the specific conditions of the microfiltration process in step (a). As such, optimal amino acid profiles similar to those found in human milk can be obtained using the method of the invention.

Since infant formulas typically need to be lower in casein and higher in whey protein, which are present in the skimmed animal milk that is processed in step (a), not all of the casein stream is required to recombine with the whey protein stream. In the present invention, this remaining casein, which is currently discarded in most cases, is transferred to useful use in production in step (d).

Typically, the entire casein stream generated in step (a) is used in either step (b) or step (d), so that casein is also not left or is not left unused. In other words, the casein stream formed in step (a) is preferably divided between steps (a) and (d). Thus, it is preferable that part of the casein stream formed in step (a) is used in the production of step (d) and part of the casein stream, preferably the remainder, is combined in step (b) and included in the recombined stream. In another embodiment, substantially all of the casein stream generated in step (a) is used in the production of step (d).

In one embodiment, 10-50 wt.%, preferably 12-25 wt.% of the total weight of casein in the stream of casein formed in stage (a), is subjected to the processing stage (b). Most preferably, about 16 wt.% of the total mass of casein in the stream of casein formed in stage (a) is subjected to processing in stage (b). Most preferably, the remainder is processed in step (d). The amount of casein stream formed in step (a) that is processed in step (b) is advantageously controlled by the desired weight ratio of whey protein to casein in the recombinant stream.

Preferably, the entire whey protein stream formed in step (a) is pooled in step (b). Similarly, in the case where the acid whey formed in step (d) is used in the source of lactose, it is preferable that all the acid whey formed in step (d) be treated in step (b). This use of the whey protein formed in step (a) and the acidic whey formed in step (d) minimizes the amount of waste that is discarded in the process and gives optimum utilization of all components of the incoming milk.

The presence of lactose is generally required for both the production of the baby food product in step (c) and the production of the dairy product in step (d), especially when the dairy product is yogurt. Therefore, in the process according to the invention, it is preferable that at least part of the lactose stream, preferably the entire stream formed in step (a), is treated in step (b) and/or in step (d). In a preferred embodiment, the lactose stream formed in step (a) is divided between steps (b) and (d). Thus, in one embodiment, at least a portion of the lactose stream formed in step (a) is treated in step (b). In this embodiment, step (b) comprises combining at least a portion of the whey protein and lactose streams from step (a) and at least a portion of the acid whey from step (d) and preferably a portion of the casein stream from step (a) to the recombined stream.

In one embodiment, 0-50 wt.%, preferably 5-25 wt.% of the total mass of lactose in the lactose stream formed in stage (a) is treated in stage (b) as a source of lactose (or part of it). Most preferably, the remainder is processed in step (d). The amount of lactose stream formed in step (a) that is treated in step (b) as a source of lactose (or part thereof) is predominantly controlled by the amount of lactose required for step (d). In the event that the amount of lactose in the lactose stream formed in step (a) which is processed in step (b) may not be sufficient to produce a baby food product, additional lactose which is present in the acid whey formed in step (d). It follows that not all of the lactose from the lactose stream may be required to provide the desired lactose content in the recombinant stream, so that the remaining lactose can be advantageously used in step (d) as an additive during the production of the fermented milk product, which also reduces waste.

In one embodiment, a portion of the casein stream is combined with the entire whey protein stream, a portion of the lactose stream, and all acid whey. In one embodiment, a portion of the casein stream is combined with the entire whey protein stream, the entire lactose stream, and the entire acid whey stream. In one embodiment, a portion of the casein stream is combined with the entire whey protein stream and the entire acid whey without the lactose stream.

In one embodiment, a portion of the MFR generated in step (ii) is combined with at least a portion of the UFR generated in step (iii) and the acid whey generated in step (d).

In step (b), two or more streams are recombined into one stream. Such recombination can occur once (streams are combined simultaneously) or in stages (streams are combined sequentially). In one embodiment, the acid whey formed in step (d) is combined with the lactose stream formed in step (iii) prior to demineralization so that they can both be demineralized before being combined with the casein and whey protein streams. The combination can be performed as wet blending or dry blending or even as a combination of both. Preferably, the combination takes place as wet mixing, in which the liquid compositions are mixed in appropriate amounts.

Stage (s)

In step (c), the recombinant stream generated in step (b) is used to manufacture a baby food product. Such production is known in the art and typically includes one or more of drying, concentration, addition of vitamins, minerals, lipids and/or dietary fiber, heat treatment, homogenization, packaging. In a preferred embodiment, step (c) does not include heat treatment and includes one or more of drying, concentrating, adding vitamins, minerals, lipids and/or dietary fiber, and packaging. Preferably step (c) includes at least a drying step, most preferably all of the above steps.

Although one or more separate streams may be dried prior to being combined in step (b), it is preferable to dry the recombined stream formed in step (b), preferably by spray drying. As such, only one drying step is needed in the manufacture of a baby food product. In addition, drying generally reduces the native protein content, and performing multiple drying steps in this manner results in a reduced native protein content in the final baby food product. In a preferred embodiment, the process of the invention comprises only one drying step, where the recombinant stream is dried in step (c), preferably by spray drying. Due to the inherent limited heat load imposed on the liquid nutritional composition by spray drying, significant amounts of protein remain native during this stage so that the native protein content of the final infant formula product is as high as possible.

In one embodiment, the recombinant stream is preferably concentrated prior to drying. Such concentration can be performed by any means known in the art, such as reverse osmosis (RO), nanofiltration (NF) and/or evaporation.

The heat treatment is known in the art and may be, for example, pasteurization such as HTST, ESL or UHT, or sterilization such as dry hot air sterilization or steam sterilization. In a preferred embodiment, debacterised, preferably pasteurized, skimmed milk is used as the incoming milk, so that no additional heat treatment is required in the production in step (c).

Depending on the type of baby food product desired, the addition of certain components such as vitamins, minerals, lipids and/or dietary fiber may be desirable. This addition can be done before, during or after the combination in step (b), and/or optionally before or after the drying step. The specialist knows the requirements for certain types of baby food products, for example, from EU Directive 91/321/EEC or EU Directive 2006/141/EC, or from the US Food and Drug Administration, 21 CPR Ch 1 part 107, and is able to adjust the composition of the recombined stream in order to meet these requirements.

In one aspect, the present invention relates to a product for baby food, which can be obtained by the method according to the invention, i.e., can be obtained in stage (c). The inventors have found that the digestibility of the protein fraction in the baby food product according to the invention, i.e., which can be obtained by the method according to the invention, is improved compared to the protein fractions of known baby food products. In the present description, improved digestibility refers to the digestibility, closer to the digestibility of human milk. Digestibility is generally referred to as the rate of digestion, preferably the rate of protein digestion. In addition, the whey protein produced by the method of the present invention constitutes an economically attractive source for inclusion in infant formulas.

In one aspect, the present invention relates to whey protein as present in the whey protein stream obtained by the method of the invention, i.e., obtained in step (a), which is included in the baby food product obtained in step (c). Said protein product exhibits improved digestibility also in dry form. Said whey protein is preferably present with casein in a whey protein:casein ratio in the range of 90:10-40:60, more preferably in the range of 80:20-50:50, even more preferably in the range of 75:25-50:50, most preferably in the range 70:30-55:45. The whey protein obtained according to the present invention shows digestion kinetics closer to human milk than existing commercial infant formula.

The expert can determine the degree of digestibility, for example, from Van de Braak et al. ( Clin. Nutr., 2013 , 32, 765-771). The preferred method for determining digestibility is the method according to the following digestibility test.

Digestibility Test

Conditions in the stomach and intestines are successfully simulated in serial bioreactors in a system of parallel bioreactors. In each reactor, the conditions are dynamic in the sense that the pH follows a predetermined curve and fresh artificial digestive juices are continuously added. Biochemical conditions in the stomach and intestines, i.e., enzyme activity, bile concentration and pH, are adjusted to mimic conditions in infants given a 200 ml dose of infant formula. Digestion in the stomach is simulated by adding a pepsin/lipase solution (dose 10 ml + 0.5 ml/min) containing 37.5 mg of lipase (DF Amano 15) and 15 mg of pepsin (Sigma P7012) per 300 ml, at the same time time gradually lower the pH to 4.3 by adding HCl over 2 hours. Intestinal digestion is simulated at neutral pH (7.2) after addition of sodium hydroxide/sodium carbonate and pancreatin/bile extract mixture (dose 45 ml+1 ml/min) containing 7.5 g pancreatin (4×USP, Pfizer) and 2.5 g bile extract (pig bile powder, Sigma B8631) per 500 ml, in 2 hours. Samples are taken at regular intervals to monitor protein digestion over time. The samples are subjected to chemical analysis, including analysis of substrate consumption by SDS-page, generation of primary amino groups by OPA, formation of small peptides by SEC-HPLC and formation of free amino acids by UPLC. Using such a protocol, one can easily compare the digestion rate of one component, such as a protein source, or food product containing a protein source, with the digestion rate of another protein source, or food product containing a protein source.

In another preferred embodiment, the present invention relates to an infant formula obtained in step (c) containing the milk proteins obtained by the method of the present invention, i.e., obtained in step (a). Said milk proteins preferably comprise whey protein and casein, preferably present in a ratio in the range of 90:10-40:60, more preferably in the range of 80:20-50:50, even more preferably in the range of 75:25-50:50, most preferably in interval 70:30-55:45. Whey protein and casein obtained according to the present invention show digestion kinetics closer to human milk than existing commercial infant formula.

In one aspect, the invention relates to a method or use for improving the digestibility of a protein fraction included in an infant food product, comprising obtaining an infant food product by the method of the present invention. In one aspect, the invention relates to a method or use for feeding an infant, preferably an infant aged 0-6 months, comprising administering to said infant an infant formula according to the invention.

Stage (d)

In step (d), a portion of the casein stream is further processed to produce a dairy product, preferably a fermented milk product. In a preferred embodiment, acidic whey is produced as a by-product. The dairy product is produced from at least a portion of the casein stream formed in step (a) and skimmed animal milk. Preferably the skimmed animal milk is the same animal milk that is processed in step (a) and preferably goes through the same pre-treatment steps, if any.

Acid whey, also called sour whey, is a by-product of the normal process of making fermented milk products and is usually discarded as waste. Acid whey includes valuable compounds such as lactose. With the rapidly increasing demand for fermented milk products, in particular yoghurts, the increasing stream of acid whey waste is becoming a major problem for the dairy industry, which the present invention elegantly solves. Preferably, part or all of the lactose stream formed in step (a) is used in the production of step (d).

Any methods known in the art for the production of dairy products can be used in step (d), for example, a method for the production of cheeses, yoghurts or cream. Step (d), as is known in the art, typically includes a process for producing a fermented milk product such as sour cheese or yogurt, preferably blended or strained yogurt, from casein.

Step (d) typically includes a pooling step in which the casein stream formed in step (a) is combined with skimmed animal milk and optionally with one or more (additional) sources of whey protein (e.g. whey protein concentrate (WPC), whey isolate protein (WPI)), cream, minerals and lactose. Here, the skimmed animal milk is preferably the same skimmed animal milk that is processed in step (a). Here the lactose may come from step (a), from the demineralization step, preferably from the demineralization step of the present invention, or from an external source, most preferably the lactose at least partially comes from step (a). The minerals are preferably added, most preferably in the form of the lactose stream formed in step (a), which has not been demineralized. The combining step is typically the first step in step (d). Most preferably, the casein stream formed in step (a) is combined with a source of whey protein. Preferably, such a combination is the first step in the production of step (d). In other words, the dairy product is produced from a mixture comprising at least a portion of the casein stream formed in step (a) and skimmed animal milk, and optionally one or more of the additional components listed above. The combination is preferably performed such that the weight ratio of protein from the casein stream to protein from skimmed animal milk is in the range of 0.1-9.0, most preferably in the range of 0.5-2.0.

The presence of animal milk ensures that whey protein and lactose are present during the production of the dairy product. In the production of step (d), an additional source of lactose can also be used, such as the lactose stream (or part thereof) formed in step (a), and preferably in step (d) it is combined with the casein stream formed in step (a) , and skimmed animal milk.

Step (d) preferably includes a centrifugation step in which the solids, which eventually form the dairy product, are separated from the liquid stream, which is obtained as acid whey. In a preferred embodiment, the acid whey used in the lactose stream is obtained as a liquid stream from the centrifugation step during production in step (d). The combination of casein, whey protein and lactose for the production of dairy products is known in the art and can be carried out as the expert believes.

Typically, the entire casein stream generated in step (a) is used in either step (b) or step (d) so that no excess casein remains. In one embodiment, based on the weight of casein, 50-90% by weight, preferably 75-88% by weight of the casein stream formed in step (a) is treated in step (d). Most preferably, based on the total weight of casein, about 84% by weight of the casein stream formed in step (a) is processed in step (d). Most preferably, the residue is treated in step (b).

Similarly, it is preferred that the entire lactose stream generated in step (a) is used in either step (b) or step (d) so that no excess lactose remains. In one embodiment, based on the total weight of lactose, 50-100% by weight, preferably 75-95% by weight of the lactose stream formed in step (a) is treated in step (d). Most preferably, the residue is treated in step (b).

In a preferred embodiment, skimmed animal milk is the sole source of protein for both products that are produced by the process of the invention. Preferably all the protein in the dairy product that is obtained in step (d) comes from the casein stream and optionally from the same animal skimmed milk that is processed in step (a). Essentially, animal skimmed milk is the only source of protein for a dairy product.

Any other additive or component known in the art suitable for the production of dairy products may be added to the casein stream, animal milk, or a combination thereof. Suitable additives include milk fat, stabilizers, sweeteners, flavors, and the like. The use of milk fortified with such additives in the manufacture of dairy products is known in the art.

In a preferred embodiment, the production of the dairy product in step (d) produces acid whey as a by-product, which is usually discarded as waste. Acid whey is known in the art and is the name given to the whey stream that is obtained in the production of fermented milk products such as yoghurts and sour cheeses. Acid whey is usually a liquid composition having a pH of at most 5.5 or even 5.1. Acid whey usually contains, on a total dry weight basis, 50-90 wt.%, preferably 60-75 wt.% lactose and 0-20 wt.%, preferably 10-15 wt.% whey protein. Acid whey also typically includes minerals, including calcium, potassium, magnesium, sodium, chloride, and phosphate. The total amount of ash in acid whey is typically in the range of 8-20 wt.%, preferably 10-15 wt.% of the total dry weight.

The acid whey that is formed in step (d) is preferably combined in step (b) for use as a source of lactose (or part thereof) in the manufacture of a baby food product. The ash content of the acid whey can be undesirably high and is therefore preferably reduced by demineralization before being combined in step (b) with the whey protein stream and possibly part of the casein stream formed in step (a). In one embodiment, the acid whey formed in step (d) is combined with the lactose stream prior to demineralization of the combined lactose and acid whey streams. In the event that demineralization of the lactose stream may not be required, the acid whey may be demineralized before being combined with the lactose stream without it. Such demineralization can be carried out by any method known in the art.

Drawing

The drawing shows a preferred embodiment of the method according to the invention. Dashed arrows show preferred embodiments. MF=microfiltration; UF=ultrafiltration; Deminer = demineralization; D=dairy product; IF=baby food product; L=source of lactose. The various streams are represented by numbers 1-8: 1=skimmed, preferably debacterised, animal milk; 2=microfiltration retentate; 3=microfiltration permeate; 4=ultrafiltration retentate; 5=ultrafiltration permeate; 6=recombined stream; 7=acid whey; 8=demineralized lactose.

Claims (21)

1. A method for producing a product for baby food and a dairy product from skimmed animal milk, including: (a) converting milk into a casein stream, a whey protein stream and a lactose stream by combining microfiltration and ultrafiltration, wherein the casein stream is formed by microfiltration as a retentate, the whey protein stream is formed by ultrafiltration as a retentate, and the lactose stream is formed by ultrafiltration as a permeate; (b) combining the stream of whey protein formed in stage (a) and source of lactose containing acidic whey, to obtain a recombined stream; (c) obtaining a baby food product from the recombinant stream formed in step (b); And (d) obtaining a dairy product from the casein stream formed in step (a) and skimmed animal milk. 2. The process according to claim 1, wherein the acid whey used in the combination in step (b) is obtained as a by-product during the production in step (d). 3. Process according to claim 2, wherein the acid whey is obtained as a liquid stream from the separation step during production in step (d). 4. The method according to any one of the preceding claims, wherein the acid whey is demineralized before being used as a source of lactose in step (b), the demineralization preferably comprising at least one of the steps of salt precipitation, electrodialysis, lactose crystallization and ion exchange, optionally combinations with nanofiltration. 5. The process of claim 4, wherein the acid whey and the lactose stream from step (a) are combined and then subjected to the demineralization of claim 4 before being used as the source of lactose in step (b). 6. Process according to any one of the preceding claims, wherein 0-50% by weight of the total mass of lactose in the lactose stream formed in step (a) is treated in step (b) as a source of lactose. 7. Process according to any of the preceding claims, wherein the skimmed animal milk used in steps (a) and/or (d), preferably in steps (a) and (d), is skimmed milk, preferably pasteurized skimmed milk. 8. The method according to any one of the preceding claims, wherein the entire whey protein stream formed in step (a) is pooled in step (b). 9. The method according to any one of the preceding claims, wherein a portion of the casein stream formed in step (a) is used in the preparation of step (d) and a portion of the casein stream formed in step (a) is combined in step (b) and included in the recombined stream. 10. A method according to any one of the preceding claims, further comprising: (i) treating the skimmed milk to remove bacteria, preferably by heat treatment or filtration, most preferably by pasteurization, to provide debacterized skimmed milk which is processed in step (a). 11. A method according to any one of the preceding claims, wherein the processing in step (a) comprises: (ii) processing milk by microfiltration (MF) and obtaining MF-retentate (MFR) and MF-permeate (MFP) and (iii) treating the MFP formed in step (ii) by ultrafiltration (UF) to obtain UF retentate (UFR) and UF permeate (UFP). 12. The method according to any one of the preceding claims, wherein the volume concentration ratio at which the ultrafiltration step operates is in the range of 20-200. 13. The method according to any one of the preceding claims, wherein the production in step (c) comprises at least one of the steps of drying, concentrating, adding vitamins, minerals, lipids and/or dietary fiber, packaging. 14. The method according to any one of the preceding claims, wherein the skimmed animal milk is the sole source of protein for the infant food product, preferably both the infant food product and the dairy product.

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