Process for producing a triglyceride-phospholipid composition

Abstract

A process for producing a triglyceride-phospholipid concentrate is provided, the process comprising: providing an egg yolk lecithin solution from the extraction of an egg yolk material with a liquid extractant, mixing the egg yolk lecithin solution with an OPO triglyceride carrier comprising 1,3-dioleoyl-2-palmitoylglycerol and having a ratio of palmitic acid in the 2-position of the triglycerides relative to the total palmitic acid in the triglycerides (SN2-C16:0) of at least 50%, and a C52 triglyceride content of at least 42 wt.%, and separating the liquid extractant from the mixture to produce a triglyceride- phospholipid concentrate comprising the OPO triglyceride carrier and egg lecithin.

Description

[0001] Process for Producing a Triqlyceride-Phospholipid Composition

[0002] The present invention relates to triglyceride compositions and processes for the production of triglyceride compositions. In particular, the present invention relates to triglyceridephospholipid concentrates and processes for producing triglyceride-phospholipid concentrates. The present invention also relates to infant formula and fat blends for use in infant formula.

[0003] Background

[0004] Fat forms a crucial component of infant formula. It provides an important source of energy, and various fatty acids can aid brain, eye, nervous system development, by way of example. Natural human milk is composed so as to provide optimal absorption of the fat. This relates, amongst other factors, to triglyceride and phospholipid structure and the presence of other nutrients such as cholesterol.

[0005] One important nutrient in human milk is choline. WO 2021 / 086255 describes the use of natural egg and milk phospholipids to provide bioavailable choline in the form of phospholipid-bound choline such as phosphatidylcholine, lysophosphatidylcholine or sphingomyelin.

[0006] In addition, cholesterol is an important nutrient to aid the absorption of fats, particularly because in infants the bile system (essential for fat absorption) is not yet fully developed.

[0007] Egg phospholipids or lecithin can be obtained in various different ways, including extraction or washing with organic solvents, using supercritical CO2, chromatography, enzymatic hydrolysis, cryo-precipitation or membrane separation. The resulting product is typically either a concentrated pure egg lecithin (for example when non-phospholipid fats in egg yolk are removed by solvent washing, such as with acetone), or a dilute extract solution of egg lecithin. However, pure isolated egg lecithin obtained after extraction, for example after solvents are removed, can be difficult to handle and integrate into production processes due to its nature as a sticky viscous paste. This is a particular problem for egg phospholipids, for example compared to vegetable lecithin such as soy lecithin, due to high levels of polar phospholipids such as phosphatidyl choline. In addition, where the desired end-use is in food, and particularly in infant formula, use of egg lecithin extracts as a dilute solution or suspension with solvents that cannot be present in the final product is also undesirable. In some cases, lecithin extracts can be spray dried to form a powder, but the phospholipid content, particularly phospholipid-bound DHA (docosahexaenoic acid) and ARA (arachidonic acid), must be relatively low to form such powders and so this is not a useful option for egg lecithin.

[0008] In order to mimic natural human milk and obtain the associated absorption, the fat component should contain a significant portion of beta palmitate triglycerides, and particularly 1 ,3-dioleoyl-2-palmitoylglycerol “OPO”. OPO-containing fat may provide benefits to infants such as reducing constipation, improving calcium or fatty acid absorption and enhancing bone development. A fat blend enriched in OPO triglyceride may be blended with other components of an infant formula in order to enhance the absorption of beneficial fats and better mimic human milk. According to the Chinese National Food Safety Standard GB 30604-2015, the proportion of palmitic acid at the 2-position is at least 52% of the total palmitic acid, and the content of OPO is at least 40 weight percent.

[0009] There is therefore a desire for improved processes and products to address the above- mentioned needs in fat products for infant formula.

[0010] Summary

[0011] It has been found that the introduction of egg phospholipids into a fat blend for infant formula, without introducing undesirable solvents, can result in problems for handling and processing efficiency. For example, concentrated pure egg lecithin or phospholipids can form a viscous and sticky paste that poses handling problems at the point of manufacture and is not easily usable in the process of producing a fat blend.

[0012] A carrier may be used by mixing the carrier with the egg lecithin to improve handling. However, solvents used in the extraction of egg lecithin are in themselves undesirable, and in many cases will be prohibited, for inclusion in an infant formula. Solvents may also pose a problem in terms of inclusion of a dilute egg lecithin-solvent solution in a fat blend, as the solvent may not mix well with the fats being used. One way that has been found to address these problems is to introduce a fat or oil carrier (such as a triglyceride carrier). For example, egg lecithin may be extracted from egg yolk using a solvent, and the extract solution can then be mixed with a fat or oil carrier before removing the solvent. In this way, concentrated pure egg lecithin may be avoided, which aids handling, while a triglyceride fat carrier can be acceptable for inclusion into a fat blend for an infant formula.

[0013] It has also been found that carriers such as vegetable oils can often separate from phospholipids during storage, which leads to difficulties in dosing the product accurately into a fat blend without additional processing. For example, a separated product will typically require additional blending steps to provide a product that can be reliably integrated into a fat blend. It has nonetheless been found that vegetable oils that might typically be used as a neutral fat for addition to infant formula (for example to add fat without negatively affecting the triglyceride profile), such as high oleic sunflower oil, can contain unwanted phytosterols that also make their use undesirable. Phytosterols can act to decrease absorption of cholesterol, which is undesirable in infant formula where cholesterol provides nutritional benefits.

[0014] The present inventors have surprisingly found that a fat comprising 1 ,3-dioleoyl-2- palmitoylglycerol, OPO, can be used as a carrier that addresses handling problems due to the viscosity of pure egg lecithin, as well as addressing separation problems of liquid vegetable oils when in a mixture with egg phospholipids. In addition, OPO-containing fat also provides benefits associated with increased OPO content in an infant formula.

[0015] An aspect of the invention provides a process for producing a triglyceride-phospholipid concentrate comprising: providing an egg yolk lecithin solution from the extraction of an egg yolk material with a liquid extractant; mixing the egg yolk lecithin solution with an OPO triglyceride carrier comprising 1 ,3-dioleoyl-2-palmitoylglycerol and having a ratio of palmitic acid in the 2-position of the triglycerides relative to the total palmitic acid in the triglycerides (SN2-C16:0) of at least 50%, and a C52 triglyceride content of at least 42 wt.%; separating the liquid extractant from the mixture to produce a triglyceride- phospholipid concentrate comprising the OPO triglyceride carrier and egg phospholipids. By using a fat comprising 1 ,3-dioleoyl-2-palmitoylglycerol (referred to herein as “OPO”) as a carrier following the extraction of egg lecithin from egg yolk, it has been surprisingly found that problems of handling and storage of the mixture may be addressed at the same time as providing a beneficial nutritional profile for an infant formula fat blend. Without wishing to be bound by any particular theory, it is believed that the melting point of the OPO enriched fat is sufficiently low so as to permit crystallisation of the fat at ambient temperature, which provides a solid mixture with egg lecithin and prevents splitting of the mixture during storage. In addition, by using an OPO enriched fat as the carrier, the use of other vegetable oils as carriers can be avoided. This can be beneficial because many vegetable oils typically used in infant formula such as palm oil, coconut oil, palm kernel oil, soybean oil, sunflower oil and rapeseed oil can contain undesirable phytosterols. This provides a certain synergy with the delivery of the egg lecithin, which contains cholesterol, as the cholesterol content can be increased at the same time as reducing phytosterols that inhibit cholesterol absorption.

[0016] The process comprises mixing a dilute egg yolk lecithin solution from the extraction of an egg yolk material with the OPO triglyceride carrier. This provides an easily processed blend of egg yolk lecithin with the OPO triglyceride carrier directly from a dilute egg yolk lecithin-solvent extract solution, where removal of the liquid extractant leaves an easily handled blend of concentrated egg yolk lecithin with the OPO triglyceride carrier. As will be appreciated, egg lecithin can be defined as containing at least 60 wt.% phospholipids, for example comprising at least 60 wt.% acetone insolubles, and so while the OPO triglyceride-phospholipid concentrate contains egg yolk lecithin mixed with the carrier, the OPO triglyceride-phospholipid concentrate is not itself a lecithin. It will be appreciated that the phospholipids are insoluble in acetone, and so a lecithin comprising at least 60 wt.% phospholipids will also contain at least 60 wt.% acetone insolubles. The OPO triglyceride- phospholipid concentrate may also be referred to as comprising the OPO triglyceride carrier and egg phospholipids.

[0017] The egg lecithin is provided as a dilute egg yolk lecithin solution from the extraction of an egg yolk material with a liquid extractant, such as a solvent. It will be appreciated that the egg yolk lecithin solution may be provided from a separate extraction process and provided for mixing, or the process may comprise the step of extracting the egg yolk lecithin solution from an egg yolk material and providing the solution directly for mixing with the OPO triglyceride carrier. In preferred embodiments, providing the egg yolk lecithin solution comprises extracting from an egg yolk material with the liquid extractant and separating undissolved solids. Liquid extraction processes are generally known to the skilled person and the extraction from the egg yolk material may be performed in any suitable way. For example, the extraction may comprise mixing the egg yolk material with the liquid extractant, by high shear or low shear mixing for example, for a period of from 30 minutes to 3 hours, for example a period of from 1 hour to 2 hours. The undissolved solids may be removed in any suitable way, such as by centrifuge and / or by filtration. The concentration of egg yolk lecithin in the egg yolk lecithin solution following separation of solids may be determined by measuring the quantity of dry solids separated, and this concentration can be used to determine the mixing ratio with the triglyceride carrier. It will also be appreciated that an egg yolk lecithin solution that has been extracted separately to the present process and provided as a liquid extractant solution may be used in some embodiments.

[0018] The egg yolk material from which the egg yolk lecithin solution is extracted is preferably egg yolk powder. Egg yolk powder may be obtained in any suitable way and is well-known as an ingredient in the art, for example egg yolk powder may be obtained by spray drying egg yolk (typically pasteurised egg yolk).

[0019] The liquid extractant that forms the egg yolk lecithin solution (i.e. the liquid extractant used to extract from the egg yolk material) may be any suitable liquid that is capable of extracting an egg yolk lecithin, preferably an egg yolk lecithin having a phospholipid content of at least 60 wt.%, preferably 60 to 85 wt.%, for example from 65 to 80 wt.% or from 70 to 75 wt.%. Preferably, the liquid extractant comprises or consists essentially of ethanol and water. It has been found that the combination of ethanol and water can suitably provide a balance of extracting sufficiently pure phospholipids so to achieve a lecithin having greater than 60% acetone insolubles and / or at least 60 wt.% phospholipid content, whilst also providing an acceptable extraction yield. Water and ethanol as solvents are also more acceptable than other organic solvents for use in the food industry, and in particular infant formula where safety is of great significance. The ratio of water to ethanol is suitably selected so as to provide a lecithin having greater than 60% acetone insolubles and / or at least 60 wt.% phospholipid content. Preferably, the liquid extractant comprises or consists essentially of water and ethanol in a water: ethanol weight ratio of from 5:95 to 50:50, such as from 10:90 to 20:80.

[0020] The process comprises separating the liquid extractant from the mixture of egg yolk lecithin solution and OPO triglyceride carrier (that is, a mixture of liquid extractant such as solvent, OPO triglyceride carrier, and egg yolk lecithin). Typically, the liquid extractant is removed by evaporating the liquid extractant and it will be appreciated that removal of relatively volatile solvents by evaporation is known in the art. For example, the liquid extractant may be removed by evaporation under reduced pressure and / or elevated temperature, such as at a pressure of less than 400 mbar, for example less than 200 mbar, and / or at a temperature of from about 60 to about 100 °C, for example from about 70 to about 90 °C. For example, the liquid extractant may be removed under reduced pressure by evaporation in a rotary evaporator on a small scale. In general, any suitable evaporator known in the art may be used to remove the liquid extractant, for example a scraped surface evaporator, a film evaporator and the like. In some preferred embodiments, the liquid extractant may be removed by freeze drying.

[0021] The OPO triglyceride carrier is typically mixed with the egg yolk lecithin solution to provide a weight ratio of the OPO triglyceride carrier to the egg lecithin of from 1 :2 to 2: 1 , preferably from 1 :1.5 to 1.5:1 , for example from 1 :1.2 to 1.2:1. In preferred embodiments, the OPO triglyceride carrier is mixed with the egg yolk lecithin solution to provide a weight ratio of the triglyceride carrier to the egg lecithin of 1.0 or more, for example wherein the OPO triglyceride-phospholipid concentrate has an OPO triglyceride carrier to egg lecithin ratio of 1 .0 or more. The level of egg phospholipids in the triglyceride-phospholipid concentrate may, for example, be up to about 40 wt.%, preferably up to about 35 wt.%, such as from about 20 wt.% to about 40 wt.%, preferably from about 25 wt.% to about 35 wt.%. It has been found that large proportions of egg phospholipids in the triglyceride-phospholipid concentrate can lead to an undesired increase in phase separation.

[0022] The OPO triglyceride carrier comprising 1 ,3-dioleoyl-2-palmitoylglycerol (OPO) suitably has a ratio of palmitic acid in the 2-position of the triglycerides relative to the total palmitic acid in the triglycerides (SN2-C16:0) of at least 50 %, preferably from about 50 % to about 70 %, and a C52 triglyceride content of at least 42 wt.%, preferably up to about 60 wt.%, for example 42 wt.% to about 50 wt.%. The OPO triglyceride carrier may, for example, have a slip melting point of at least 30 °C, preferably at least 37 °C, where slip melting point may be measured by ISO 6321 :2021 .

[0023] The OPO triglyceride carrier may be provided from any suitable source. For example, the OPO triglyceride carrier may suitably be provided by structured triglycerides and it will be appreciated that OPO enriched structured fats are known to the skilled person and refer to triglyceride fats in which the fatty acids have been modified to add or remove particular fatty acids and / or to rearrange the positions of fatty acids in the triglyceride molecules. The OPO triglyceride carrier may in some instances comprise a synthetic triglyceride formed by adding oleic and palmitic acid to a glycerol backbone to produce a substantially pure OPO triglyceride. The OPO triglyceride carrier may be produced by any suitable process known in the art. Preferably, the OPO triglyceride carrier is produced by enzymatic interesterification of a triglyceride fat containing a significant proportion of triglycerides having palmitic acid in the 2-position, such as palm oil or a fraction thereof (such as palm stearin) with oleic acid. The OPO triglyceride carrier is preferably a triglyceride composition produced by enzymatic interesterification with oleic acid of a triglyceride mixture comprising a majority of triglycerides having palmitic acid in the 2-position, for example by enzymatic interesterification of palm stearin (or any other suitable triglyceride fat rich in tripalmitin, “PPP”).

[0024] By virtue of its chemical structure, OPO triglyceride, 1 ,3-dioleoyl-2-palmitoylglycerol, has a melting point that is higher than the majority of triglycerides that form liquid vegetable oils (and consequently these oils as a whole). The OPO triglyceride carrier therefore provides a carrier having a melting point above that of liquid vegetable oils that can be used as carriers or fillers in fat blends for infant formula. It has been found that this property of the OPO triglyceride carrier is beneficial in providing a substantially solid mixture with the egg lecithin at ambient temperature (for example at around 25 °C). When a mixture of OPO triglyceride carrier and egg lecithin is produced by evaporation of liquid extractant, the components typically form a substantially homogeneous mixture. However, where a liquid vegetable oil having a low melting point is used, it has been found that undesirable separation of the triglycerides and the phospholipids occurs, which can lead to problems of dosing accurately from the mixture into a fat blend without additional steps to ensure a homogeneous mixture. The higher melting point of the OPO triglyceride carrier leads to the formation of a substantially solid mixture with egg lecithin at ambient temperatures. This property of the OPO triglyceride-phospholipid concentrate according to the present process can help to avoid separation of the triglycerides from the phospholipids during storage and transport. This is particularly beneficial for the production of a fat blend for infant formula, because the OPO triglyceride carrier not only addresses handling issues, but also contributes positively to the overall triglyceride profile of a fat blend in terms of its absorbability for infants.

[0025] In preferred embodiments, the process further comprises the step of packaging the OPO triglyceride-phospholipid concentrate in a container. This may be any suitable container that may, for example, be used to store the OPO triglyceride-phospholipid concentrate and to transport it from a location in which the OPO triglyceride-phospholipid concentrate is produced to a second location where a fat blend and / or an infant formula comprising the fat blend is produced.

[0026] As will be appreciated, in a fat blend for an infant formula, it may be beneficial to include a substantial portion of OPO triglycerides in addition to those provided by the OPO triglyceride-phospholipid concentrate. Thus, in preferred embodiments the process may further comprise blending the OPO triglyceride-phospholipid concentrate with additional OPO-containing fats. For example, the additional OPO-containing fats may be the same or a similar fat to that used as the OPO triglyceride carrier, for example it may comprise an OPO-containing fat having a ratio of palmitic acid in the 2-position of the triglycerides relative to the total palmitic acid in the triglycerides (SN2-C16:0) of at least 50%, and a C52 triglyceride content of at least 42 wt.% as described previously herein. In this way, a fat composition comprising the OPO triglyceride-phospholipid concentrate and additional OPO-containing fat may provide a single source of egg phospholipids and OPO for addition to fat blends for infant formula. Furthermore, in some instances, this may form a fat composition that does not require blending with other fats such as natural vegetable oils, prior to its use in preparing an infant formula.

[0027] A further aspect provides an OPO triglyceride-phospholipid concentrate comprising a mixture of:

[0028] (i) an egg yolk lecithin obtained by extraction of an egg yolk material with a liquid extractant; and

[0029] (ii) an OPO triglyceride carrier comprising 1 ,3-dioleoyl-2-palmitoylglycerol and having a ratio of palmitic acid in the 2-position of the triglycerides relative to the total palmitic acid in the triglycerides (SN2-C16:0) of at least 50%, and a C52 triglyceride content of at least 42 wt.%; wherein the weight ratio of (i) to (ii) in the concentrate is from 1 :2 to 2:1 .

[0030] As will be appreciated, the OPO triglyceride-phospholipid concentrate, the components thereof, and its process of production may be substantially as defined elsewhere herein. For example, the egg yolk lecithin is preferably an egg yolk lecithin extracted from egg yolk powder using a mixture of water and ethanol as described herein. It will be appreciated that the liquid extractant that was used in the extraction of the egg yolk lecithin in part (i) is substantially absent from the OPO triglyceride-phospholipid concentrate, for example the OPO triglyceride-phospholipid concentrate may contain less than 5 wt.% of the liquid extractant, preferably less than 2 wt.% of the liquid extractant, for example less than 1 wt.% of the liquid extractant, such as less than 0.5 wt.% of the liquid extractant. Where liquid extractant comprising ethanol and water is not completely removed, it will be appreciated that the OPO triglyceride-phospholipid concentrate will be substantially free of ethanol, but may in some instances contain small amounts of residual water.

[0031] As has been described previously, a triglyceride-phospholipid concentrate formulated in this way has the benefit of providing enhanced resistance to separation during storage, and can be advantageously produced without requiring the isolation of egg lecithin that can itself be difficult to handle.

[0032] A further aspect provides a process for preparing a fat blend for an infant formula comprising: providing a triglyceride-phospholipid concentrate comprising a mixture of a triglyceride carrier and egg yolk lecithin; mixing the triglyceride-phospholipid concentrate with a triglyceride composition comprising 1 ,3-dioleoyl-2-palmitoylglycerol (OPO), and optionally one or more vegetable oils, to form the fat blend; wherein the ratio of the triglyceride composition comprising OPO to the one or more vegetable oils is controlled to provide a ratio of palmitic acid in the 2-position of the triglycerides relative to the total palmitic acid in the triglycerides (SN2-C16:0) of at least 40%; and wherein the proportion of the triglyceride-phospholipid concentrate is controlled to provide a cholesterol content in the fat blend of from 140 to 360 mg / 100g.

[0033] As will be appreciated, the triglyceride-phospholipid concentrate, the additional triglyceride composition comprising OPO, and any other components of the fat blend may suitably be as described elsewhere herein and / or produced by the processes described herein.

[0034] The vegetable oils optionally included in the fat blend may comprise any suitable oils and preferably comprise rapeseed oil and / or sunflower oil at least a portion of which may be high oleic sunflower oil. In some preferred embodiments, the vegetable oils may comprise rapeseed oil, sunflower oil, and high oleic sunflower oil, or mixtures thereof. The vegetable oils may be added so as to provide linoleic acid (C18:2) in the fat blend in an amount of from 10 wt.% to 20 wt.%, preferably from 12 wt.% to 18 wt.%, for example from 14 wt.% to 16 wt.%, and to provide linolenic acid (C18:3) in the fat blend in an amount of from 0.5 wt.% to 3.0 wt.%, preferably from 1 .0 wt.% to 2.0 wt.%, for example from 1 .2 wt.% to 1.6 wt.%. By way of example, rapeseed oil may be added to enrich linolenic acid (C18:3) content and sunflower oil may be added to enrich linoleic acid (C18:2) content in the fat blend. The vegetable oils may comprise up to about 50 wt.% of the fat blend, preferably no more than about 45 wt.%.

[0035] The proportion of the triglyceride-phospholipid concentrate is controlled to provide a cholesterol content in the fat blend of from 140 to 360 mg / 100g. In some preferred embodiments, the proportion of the triglyceride-phospholipid concentrate is controlled to provide a cholesterol content in the fat blend of from 170 to 360 mg / 100g, for example from 240 to 350 mg / 100g, such as from 270 to 340 mg / 100g. It has been found that by controlling the quantity of the triglyceride-phospholipid concentrate in the fat blend to give a cholesterol content that advantageously mimics human milk, other advantageous nutritional components such as phospholipids like phosphatidylcholine and sphingomyelin, and phospholipid-bound DHA (docosahexaenoic acid) and ARA (arachidonic acid), may simultaneously be provided in the fat blend at advantageous levels. Controlling cholesterol by addition of the OPO triglyceride-phospholipid concentrate, allows for a reduction in the amount of milk fat whilst maintaining optimal cholesterol content, which as a result permits the use of additional OPO containing fat in place of milk fat, that provides an improved triglyceride profile. When producing an infant formula, it is generally desirable to control the various components to provide an overall formulation that is close to, and retains the beneficial nutritional properties of, natural human milk. However, due to the necessity to form infant formula from a combination of different ingredients that are commercially available, it is difficult to reproduce all beneficial aspects of natural human milk in an economically viable way. Therefore, typically, when formulating an infant formula, it is necessary to compromise on some nutritional components in order to focus on others. There is therefore a decision that needs to be made as to how to formulate an array of different components and which nutritional factors to focus on. The present inventors have appreciated that by using a triglyceride-phospholipid concentrate, and by adding this in an amount to provide a desirable level of cholesterol, this advantageously permits other nutritional needs to be conveniently met.

[0036] The fat blend may have a palmitic acid content of from 16 wt.% to 30 wt.% as a proportion of the total fatty acids, preferably from 18 wt.% to 25 wt.%; and / or the fat blend may have a linoleic acid content of from 10 wt.% to 20 wt.% as a proportion of the total fatty acids.

[0037] Preferably, the total phospholipid content in the fat blend is at least 1 .3 wt.%, preferably at least 1.5 wt.%, for example at least 2.0 wt.%, which may include at least about 1.0 wt.% phosphatidyl choline, preferably at least 1.2 wt.%, for example at least 1.4 wt.%, and at least 0.10 wt.% sphingomyelin, preferably at least 0.14 wt.%. For example, the phospholipids may preferably include at least about 50 wt.% phosphatidyl choline, preferably at least about 60 wt.%, for example at least 70 wt.% phosphatidyl choline, and / or at least about 3 wt.% sphingomyelin, for example at least about 4 wt.% sphingomyelin, as a proportion of the total phospholipids. The phospholipids in the fat blend may preferably include, as a proportion of the total phospholipids, from 50 wt.% to 90 wt.% phosphatidyl choline, preferably from 60 wt.% to 80 wt.% phosphatidyl choline and / or the phospholipids in the fat blend may preferably include from 3 wt.% to 9 wt.% sphingomyelin, preferably from 4 wt.% to 8 wt.% sphingomyelin.

[0038] The fat blend may comprise at least 0.05 g / 100g of phospholipid-bound ARA (arachidonic acid) and at least 0.03 g / 100g of phospholipid-bound DHA (docosahexaenoic acid), for example the fat blend may comprise from 0.05 to 0.20 g / 100g, preferably from 0.06 to 0.16 g / 100g, for example from 0.07 to 0.12 g / 100g of phospholipid-bound ARA, and / or the fat blend may comprise from 0.03 to 0.20 g / 100g, preferably from 0.04 to 0.15 g / 100g, for example from 0.06 to 0.12 g / 100g of phospholipid-bound DHA.

[0039] The fat blend of the invention may comprise milk fat in an amount of no more than 15 wt.%. It is preferred to limit the proportion of milk fat in the fat blend and in some embodiments the fat blend does not contain milk fat. This can advantageously permit an increased proportion of OPO-containing fat to be used, providing an improved triglyceride profile.

[0040] A further aspect provides a fat blend for an infant formula formed from a mixture of:

[0041] A triglyceride-phospholipid concentrate comprising a mixture of a triglyceride composition and egg yolk lecithin; and a triglyceride composition comprising 1 ,3-dioleoyl-2-palmitoylglycerol (OPO) and optionally one or more vegetable oils; wherein the triglycerides in the fat blend have a ratio of palmitic acid in the 2- position of the triglycerides relative to the total palmitic acid in the triglycerides (SN2-C16:0) of at least 40%; and wherein the fat blend has a cholesterol content of from 140 to 360 mg / 100g.

[0042] It will be appreciated that the fat blend and its components may be as defined elsewhere herein, and the fat blend and its components may suitably be produced by the processes defined herein.

[0043] A further aspect provides an infant formula powder comprising a fat blend as defined herein and / or an OPO triglyceride-phospholipid concentrate as defined herein. Preferably, the infant formula composition comprises from 20 to 40 wt.% total fat (which may for example comprise or consist essentially of a fat blend as defined herein), more preferably from 25 wt.% to 30 wt.%, for example from 26 wt.% to 28 wt.%.

[0044] Infant formula may have any suitable formulation in addition to the fat component (though it will be appreciated that aspects of the formulation are limited by regulation in many territories), and will typically comprise a fat component together with other components such as lactose, skimmed milk powder and whey powder. Thus, in preferred embodiments, the composition comprises a fat blend as defined herein, lactose, skimmed milk powder and whey powder. The infant formula may suitably comprise from 20 to 40 wt.% of the fat blend, from 50 to 55 wt.% of lactose, from 10 to 20 wt.% skimmed milk powder and from 5 to 10 wt.% whey powder. The whey powder suitably comprises whey protein and casein, preferably in a whey:casein weight ratio of from 50:50 to 60:40. It will be appreciated that whey powder may also comprise phospholipids that are beneficial for infant formula, however it is not possible to add sufficient phospholipids from whey whilst avoiding an undesirable imbalance of the whey:casein ratio or excluding other necessary components in the formula.

[0045] As will be appreciated, a fat blend as defined herein can provide an advantageous balance of cholesterol content with other nutritional components. Preferably, the infant formula has a cholesterol content of from 30 to 100 mg / 100g, preferably 40 to 100 mg / 100g, for example 50 to 100 mg / 100g, and / or a phospholipid content of at least 0.5 wt.%, preferably at least 0.6 wt.%, for example at least 0.9 wt.%. The phospholipids may include at least about 50 wt.% phosphatidyl choline, preferably at least about 60 wt.%, for example at least 70 wt.% phosphatidyl choline, and / or at least about 3 wt.% sphingomyelin, for example at least about 4 wt.% sphingomyelin, as a proportion of the total phospholipids. The phospholipids in the fat blend may preferably include, as a proportion of the total phospholipids, from 50 wt.% to 90 wt.% phosphatidyl choline, preferably from 60 wt.% to 80 wt.% phosphatidyl choline and / or the phospholipids in the fat blend may preferably include from 3 wt.% to 9 wt.% sphingomyelin, preferably from 4 wt.% to 8 wt.% sphingomyelin. The formula may also comprise at least 0.02 g / 100g of phospholipid-bound ARA (arachidonic acid) and at least 0.01 g / 100g of phospholipid-bound DHA (docosahexaenoic acid), for example the formula may comprise from 0.01 to 0.10 g / 100g, preferably from 0.02 to 0.07 g / 100g, for example from 0.03 to 0.05 g / 100g of phospholipid-bound ARA and / or the formula may comprise from 0.01 to 0.05 g / 100g, preferably from 0.02 to 0.04 g / 100g, for example at least 0.03 g / 100g of phospholipidbound DHA.

[0046] The invention will now be described by reference to the following non-limiting Examples.

[0047] Examples In the following examples, the OPO containing fat is a fat produced by enzymatic transesterification of palm stearin having the triglyceride composition set out in Table 1. The fatty acids are measured at wt% of the total fatty acids, using a FAME method in accordance with standard method NEN 12966-2. Table 1 : FAME of OPO fat Production of triglyceride-phospholipid concentrates

[0048] Egg yolk powder (250g) was mixed with 825g of a liquid extractant comprising 85 wt.% ethanol and 15 wt.% water. This was mixed for 1 hour and 30 minutes at 25 to 30 °C, and then centrifuged for 10 minutes at 3450 rpm, and filtered through filter paper (MN615).

[0049] The egg yolk was selected for containing phospholipid-bound DHA and phospholipidbound ARA, and was obtained from AAK AB, Sweden.

[0050] The dry matter removed from the liquids was weighed to calculate the quantity of lecithin remaining in the solution to allow the addition of fat in the desired ratio in the range of phospholipids to triglyceride carrier fat from 1 :2 to 2:1.

[0051] The filtrate was split into two portions of approximately 350g each. High oleic sunflower oil (17.5g) was added to a first portion, and OPO fat (T able 1 , 17.5g) was added to the second portion. The ratio of egg yolk lecithin and OPO triglyceride was approximately 1 :1.

[0052] The solvent was evaporated from each sample on a BUCH I rotary evaporator at 80 °C, 160 rpm and 150 mbar.

[0053] The used lecithin phospholipids in the triglyceride-phospholipid concentrate in this example are derived from eggs, but could be replaced with similar phospholipids derived from other sources, such as plant-based lecithins or microbial lecithins, for instance derived from bacteria, funghi, algae or yeast, provided that these would also contain significant amounts of phospholipid-bound arachidonic acid and phospholipid-bound docosahexaenoic acid.

[0054] Table 2 describes the phospholipid composition of the triglyceride-phospholipid concentrate, and table 3 describes the fatty acid composition. The phospholipids profile of the triglyceride-phospholipid concentrate was determined using quantitative31P phosphorus NMR, by Spectral Service, Emil-Hoffmann-StraBe 33D- 50996, Kdln, using method SAA-MET002-04. The fatty acid profile (FAME) was measured in accordance to ISO 21966-1 .

[0055] Table 2: phospholipid composition of the triglyceride-phospholipid concentrate.

[0056] Although the most abundant phospholipid-bound fatty acids in the triglyceride- phospholipid blend are C16 and C18:1 from OPO triglyceride, note the presence of significant amounts of phospholipid-bound arachidonic acid and phospholipid-bound docosahexaenoic acid.

[0057] Table 3: Fatty Acid Composition (FAME) of triglyceride-phospholipid concentrate (ISO

[0058] 21966-1)

[0059] Stability test

[0060] A triglyceride-phospholipid concentrate using OPO as the triglyceride, as described above was compared for stability with the same blend but using high oleic sunflower oil (HOSO) instead of OPO.

[0061] The samples were stored for 1 week at 22°C, 4 weeks at 22°C and another 4 weeks at 25°C.

[0062] For the Comparative Example using high oleic sunflower oil, separation of the oil from the phospholipids was observed at 22 °C, with increasing liquid content to a temperature of 25 °C. In contrast, for the Example in accordance with the invention using the OPO structured fat, the mixture was observed to remain solid without separation at temperatures up to 25 °C. Thus, by providing a triglyceride-phospholipid concentrate using an OPO structured fat, the ease of handling and storage stability is improved compared to HOSO.

[0063] The triglyceride-phospholipid concentrate using OPO can be easily mixed with other fats as the fat component for infant formula, for instance with OPO. In OPO-based infant formula, the triglyceride-phospholipid concentrate using OPO has the advantage over triglyceride-phospholipid concentrate using vegetable oils (sunflower oil, high oleic sunflower oil, rapeseed oil) that the desired fatty acid profile does not need to be corrected for the presence of disturbing fatty acids in the vegetable oil, such as for instance additional C18:1 in HOSO. For the most convenient blending, the infant formula should use the same OPO fat as the OPO that was used in preparing the triglyceride-phospholipid concentrate.

[0064] Preparation of fat blends and infant formula

[0065] Fat blends were prepared comprising vegetable oils (sunflower oil, high oleic sunflower oil rapeseed oil), , with or without milk fat or OPO fat (Table 4), with soy lecithin or a triglyceride-phospholipid concentrate. These fat blends were combined with skim milk powder, whey powder (comprising 60:40 whey:casein) and lactose to produce an infant formula powder. Note that the soy lecithin, used in the comparative example, does not contain phospholipid-bound arachidonic acid and phospholipid-bound docosahexaenoic acid.

[0066] The composition and recipe for the samples is shown in Table 4, together with values for a typical natural human milk. “PC” refers to phosphatidylcholine and “SM” refers to sphingomyelin. Cholesterol levels were determined using GC / MS. Other components were determined by the methods mentioned above.

[0067] As can be seen, where a triglyceride-phospholipid concentrate (specifically a triglyceride:egg lecithin concentrate) is used, this allows the milk fat content to be reduced or eliminated. This permits a cholesterol content in the formula that is comparative to natural human milk, whilst also maintaining the required level of palmitic acid in the 2- position of the triglycerides (SN2:C16). It will be appreciated that, while human milk typically has SN2:C16 above 70%, the absorption benefits in an infant formula may be obtained for a fat having SN2:C16 of greater than 40%. In addition, beneficial levels of phospholipids and phospholipid-bound DHA and ARA are simultaneously provided by such formulations. In this way, formulations according to the present invention can provide an advantageous balance of the desired nutritional components for an infant formula.

Claims

CLAIMS:1 . A process for producing a triglyceride-phospholipid concentrate comprising: providing an egg yolk lecithin solution from the extraction of an egg yolk material with a liquid extractant; mixing the egg yolk lecithin solution with an OPO triglyceride carrier comprising 1 ,3- dioleoyl-2-palmitoylglycerol and having a ratio of palmitic acid in the 2-position of the triglycerides relative to the total palmitic acid in the triglycerides (SN2-C16:0) of at least 50%, and a C52 triglyceride content of at least 42 wt.%; separating the liquid extractant from the mixture to produce a triglyceride- phospholipid concentrate comprising the OPO triglyceride carrier and egg lecithin.

2. A process according to Claim 1 , wherein providing the egg yolk lecithin solution comprises extracting from an egg yolk material with the liquid extractant and separating undissolved solids.

3. A process according to Claim 1 or Claim 2, wherein the liquid extractant comprises or consists essentially of water and ethanol, for example water and ethanol in a ratio of from 5:95 to 50:50, such as from 10:90 to 20:80.

4. A process according to any one of the preceding claims, wherein separating the liquid extractant from the mixture comprises evaporating the liquid extractant.

5. A process according to any one of the preceding claims, wherein the liquid extractant is separated from the mixture by freeze drying.

6. A process according to any one of the preceding claims, wherein the OPO triglyceride carrier is mixed with the egg yolk lecithin solution to provide a weight ratio of the triglyceride carrier to the egg lecithin of from 1 :2 to 2:1 , preferably from 1 :1.5 to 1.5:1 , for example from 1 :1.2 to 1.2:1.

7. A process according to any one of the preceding claims, further comprising the step of packaging the OPO triglyceride-phospholipid concentrate in a container.

8. A process according to any one of the preceding claims, wherein the OPO triglyceride carrier is a triglyceride composition produced by enzymatic interesterification with oleic acid of a triglyceride mixture comprising a majority of triglycerides having palmitic acid in the 2-position, for example by enzymatic interesterification of palm stearin.

9. A process according to any one of the preceding claims, wherein the egg yolk material is egg yolk powder.

10. A process according to any one of the preceding claims, further comprising blending the OPO triglyceride-phospholipid concentrate with additional OPO-containing fat.

11. An OPO triglyceride-phospholipid concentrate comprising a mixture of:(i) an egg yolk lecithin obtained by extraction of an egg yolk material with a liquid extractant; and(ii) an OPO triglyceride carrier comprising 1 ,3-dioleoyl-2-palmitoylglycerol and having a ratio of palmitic acid in the 2-position of the triglycerides relative to the total palmitic acid in the triglycerides (SN2-C16:0) of at least 50%, and a C52 triglyceride content of at least 42 wt.%; wherein the weight ratio of (i) to (ii) in the concentrate is from 1 :2 to 2:1 .

12. A process for preparing a fat blend for an infant formula comprising: providing a triglyceride-phospholipid concentrate comprising a mixture of a triglyceride carrier and egg yolk lecithin; mixing the triglyceride-phospholipid concentrate with a triglyceride composition comprising 1 ,3-dioleoyl-2-palmitoylglycerol (OPO), and optionally one or more vegetable oils, to form the fat blend; wherein the ratio of the triglyceride composition comprising OPO to the one or more vegetable oils is controlled to provide a ratio of palmitic acid in the 2-position of the triglycerides relative to the total palmitic acid in the triglycerides (SN2-C16:0) of at least 40%; and wherein the proportion of the triglyceride-phospholipid concentrate is controlled toprovide a cholesterol content in the fat blend of from 140 to 360 mg / 100g.

13. A process according to Claim 12, wherein the triglyceride-phospholipid concentrate is produced by the process of any one of Claims 1 to 10 and / or the triglyceride- phospholipid concentrate is as defined in Claim 11.

14. A process according to Claim 12 or Claim 13, wherein the fat blend has a palmitic acid content of from 16 wt.% to 30 wt.% as a proportion of the total fatty acids, preferably from 18 wt.% to 25 wt.%; and / or wherein the fat blend has a linoleic acid content of from 10 wt.% to 20 wt.% as a proportion of the total fatty acids.

15. A process according to any one of Claims 12 to 14, wherein the fat blend has a phospholipid content of at least 1 .5 wt.%.

16. A process according to any one of Claims 12 to 15, wherein the fat blend comprises from 0.05 to 0.20 g / 100g, preferably from 0.06 to 0.16 g / 100g, for example from 0.07 to 0.12 g / 100g of phospholipid-bound arachidonic acid; and / or the fat blend comprises from 0.03 to 0.20 g / 100g, preferably from 0.04 to 0.15 g / 100g, for example from 0.06 to 0.12 g / 100g of phospholipid-bound docosahexaenoic acid17. A process according to any one of Claims 12 to 16, wherein the fat blend comprises milk fat in an amount of no more than 15 wt.%.

18. A fat blend for an infant formula formed from a mixture of: a triglyceride-phospholipid concentrate comprising a mixture of a triglyceride composition and egg yolk lecithin; a triglyceride composition comprising 1 ,3-dioleoyl-2-palmitoylglycerol (OPO), and optionally one or more vegetable oils; wherein the triglycerides in the fat blend have a ratio of palmitic acid in the 2- position of the triglycerides relative to the total palmitic acid in the triglycerides (SN2-C16:0) of at least 40%; and wherein the fat blend has a cholesterol content of from 140 to 360 mg / 100g.

19. A fat blend according to Claim 18, wherein the fat blend is produced by the process of any one of claims 12 to 17, and / or wherein the fat blend is as defined in any one of Claims 14 to 17.

20. An infant formula powder composition comprising the fat blend of Claim 18 or 19 or an OPO triglyceride-phospholipid concentrate according to Claim 11.

21. An infant formula powder composition according to Claim 20, wherein the infant formula composition comprises from 20 to 40 wt.% total fat, preferably from 25 wt.% to 30 wt.%, for example from 26 wt.% to 28 wt.%.

22. An infant formula powder composition according to Claim 20 or Claim 21 , wherein the composition comprises a fat blend according to Claim 18, lactose, skimmed milk powder and whey powder comprising whey protein and casein.

23. An infant formula powder composition according to Claim 22, comprising from 25 to 30 wt.% of the fat blend, from 50 to 55 wt.% of lactose, from 10 to 20 wt.% skimmed milk powder and from 5 to 10 wt.% whey powder, preferably comprising whey protein and casein in a whey:casein ratio of from 50:50 to 60:40.

24. An infant formula powder composition according to any one of Claims 20 to 23, wherein the formula has a cholesterol content of from 30 to 100 mg / IOOg and a phospholipid content of at least 0.5 wt.%, preferably including at least about 50 wt.% phosphatidyl choline and at least about 3 wt.% sphingomyelin, as a proportion of the total phospholipids.

25. An infant formula powder composition according to any one of Claims 20 to 24, wherein the formula comprises from 0.01 to 0.10 g / 100g, preferably from 0.02 to 0.07 g / 100g, for example from 0.03 to 0.05 g / 100g of phospholipid-bound arachidonic acid and / or the formula may comprise from 0.01 to 0.05 g / 100g, preferably from 0.02 to 0.04 g / 100g, for example at least 0.03 g / 100g of phospholipid-bound docosahexaenoic acid.

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