Patent Description:
A single emulsion is a composition containing a stable mixture of two immiscible phases, in which droplets of one phase are dispersed throughout the other phase. Typical examples of a single emulsion include a water-in-oil (W/O) emulsion and an O/W emulsion.

In the case of a W/O emulsion, a certain content of an aqueous phase (W), e.g. pure water or an aqueous solution, in a form of droplets is uniformly dispersed throughout a lipid content (O), that forms a continuous lipid phase. Lipids, also referred to herein as oils, may include waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E, and K), monoglycerides, diglycerides, triglycerides, phospholipids, fats and others. Examples of lipids suitable for use in the W/O emulsions are disclosed in <CIT> and include vegetable or animal derived oils, the content thereof varying from <NUM> to <NUM> wt%. Single W/O emulsions where the lipid is a fat are typically used to manufacture various food products such as spreads, e.g. margarine.

Single W/O or O/W emulsions can also be used as precursors to prepare double emulsions, e.g. water-in-oil-in-water (W/O/W) emulsions. W/O/W emulsions, also commonly referred to as double emulsions, water-in-oil-in-water double emulsions, or multiple emulsions, are emulsion systems where small water droplets are entrapped within larger oil droplets that in turn are dispersed in a continuous water phase. The advantage of double emulsions is widely recognized in fields as diverse as pharmaceuticals, cosmetics, pest and disease control, food, feed and coatings of the paint type. W/O/W emulsions allow in particular the encapsulation of various active substances in the internal, i.e. inside the oil phase, aqueous phase.

Double emulsions are generally prepared using a <NUM>-step procedure. For W/O/W emulsions, first, a water-in-oil (W/O) emulsion is formed by blending a first (internal) aqueous phase (W<NUM>) and an oil phase (O) together in the presence of a suitable oil-soluble (e.g. low hydrophilic-lipophilic balance (HLB) number) emulsifier. This emulsifier adsorbs to the surface of the water droplets and forms a protective coating that reduces and/or prevents undesirable coalescence thereof. Furthermore, the oil-soluble emulsifier reduces the interfacial tension between the oil and the water phase, favoring the formation of droplets, and increasing the stability of emulsions. Second, a W/O/W emulsion is formed by blending the W/O emulsion with a second (external) aqueous phase (W<NUM>) containing a suitable water-soluble (e.g. high HLB number) emulsifier. This emulsifier adsorbs to the surface of the oil droplets and forms a protective coating that reduces and/or prevents their subsequent coalescence. The water-soluble emulsifier also reduces the interfacial tension between the water and the oil phase, favoring the formation of droplets, and increasing the stability of the double emulsion. The first step is usually carried out in a high-shear device to produce very fine droplets of water in a continuous lipid. The second emulsification step is typically carried out in a low-shear device to avoid rupturing the multiple droplets. <CIT> relates to a multiple emulsion of the W/O/W type for stabilization of natural coloring agents against changes in pH values, oxidation and light as well as ingredient interactions. Other methods of manufacturing emulsions can be found in <CIT>; <CIT>; <CIT>; <CIT> and <CIT>.

Lecithins, in particular those referred to as low-HLB emulsifiers (typically having an HLB below <NUM>), are widely used to produce W/O emulsions but less used in the manufacturing of double emulsions and in particular of W/O/W emulsions. Lecithin is a naturally occurring compound and is a generic term used to designate a mixture of (glycero)phospholipids including inter alia phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and phosphatidic acid. Lecithin may be in a form of a liquid in which case the phospholipids are typically dissolved in an oil phase; or it may be in a form of a powder. Since up to date, powerful emulsifiers are used to stabilize W/O/W emulsions, it would be desirable to provide a way of manufacturing stable emulsions using the naturally occurring lecithin. Also it would be highly desirable to increase the water content of the oil droplets of the W/O/W emulsion, which in turn may be used to produce products having a low fat content as well as other advantageous properties.

An object of the present invention may therefore be to provide a W/O/W emulsion comprising lecithin, in particular a low-fat W/O/W emulsion, having optimum stability at low and ambient temperatures and preferably having an increased content of the internal aqueous phase.

It has been surprisingly found that one or more of the objectives indicated above may be achieved with a water-in-oil-in-water (W<NUM>/O/W<NUM>) emulsion comprising a lipid phase (O) and a water phase (W<NUM>), the lipid phase being distributed inside the water phase, wherein the lipid phase contains a plurality of water droplets (W<NUM>), wherein the water content inside the lipid phase is between <NUM> wt% and <NUM> wt% relative to the total weight of the lipid phase, wherein the water droplets are stabilized inside the lipid phase by an emulsifier composition, wherein the emulsifier composition comprises an Acetone-insoluble (AI) component containing a Phosphatidyl Choline (PC), a Phosphatidyl Inositol (PI), a Phosphatidyl Ethanolamine (PE) and a Phosphatidic Acid (PA), wherein PC is in an amount of at most <NUM>% relative to the total weight of the emulsifier composition and wherein the emulsifier composition is characterized by a phospholipid weight ratio R of at most <NUM>%, the ratio R being defined according to Formula <NUM>: <MAT> wherein PC+PI+PE+PA is the sum of the individual weights of the respective constituents of the AI component and AI is the total weight of the AI component, and wherein the water droplets (W1) have an average combined volume of at least <NUM>% of the volume of the liquid droplet containing said water droplets and wherein the lipid phase is stabilised inside the water phase by a second emulsifier composition, wherein the second emulsifier composition is carboxymethyl cellulose (CMC).

The inventors observed that the inventive emulsion has an optimum balance between emulsion stability and fat content. Moreover, when used in the manufacturing of various products, it provides said products with excellent properties. The inventors also observed that while being optimally stable, when used in manufacturing food products the inventive emulsion may provide said products with an agreeable mouthfeel.

The invention relates to a water-in-oil-in-water (W<NUM>/O/W<NUM>) emulsion (hereinafter "the inventive emulsion") comprising a lipid phase (O) and a water phase (W<NUM>), the lipid phase being distributed inside the water phase, wherein the lipid phase contains a plurality of water droplets (W<NUM>). The water inside the lipid phase is in the form of droplets and in a content of between <NUM> wt% and <NUM> wt% relative to the total weight of the lipid phase.

The water droplets are stabilized inside the lipid phase by an emulsifier composition, which comprises an Acetone-insoluble (AI) component containing a Phosphatidyl Choline (PC), a Phosphatidyl Inositol (PI), a Phosphatidyl Ethanolamine (PE) and a Phosphatidic Acid (PA), wherein PC is in an amount of at most <NUM>% relative to the total weight of the emulsifier composition and wherein the emulsifier composition is characterized by a phospholipid weight ratio R of at most <NUM>%, the ratio R being defined according to Formula <NUM>: <MAT> wherein PC+PI+PE+PA is the sum of the individual weights of the respective constituents of the AI component and AI is the total weight of the AI component.

The emulsifier composition used in accordance with the invention comprises an Acetone-Insoluble (AI) component, which is understood as the component comprising a group of constituents obtained upon mixing the emulsifier composition with acetone, decanting and extracting the acetone in accordance with the method presented herein below in the "Methods for measurement" section. Preferably the AI component is in a weight ratio of at least <NUM>% relative to the total weight of the emulsifier composition, more preferably at least <NUM>%, most preferably at least <NUM>%. Preferably, the AI is at most <NUM>%, more preferably at most <NUM>%. Preferably, the AI component is between <NUM> and <NUM> wt% of the total weight of the emulsifier composition.

As used herein, PC, PA, PE and PI are constituents of the emulsifier composition, which are insoluble in acetone and may be commonly referred to as phospholipid fractions. It is herein understood that the individual phospholipid fractions may contain modified and non-modified fractions. Examples of modified phospholipid fractions include hydrolyzed PC, PA, PE and PI, hereinafter denoted as L-PC, L-PA, L-PE and L-PI, respectively. Preferably, the emulsifier composition used in accordance with the invention contains modified phospholipid fractions in a total amount of less than <NUM> wt%, more preferably less than <NUM> wt% relative to their non-modified counterparts.

Preferably, the characteristic ratio R of the emulsifier composition contained by the inventive emulsion is at most <NUM>%, more preferably at most <NUM>%, most preferably at most <NUM>%. Preferably, R is between <NUM>% and <NUM>%, more preferably between <NUM>% and <NUM>%, most preferably between <NUM>% and <NUM>%.

Preferably, the amount of PC in the emulsifier composition contained by the inventive emulsion is at most <NUM>%, more preferably at most <NUM>%, even more preferably at most <NUM>%, most preferably at most <NUM>%. Preferably, said amount of PC is at least <NUM>%, more preferably at least <NUM>%, even more preferably at least <NUM>%, most preferably at least <NUM>%. Preferably the amount of PC is between <NUM>% and <NUM>%, more preferably between <NUM>% and <NUM>%, most preferably between <NUM>% and <NUM>%.

Preferably, the PA in the emulsifier composition is in an amount of at most <NUM> %, more preferably at most <NUM>%, even more preferably at most <NUM>%, yet even more preferably at most <NUM>%, yet even more preferably at most <NUM>%, most preferably at most <NUM>% relative to the total weight of the emulsifier composition. Preferably, said amount of PA is at least <NUM>%, more preferably at least <NUM>%, even more preferably at least <NUM>%, most preferably at least <NUM>%.

Preferably, the PE in the emulsifier composition is in an amount of at most <NUM>%, more preferably at most <NUM>%, even more preferably at most <NUM>%, yet even more preferably at most <NUM>%, most preferably at most <NUM>% relative to the total weight of the emulsifier composition. Preferably, said amount of PE is at least <NUM>%, more preferably at least <NUM>%, even more preferably at least <NUM>%, most preferably at least <NUM>%.

Preferably, the emulsifier composition used in accordance with the invention has a ratio P<NUM>:P<NUM> of from <NUM>:<NUM> to <NUM>:<NUM>; wherein P<NUM> is defined as the weight ratio of phospholipid components according to Formula <NUM>: <MAT> and P<NUM> is defined as the weight ratio of phospholipid components according to Formula <NUM>: <MAT>.

Preferably, P<NUM> is in the range of from <NUM> to <NUM>; more preferably in the range from <NUM> to <NUM>; most preferably in the range from <NUM> to <NUM>. Preferably, P<NUM> is in the range of from <NUM> to <NUM>; more preferably in the range from <NUM> to <NUM>; most preferably in the range from <NUM> to <NUM>. In one embodiment, the emulsifier composition used according to present invention preferably has a phospholipid P<NUM> value in the range of from <NUM> to <NUM> and a P<NUM> value in the range of from <NUM> to <NUM>; most preferably in the range from <NUM> to <NUM>. It was observed that for such values of P<NUM> and P<NUM>, the emulsifying composition had a high emulsifying capacity, with good stabilising properties.

Preferably, the emulsifier composition used in accordance with the invention has a ratio P<NUM> of at most <NUM>, more preferably at most <NUM>, most preferably at most <NUM>, wherein P<NUM> is defined according to Formula <NUM>: <MAT>.

Preferably, the ratio P<NUM> is at least <NUM>, more preferably at least <NUM>, most preferably at least <NUM>. Preferably, P<NUM> is between <NUM> and <NUM>, more preferably between <NUM> and <NUM>, even more preferably between <NUM> and <NUM>.

The emulsifier composition used in accordance with the invention stabilizes the inventive emulsion and may influence its organoleptic properties. The amount of emulsifier composition is preferably at least <NUM> wt% based on the total weight of the emulsion, more preferably at least <NUM> wt%, most preferably at least <NUM> wt%. Said amount is preferably at most <NUM> wt%, more preferably at most <NUM> wt%, most preferably at most <NUM> wt%.

Preferably, the amount of emulsifier composition is at least <NUM> wt% relative to the amount of the lipid phase, more preferably at least <NUM> wt%, most preferably at least <NUM> wt%. Said amount is preferably at most <NUM> wt%, more preferably at most <NUM> wt%, most preferably at most <NUM> wt%.

Preferably, the emulsifier composition is used in a liquid form, i.e. said emulsifier composition contains the AI component dispersed in a liquid phase which is soluble in acetone. The liquid phase of the emulsifier composition may contain triglycerides as the main component but may also contain monoglycerides, diglycerides, glycerol, glycolipids and fatty acids.

The emulsifier composition used in accordance with the invention may be produced by a process such as the one disclosed for example in <CIT> and <CIT>.

The inventive emulsion contains a lipid phase. The lipid phase may be a mixture of a fat which is liquid (the oil part in the fat phase) and a fat which is solid (usually referred to as hardstock fat) at ambient temperature (about <NUM>). Hardstock fat according to the present invention is defined as a fat that has a solid content at <NUM> (N30) of more than <NUM> wt%, preferably more than <NUM> wt%, most preferably more than <NUM> wt% at said ambient temperature. To determine the solid content of hardstock, the method presented in <CIT> (paragraphs [<NUM>]-[<NUM>]) may be used.

Preferably, the lipid phase contains a fat which is liquid at ambient temperature and is free of hardstock fat. By free of hardstock fat is herein understood that the content of said fat in the lipid phase is below <NUM> wt% relative to the mass of sad lipid phase, more preferably below <NUM> wt%, most preferably below <NUM> wt%.

The lipid phase of the inventive emulsion may thus contain a liquid fat (or liquid oil); a solid fat or a mixture of said liquid fat and said solid fat. The terms 'liquid oil' and 'liquid fat' may be used interchangeably within the context of the present invention. The term 'liquid oil' encompasses both triglyceride oils and diglyceride oils. Examples of the liquid oils that may be used in the present invention include without limitation various modified or unmodified vegetable and animal oils, such as palm oil, avocado oil, mustard oil, flaxseed oil, grape oil, peanut oil, coconut oil, olive oil, thistle oil, grape kernel oil, sesame oil, soybean oil, sunflower oil, linseed oil, cotton oil, rapeseed oil, low erucic rapeseed oil (Canola), corn oil, rice oil, safflower oil, kapok oil, sesame oil, evening primrose oil, fish oil and train (whale) oil and mixtures thereof.

Examples of solid fats include without limitation various modified or unmodified vegetable and animal solid fats, such as butter fat and chocolate fat, e.g. cacao butter, shea butter, sal butter; chicken fat; beef tallow; milk fat; lard and mixtures thereof. The above fats and oils may be modified by subjecting them to various treatments, examples thereof including without limitation hydrogenation, fractionation and/or trans-esterification.

The amount of the lipid phase in the inventive emulsion can vary within broad ranges and depends on the application in which the emulsion is intended to be used. For practical reasons, the amount of the lipid phase is preferably at most <NUM> wt%, more preferably at most <NUM> wt%, most preferably at most <NUM> wt% relative to the total weight of the emulsion. Preferably, the amount of the lipid phase is between <NUM> wt% and <NUM> wt%, more preferably between <NUM> wt% and <NUM> wt%, most preferably between <NUM> wt% and <NUM> wt%.

The lipid phase present in the inventive emulsion is in a form of droplets, distributed inside the aqueous phase (W<NUM>), for clarity also referred to as the external water phase. The droplets of the lipid phase (the "lipid droplets") preferably contain a plurality of water droplets (W<NUM>) and may have any shape and size.

Preferably, the lipid droplets have a size distribution characterized by a mean diameter D<NUM>,<NUM> of preferably at most <NUM>, more preferably at most <NUM>, most preferably at most <NUM>. Preferably, said D<NUM>,<NUM> of fat droplets is from <NUM> to <NUM>, more preferably from <NUM> to <NUM>, most preferably from <NUM> to <NUM>. More preferably, said D<NUM>,<NUM> of fat droplets is from <NUM> to <NUM>, more preferably from <NUM> to <NUM>, most preferably from <NUM> to <NUM>.

The water droplets (W<NUM>) have an average combined volume of at least <NUM>% of the volume of the lipid droplet containing said water droplets, preferably at least <NUM>%, more preferably at least <NUM>%. Said average combined volume is preferably at most <NUM>%, more preferably at most <NUM>%, most preferably at most <NUM>%. By combined volume is herein understood the sum of the individual volumes of the water droplets present in said lipid droplet. By average combined volume is herein understood the average of the combined volumes of water droplets calculated over a number of lipid droplets, preferably at least <NUM> lipid droplets, more preferably at least <NUM> lipid droplets, most preferably <NUM> lipid droplets. It was observed that the average combined volume of water droplets inside the lipid phase of the inventive emulsion may influence its organoleptic properties as well as its functionality.

To aid in homogeneously distributing the water droplets in the lipid phase, said water droplets preferably have a size distribution characterized by a mean diameter D<NUM>,<NUM> of preferably at most <NUM>, more preferably at most <NUM>, most preferably at most <NUM>. Preferably, said D<NUM>,<NUM> is from <NUM> to <NUM>, more preferably from <NUM> to <NUM>, most preferably from <NUM> to <NUM>.

Preferably, the total water content (W<NUM>) inside the lipid phase is between <NUM> wt% and <NUM> wt% relative to the total weight of the lipid phase, more preferably between <NUM> wt% and <NUM> wt%, most preferably between <NUM> wt% and <NUM> wt%.

The inventive emulsion also contains an external aqueous phase (W<NUM>) which is continuous, i.e. the lipid phase of the inventive emulsion is dispersed as droplets within the continuous water phase. A second emulsifier can be used to further stabilize the lipid phase inside the continuous aqueous phase (W<NUM>). Said second emulsifier is a high HLB emulsifier, i.e. with an HLB number of above <NUM>. Said second emulsifier is carboxymethyl cellulose (CMC).

Preferably, said second emulsifier is used in an amount of at least <NUM> wt% relative to the total weight of the inventive emulsion, more preferably at least <NUM> wt%, most preferably at least <NUM> wt%. Said amount is preferably at most <NUM> wt%, more preferably at most <NUM> wt%, most preferably at most <NUM> wt%.

The amount of the external aqueous phase in the inventive emulsion can vary within broad ranges and depends on the application in which the emulsion is intended to be used, e.g. of at most <NUM> wt%, more preferably at most <NUM> wt%, most preferably at most <NUM> wt%. Preferably, said amount is between <NUM> wt% and <NUM> wt%, more preferably between <NUM> wt% and <NUM> wt%, most preferably between <NUM> wt% and <NUM> wt%.

Preferably, the inventive emulsion is substantially free of acylglycerol-based emulsifiers, which herein are understood as molecules containing esters formed from glycerol and fatty acids. Particular examples of acylglycerols include without limitation polyglycerol polyricinoleate (PGPR), monoglycerides and diglycerides.

In a first preferred embodiment, the inventive emulsion is substantially free of PGPR. By substantially free is herein understood that the inventive emulsion contains less than <NUM> ppm PGPR based on its total weight, even more preferably less than <NUM> ppm. Most preferably the inventive emulsion is completely free of PGPR, i.e. the content of PGPR is zero ppm.

In a second preferred embodiment, the inventive emulsion is substantially free of mono- and/or diglycerides, i.e. mono- or di-esters of fatty acids and glycerol. Most preferably, the inventive emulsion is completely free of mono- and diglycerides. "Substantially free" and "completely free" bear herein the same meaning as that defined for PGPR.

In a third preferred embodiment, the inventive emulsion is substantially free, more preferably completely free, of PGPR, monoglycerides and diglycerides.

In a preferred embodiment, the inventive emulsion comprises:.

Preferably, the inventive emulsion further comprises one or more viscosity modifiers. Suitable viscosity modifiers include polysaccharides such as starches and gums, examples of said gums including without limitation gelatin, agar agar, pectin, alginic acid, sodium alginate, potassium alginate, beta- glucans, carrageenan, glucomannan, guar gum, gum ghatti, gum tragacanth, karaya gum, tara gum, fenugreek gum, xanthan, maltodextrins and/or locust bean gum. The term "gums", herein refers to all gum polysaccharides of various origins, e.g. from algae, bacteria or fungi.

The inventive emulsion may further contain solid structuring agent particles. Suitable solid particles may be platelets having a preferred average thickness of between <NUM> and <NUM> and agglomerates thereof. Preferably, said platelets are edible lipids. Such particles are known for example from <CIT>. In another embodiment, said solid particles are starch granules, wherein said starch granules or a portion thereof are situated at the interface between the two phases, i.e. the aqueous phase and the fat phase. The starch granules preferably have a small granular size in the range of approximately <NUM>-<NUM>, preferably <NUM>-<NUM>, more preferably <NUM>-<NUM>, most preferably <NUM>-<NUM>. Preferably, the amount of added starch granules in the inventive emulsion corresponds to approximately <NUM> - <NUM> vol% of the total emulsion. The amount of added starch granules is preferably determined by the coverage of a water droplet and coverage should be more than <NUM>%. A method of calculating an optimum amount of starch granules in the inventive emulsion as well as the size of said granules can be found in <CIT>.

The inventive emulsion is optimally stable against coalescence, i.e. the coalescence of water droplets with themselves and with the aqueous phase (W<NUM>) is reduced as well as the coalescence of the oil droplets with themselves. Also, Ostwald ripening effects in the inventive emulsions were largely prevented. Preferably, an osmotic agent is used to further minimize Ostwald ripening effects.

The inventive emulsion is desirably stable under storage at temperatures from <NUM> up to ambient temperatures. This storage stability may be determined for example by storing a sample of the product in a plastic container at <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM> for up to <NUM> weeks, more preferably up to <NUM> weeks, most preferably up to <NUM> weeks. An unstable emulsion may release in time oil (also known as oiling out) and/or water, effects known as phase separation. The extent of phase separation depends on the storage temperature and storage time. In case of the inventive emulsions, the presence of phase separation was determined after the storage time by visual examination (without the aid of a microscope) of the product's surface. Storage stable products do not show a phase separation (no oiling out/no water release) upon storage at <NUM> for at least <NUM> weeks, preferably at least <NUM> weeks.

The inventive emulsions have the advantage that they can be manufactured with practically any known process for making W/O/W emulsions. It was observed that the process for making the inventive emulsions may use standard equipment.

The inventive emulsion is preferably an edible emulsion. In case said edible emulsion contains a solid fat, ideally the solid fat content is chosen such that it melts or dissolves optimally at in-mouth conditions. An important indicator is the temperature at which the inventive emulsion breaks up. Preferably, the inventive emulsion breaks up at in-mouth conditions to provide a good oral response. Furthermore, the overall organoleptic impression is preferably smooth without any perceivable grains as this may result in what is generally known as a 'sandy', 'grainy' and/or 'lumpy' mouthfeel.

Also disclosed is a process for preparing the inventive emulsion, comprising the steps of:.

The temperature of the first aqueous phase (W<NUM>) and/or the lipid phase may be raised in order to facilitate mixing, e.g. typically between <NUM> and <NUM>, preferably between <NUM> and <NUM>. An osmotic agent may be added to said first aqueous water phase to help reducing Ostwald ripening effects in the enclosed water droplets, in particular during storage. Non-limiting examples of osmotic agents include glucose, salts and polyols, e.g. sucrose, fructose, sugars and artificial sweeteners.

The preliminary emulsion may be formed by mixing the first aqueous phase (W<NUM>) and the lipid phase with e.g. an Ultra Turrax mixer, preferably at a temperature between <NUM> and <NUM>, more preferably between <NUM> and <NUM>. Preferably, the preliminary emulsion contains water pockets in a continuous lipid phase, the water pockets preferably having dimensions between <NUM> and <NUM>, more preferably between <NUM> and <NUM>, most preferably between <NUM> and <NUM>.

The preliminary emulsion may be subjected to a homogenisation treatment in order to break the water pockets into a plurality of water droplets.

Homogenisation can be effected by a number of possible methods including, but not limited thereto, high shear treatment, pressure homogenisation, colloidal milling, intensive blending, extrusion, ultrasonic treatment and combinations thereof. Preferably, the homogenisation treatment is a pressure homogenisation treatment. Pressure homogenizers typically comprise a reciprocating plunger or piston-type pump together with a homogenising valve assembly affixed to the discharge end of the homogenizer. Suitable high pressure homogenizers include those manufactured by GEA Niro Soavi (IT).

During the high pressure homogenisation, the preliminary emulsion is subjected to high shear rates as the result of cavitation and turbulence effects. These effects are created by said emulsion entering the homogenizing valve assembly from the pump section of the homogenizer at a high pressure.

Preferably, the homogenisation is high pressure homogenisation carried out at a pressure of at least <NUM> bar, more preferably at least <NUM> bar, most preferably at least <NUM> bar. Preferably said pressure is at most <NUM> bar, more preferably at most <NUM> bar, most preferably at most <NUM> bar. Depending on the particular pressure and the flow rate of the emulsion through the homogenizer, one or more homogenisation passes can be used.

In one embodiment, the preliminary emulsion is homogenised by passing it a single time through the homogeniser. Preferably, the pressure used is between <NUM> bar and <NUM> bar, more preferably between <NUM> bar and <NUM> bar, most preferably between <NUM> bar and <NUM> bar.

In one embodiment, the preliminary emulsion is homogenised by multiple passes through the homogeniser, preferably at least <NUM> passes, more preferably at least <NUM> passes.

The preliminary emulsion is mixed with a second aqueous phase (W<NUM>) and the mix may be homogenized. For example the mixing may be carried out at low shear rates, e.g. by using an Ultra Turrax mixer at speeds between <NUM> and <NUM> rpm. The homogenisation may be carried out by high shear mixing, high pressure homogenisation, ultrasonic treatment and the like as enumerated hereinabove. The mixing and homogenisation can be combined in a single step and/or by using a single device or carried out sequentially. The mixing and homogenisation times can vary from a few second to a few minutes, suitable times depending on the homogenisation device being between <NUM> minute and <NUM> minutes.

The second aqueous phase (W<NUM>) preferably contains a second emulsifier, examples being given above.

Further disclosed is another process for preparing the inventive emulsion, comprising the steps of:.

Preferably, said D<NUM>,<NUM> of fat droplets is from <NUM> to <NUM>, more preferably from <NUM> to <NUM>, most preferably from <NUM> to <NUM>. More preferably, said D<NUM>,<NUM> of fat droplets is from <NUM> to <NUM>, more preferably from <NUM> to <NUM>, most preferably from <NUM> to <NUM>. The inventors observed that such a process is efficient and requires a reduced number of steps to achieve good results.

The invention further relates to a personal care product containing the inventive emulsion. "Personal care products" mean and comprise any cosmetic, hygienic, toiletry and topical care products including, without limitation, leave-on products (i.e., products that are left on keratinous substrates after application); rinse-off products (i.e., products that are washed or rinsed from keratinous substrates during or within a few minutes of application); shampoos; hair curling and hair straightening products; hair style maintaining and hair conditioning products; lotions and creams for nails, hands, feet, face, scalp and/or body; hair dye; face and body makeup; nail care products; astringents; deodorants; antiperspirants; antiacne; antiaging; depilatories; colognes and perfumes; skin protective creams and lotions (such as sunscreens); skin and body cleansers; skin conditioners; skin toners; skin firming compositions; skin tanning and lightening compositions; liquid soaps; bar soaps; bath products; shaving products; and oral hygiene products (such as toothpastes, oral suspensions, and mouth care products).

The invention relates further to pharmaceutical products comprising the inventive emulsion.

The invention relates further to feed products comprising the inventive emulsion.

The invention further relates to various food products containing the inventive emulsion, examples thereof including dips; sauces, e.g. dressing sauces; toppings; dairy-based products such as yoghurt, milk and cheese products; meat products; beverages; and soups. It was observed that the inventive emulsion had a high versatility allowing using it in a wide variety of applications.

In a preferred embodiment, the emulsifier composition is a composition comprising an Acetone-Insoluble (AI) component containing a Phosphatidyl Choline (PC), a Phosphatidyl Inositol (PI), a Phosphatidyl Ethanolamine (PE) and a Phosphatidic Acid (PA), wherein the amount of the PC is at most <NUM>% relative to the total weight of the composition and wherein the composition is characterized by a weight ratio R of at most <NUM>%, the ratio R being defined according to Formula <NUM> presented above. Preferably, R of the inventive composition is at most <NUM>%, more preferably at most <NUM>%, most preferably at most <NUM>%. Preferably, R is between <NUM>% and <NUM>%, more preferably between <NUM>% and <NUM>%, most preferably between <NUM>% and <NUM>%. Preferably the AI component is in a weight ratio of at least <NUM>% relative to the total weight of the inventive composition, more preferably at least <NUM>%, most preferably at least <NUM>%. Preferably, the AI is at most <NUM>%, more preferably at most <NUM>%. Preferably, the AI component is between <NUM> and <NUM> wt% of the total weight of the inventive composition. The emulsifier composition preferably has a ratio P<NUM>:P<NUM> of from <NUM>:<NUM> to <NUM>:<NUM>; wherein P<NUM> and P<NUM> are defined above in Formulas <NUM> and <NUM>, respectively. Preferably, the amount of PC in the inventive composition is at most <NUM>%, more preferably at most <NUM>%, even more preferably at most <NUM>%, most preferably at most <NUM>%, most preferably at most <NUM>%. Preferably the amount of PC is between <NUM>% and <NUM>%, more preferably between <NUM>% and <NUM>%, most preferably between <NUM>% and <NUM>%. The emulsifier composition of the invention preferably has a ratio P<NUM> as defined in Formula <NUM> of at most <NUM>. Said P<NUM> is preferably between <NUM> and <NUM>, more preferably between <NUM> and <NUM>. The preferred ranges for PA, PE and for the ratios P<NUM>, and P<NUM>, defined hereinabove are equally applicable and will not be repeated further herein.

In a preferred embodiment, the emulsifier composition is a composition comprising an Acetone-Insoluble (AI) component containing a Phosphatidyl Inositol (PI), a Phosphatidyl Ethanolamine (PE) and a Phosphatidic Acid (PA), wherein the composition is characterized by a weight ratio P<NUM> as defined in Formula <NUM> of between <NUM> and <NUM>. The preferred ranges for the AI, PA, PE, PI and PC contents and ratios R, P<NUM>, and P<NUM> as presented hereinabove are equally suitable for this composition and thus will not be repeated further herein.

The emulsifier compositions used in accordance with the invention may be produced by a process such as the one disclosed for example in <CIT> and <CIT> by choosing an optimal extraction process.

The invention further relates to food products, in particular those defined hereinabove, containing the compositions of the invention.

The invention is further presented with the help of the following examples and comparative experiments, without being however limited thereto.

An emulsifier composition (EC) obtained also from soybean oil and having a composition as presented in Table, as well as two other commercial lecithins one obtained from soybean (Leciprime) and one obtained from sunflower oil (Topcithin), which were not deoiled, were used. Other used emulsifiers were sodium caseinate (Na-Caseinate; <NUM> % moisture; <NUM> % protein on dry matter), whey protein isolate (WPI), carboxymethylcellulose (CMC; Degree of substitution=<NUM>-<NUM>; Viscosity <NUM>% solution=<NUM>-<NUM> mPa. s) and powdered soybean lecithin (Emulpur IP).

As the fat phase, high oleic sunflower oil (Hoso; Iodine Value= <NUM>; <NUM>% C18:<NUM>) and MCT-oil (Miglyol 812N) with approximately <NUM>% C8:<NUM> and <NUM>% C10:<NUM> were used.

The water phases W<NUM> and W<NUM> contained <NUM> Glucose (VWR Chemicals: BDH Prolabo, <NUM> Leuven, Belgium), <NUM> wt% of anti-microbial agent NaN3 (Sigma-Aldrich, Steinheim, Germany). Glucose was added as an osmotic agent to reduce Ostwald ripening effects. Glucose was used instead of a salt in order to avoid charge effects. To test the sensitivity of double emulsions towards dilution in different kinds of aqueous solutions, an emulsion containing <NUM>/L of the fluorescent marker <NUM>,<NUM>,<NUM>,<NUM>-Pyrenetetrasulfonic acid tetrasodium salt hydrate (PTSA; Sigma-Aldrich, Steinheim, Germany) in the enclosed water phase was prepared.

<NUM> wt% of EC or Leciprime or Topcitin was added to the oil phase after which this phase was heated to <NUM>. An Ultra-Turrax (type S25-<NUM>, IKA®-Werke, Germany) was used to prepare the preliminary W/O-emulsions (<NUM>/<NUM>, w/w) at <NUM>. The water phase was added gradually during stirring after which stirring was continued to obtain the final preliminary emulsion. Afterwards, the preliminary emulsion was processed using <NUM> pass through a Microfluidizer (type M110S, Microfluidics) operating at <NUM> bar while the temperature was maintained at <NUM> using a heating bath.

In case MCT-oil was used, the external water phase was mixed at room temperature with freshly prepared preliminary emulsion in a <NUM>/<NUM> (w/w) ratio with an Ultra-Turrax S25-<NUM> (IKA®-Werke, Germany) at <NUM>, <NUM> or <NUM> rpm for <NUM> minutes.

For preliminary emulsions prepared using Hoso as the oil phase, the preparation of a premix was necessary. The premix was prepared by mixing for <NUM> minute at <NUM> rpm using an Ultra-Turrax S25KV-<NUM>-IL (IKA®-Werke, Germany) which is a rotor-stator homogenizer with a larger diameter. Afterwards, mixing could be continued with an Ultra-Turrax S25-<NUM> (IKA®-Werke, <NUM> Germany) as described previously.

The external water phase only differs from the enclosed water phase in the presence of <NUM> wt% of either WPI, Na-Caseinate, CMC or powder soybean lecithin. Only the double emulsion containing the CMC is according to the invention. All samples were stored at <NUM> after preparation.

<FIG> reveals that the EC had a large influence on the enclosed water volume fraction. Indeed, when EC was used, during the <NUM> days of storage at <NUM>, the enclosed water volume fraction decreased with <NUM>±<NUM> %/day while a decrease with <NUM>±<NUM> %/day and <NUM>±<NUM> %/day is calculated for the commercial lecithins, respectively. Therefore, using EC, the highest storage stability could be reached while using sunflower lecithin the storage stability was very low. Finally, using soybean lecithin, an intermediate stability was obtained. As seen on the inset microscopic image of the W/O/W-emulsion prepared using sunflower lecithin and stored for <NUM> days at <NUM>, these emulsions are almost completely devoid of enclosed water (<FIG>,).

Double emulsions were prepared using long chain unsaturated triglyceride oil (Hoso) as the oil phase. EC was used as the low-HLB emulsifier while the high HLB-emulsifier was varied.

W/O/W-emulsions could be prepared without adding an additional high-HLB emulsifier to the external water phase. <FIG> shows that when whey protein isolate is used, the biggest droplets are obtained. The increased viscosity due to the addition of CMC to the external water phase has a beneficial effect during preparation as it reduces the viscosity ratio between dispersed and continuous phase.

Considering the storage stability of the double emulsion droplet size (<FIG>) it can be mentioned that during <NUM> days of storage at <NUM>, the droplet size increased with <NUM> and <NUM>% for CMC and WPI, respectively. In contrast, when using commercial (soybean) lecithin, the droplet size decreased to <NUM>% of its initial value.

Following the enclosed water volume fraction (%) as a function of storage time at <NUM> (<FIG>) reveals that CMC helps the storage stability of the W/O/W-emulsions. Indeed, the enclosed water volume fraction decreases with <NUM>±<NUM> and <NUM>±<NUM> %/day when WPI and soybean lecithin are used, respectively. In contrast, a very slow loss of enclosed water volume during storage of <NUM>±<NUM> %/day is noted in case CMC is added to the external water phase.

Because the enclosed water volume fraction was very low when Na-Caseinate was used as high-HLB emulsifier, it was tested whether the W/O/W-emulsions, prepared using EC as low-HLB emulsifier and WPI as high-HLB emulsifier, were sensitive to Na-Caseinate when this compound was added after production of the W/O/W-emulsion. Therefore, the double emulsions were diluted in an isotonic aqueous phase containing Na-Caseinate. In order to be able to compare the results of the aforementioned dilution, the double emulsion was diluted in two other isotonic solutions namely the enclosed water phase itself and the external water phase (containing <NUM> wt% WPI).

The release of a marker (PTSA) due to osmotic gradients between enclosed and external water was used to test the dilution effect. This was tested by dilution of the double emulsion with a hyper-(<NUM> glucose) and a hypotonic (distilled water) aqueous phase. <FIG> shows that adding a solution of <NUM> wt% Na-Caseinate in isotonic medium led to the release of enclosed water. This effect was, however, absent if the double emulsion was diluted in the enclosed (isotonic) water phase or in an isotonic water phase containing WPI (external water phase).

Claim 1:
A water-in-oil-in-water (W1/O/W2) emulsion comprising a lipid phase (O) and a water phase (W2), the lipid phase being distributed inside the water phase, wherein the lipid phase contains a plurality of water droplets (W1), wherein the water content inside the lipid phase is between <NUM> wt% and <NUM> wt% relative to the total weight of the lipid phase, wherein the water droplets are stabilized inside the lipid phase by a first emulsifier composition, wherein the first emulsifier composition comprises an Acetone-insoluble (AI) component containing a Phosphatidyl Choline (PC), a Phosphatidyl Inositol (PI), a Phosphatidyl Ethanolamine (PE) and a Phosphatidic Acid (PA), wherein PC is in an amount of at most <NUM>% relative to the total weight of the emulsifier composition and wherein the emulsifier composition is characterized by a phospholipid weight ratio R of at most <NUM>%, the ratio R being defined according to Formula <NUM>: <MAT>
wherein PC+PI+PE+PA is the sum of the individual weights of the respective constituents of the AI component and AI is the total weight of the AI component, and
wherein the water droplets (W1) have an average combined volume of at least <NUM>% of the volume of the lipid droplet containing said water droplets wherein the lipid phase is stabilised inside the water phase by a second emulsifier composition, wherein the second emulsifier composition is carboxymethyl cellulose (CMC).