FR2793165A1 - Food-grade emulsions of water-oil or oil-water-oil type, have aqueous phase comprising hydrophilic thickener and oil phase comprising lipophilic surfactant and phytosterol - Google Patents

Abstract

The emulsions consist of an aqueous phase comprising hydrophilic thickener and continuous oil phase comprising lipophilic surfactant and phytosterol. The emulsions of water/oil or oil/water/oil kind consist aqueous phase comprising hydrophilic thickener and continuous oil phase comprising lipophilic surfactant and phytosterol. Lipophilic surfactant is preferably present in concentration up to 0.4 wt.%, phytosterol at concentration 0.05-10 (preferably 0.1-1) wt.%, and hydrophilic thickener at concentration 0.1-5 (preferably 0.8-2) wt.% (per total wt. of emulsion). Aqueous phase may comprise 3-12 wt.% of dissolved salt (NaCl, KCl) and/or sugar (glucose, maltodextrin, fructose) and preferably contains sodium chloride, in amount 2-10 wt.% per total wt. of emulsion, and has pH below 4 (preferably 3-3.5). Aqueous phase may also comprise hydrophilic surfactant, in amount 0.01-5 (preferably 0.5-3) wt.%. The emulsion preferably contains disperse phase, in amount 30-70 (preferably 50-65) wt.%, and has viscosity (at shear 1/sec) below 5 Pa s (preferably below 2 Pa s). An Independent claim is also included for French dressing consisting of water/oil emulsion or oil/water/oil emulsion as claimed.

Description

NEW WATER-IN-OIL EMULSIONS
OR OIL-IN-WATER-IN-OIL
The subject of the invention is new water-oil emulsions (inverse emulsion) and oil-in-water-in-oil emulsions (double reverse emulsions), in particular food emulsions.

Dressing sauces currently on the market are oil-in-water type emulsions. They have many disadvantages, among which we can mention:
-perception very marked acid (acetic acid is present in the water which constitutes the continuous phase) which leads to taste qualities far removed from traditionally prepared vinaigrettes; however, the pH value can not be adjusted because there would be problems of microbial stability;
the same marked acid character causes, by direct contact of the acidic aqueous phase on the plants, a rapid oxidation ("cooking" of the salad);
- Napping power too low because of the nature of the continuous phase of these emulsions: the plants are generally hydrophobic compounds on which a continuous aqueous phase does not ensure good wetting;
-texture too gelled that accentuates this weak nappying power.

 Thus, these products do not meet the expectations of the consumer because they are too far, in terms of taste and texture, "house" vinaigrettes, which are, remember, water-in-oil emulsions.

 A fluid and stable water-in-oil emulsion is thus sought, the dispersed aqueous phase of which consists at least in part of vinegar and whose continuous phase is oil.

 The emulsions of the water-in-oil type currently known in the agro-food field are of the margarine type, that is to say pasty products, and which are prepared under extremely precise operating conditions in order to control the crystallization of the product. oily or oily phase. Obviously, this type of emulsion and process can not answer the problem with the vinaigrette.

 Moreover, if one seeks to prepare a water-in-oil vinaigrette by simply mixing an aqueous phase with an oily phase, at various shears, a stable emulsion is not obtained. In the same way as "homemade" vinaigrettes, the emulsions thus prepared are not stable and are subject to phase shift.

 EP-A-0 664 677 in the name of Unilever discloses a water-in-oil vinaigrette which is supposed to be liquid and stable. However, the proportion of oil is very important, from 50 to 90% by weight (in the examples according to an oil / water ratio of 3/1) and thus the final dressing is too rich in oil. The stabilization obtained in this patent is due to the addition to the oily phase of a solid fat which acts as a structuring agent. The addition of this solid fat poses the same problem as the method referred to above for margarine, namely a precise control of the operating conditions: hot dissolution of the solid fat in the oil, controlled crystallization (shear and temperature precisely controlled). Thus, this document does not make it possible to obtain in a simple manner a salad dressing having a relatively high aqueous content (for example greater than 50%) and a fluid content.

 Thus, nothing in the prior art provides a fluid vinaigrette, stable, having organoleptic properties and texture similar to those of a "house" vinaigrette.

 The invention thus provides a water-in-oil or oil-in-water-in-oil-in-oil fluid and stable emulsion, the aqueous phase of which comprises a hydrophilic thickener and whose continuous oily phase comprises a lipophilic surfactant and a phytosterol .

 According to one embodiment, the lipophilic surfactant is a polyglycerol of ricinolic acid.

 According to another embodiment, the lipophilic surfactant is present at a concentration of less than or equal to 0.4% by weight, relative to the weight of the emulsion.

 In another embodiment, the phytosterol is p-sitosterol.

 According to another embodiment, the phytosterol is present at a concentration of 0.05 to 10% by weight, preferably between 0.1 and 1% by weight, relative to the weight of the emulsion.

 According to another embodiment, the hydrophilic thickener is cellulose gum or sodium carboxymethylcellulose (CMC).

 According to another embodiment, the hydrophilic thickener is present at a concentration of 0.1 to 5% by weight, preferably between 0.8 and 2%, relative to the total of the emulsion.

 According to another embodiment, the aqueous phase of the emulsion comprises a solute, preferably at a concentration of between 0.1 and 20% by weight, relative to the weight of the final emulsion, more preferably between 3 and 12. %.

 According to another embodiment, the aqueous phase of the emulsion comprises sodium chloride, preferably at a concentration of between 2 and 10% by weight, relative to the weight of the final emulsion.

 According to another embodiment, the pH of the aqueous phase is less than 4, preferably 3 to 3.5.

 According to another embodiment, the aqueous phase comprises a hydrophilic surfactant at a level of from 0.01 to 5% by weight, preferably from 0.5 to 3% by weight, relative to the total weight of the emulsion.

 According to another embodiment, the emulsion comprises, by weight, from 30 to 70% of dispersed phase, preferably from 50 to 65%.

According to another embodiment, the emulsion has a viscosity, measured under a shear of 1 s-1, of less than 5 Pa.s, preferably less than 2
Not.

 According to another embodiment, the emulsion is a water-in-oil emulsion.

 In yet another embodiment, the emulsion is an oil-in-water-in-oil emulsion.

 The invention also relates to a dressing consisting of a water-in-oil emulsion or an oil-in-water-in-oil emulsion according to the invention.

 The invention is now described in more detail in the description which follows.

The emulsion
The invention allows the manufacture of water-in-oil-in-oil-in-water-in-oil emulsions which are fluid and stable and which have reduced phenomena of coalescence or sedimentation.

The subject of the invention is such an emulsion comprising a lipophilic emulsifier, preferably
PRPG (polyglycerol polyricinoleate), and a phytosterol, preferably D-sitosterol in the continuous oily phase and a hydrophilic thickener in the aqueous phase.

 The term "fluid" is taken in its classical sense, and indicates that the emulsion is pourable.

The invention allows the preparation of vinaigrette type emulsions which are significantly more fluid than the oil-in-water vinaigrettes of the current market. By way of example, the viscosity, in Pa.s, measured at ls -1 for a commercial oil-in-water dressing, is about
Not. The dressing emulsions according to the invention can reach very low viscosities, less than 10
Pa.s, or even less than 5 Pa.s, preferably less than 2 Pa.s, the viscosities being measured at this shear of ls-1 (and at ambient temperature of 25 ° C.). Thus, unlike commercial oil vinaigrettes-water, vinaigrettes according to the invention can be poured very easily. Furthermore, in addition to their fluidity, the vinaigrettes according to the invention have improved napping power: the same nap effect can be obtained with up to 2 times less dressing, compared to a commercial oil-in-water vinaigrette.

 The emulsion is considered stable if no phase shift is observed visually, on the surface or at the bottom of the storage container during storage at 5 ° C or 23 ° C. Preferably, the emulsion is stable at least twelve month at 4 C and / or 1 month at 23 C. In fact, the emulsions according to the invention show no sign of coalescence and sedimentation (reversible phenomenon by simple manual stirring) is extremely reduced to 23 C and almost zero at 4 C (refrigerator temperature).

 In the food field, the invention naturally finds its application for the preparation of emulsified sauces, including salad dressings, salad dressings, etc. The vinaigrettes according to the invention are remarkably close, both organoleptically and from the point of view of texture, of "homemade" vinaigrettes. The invention therefore relates to food emulsions, and in particular salad dressings, dressing sauces, salad dressings, raw sauces, light salad dressings and others. The term "vinaigrette" is understood as a generic term encompassing all the forms mentioned above.

 The emulsion according to the invention generally comprises a dispersed aqueous phase representing from 30 to 70% by weight, relative to the total weight of the emulsion, preferably from 50 to 65%.

 When it is an oil-in-water-in-oil emulsion, the oily phase is distributed between the interior (internal oil) of the aqueous phase droplets and the outside (external continuous phase). The partition is carried out for example at a level of 20 to 60% by weight for the internal oil and from 10 to 50% by weight for the external oil, relative to the final weight of the double-inverse emulsion.

The final double-reverse emulsion comprises (as the single inverse emulsion), for example from 30 to 70%, preferably from 50 to 65%, by weight relative to the final weight of the emulsion, of the aqueous phase.

The aqueous phase
The dispersed aqueous phase comprises a hydrophilic thickener, which will be described in more detail below. The dispersed aqueous phase is of course composed of water with various additives. In the case of vinaigrettes, this aqueous phase comprises vinegar, optionally diluted in water and / or enriched with acid, for example citric or acetic acid. The vinegar is classic, for example cider, red wine, white wine, alcohol, raspberry, balsamic, etc.

 The aqueous phase may contain a solute, preferably at a concentration of 0.1 to 20%, more preferably between 3 and 12%, relative to the final weight of the emulsion. The solute is a salt (NaCl, KCl, etc.) and / or a sugar (glucose, maltodextrins, fructose).

The solute can improve the stability of the final emulsion, by the phenomenon of "Salting-out".

 In the case of the vinaigrette, the pH of the aqueous phase is preferably maintained at a sufficiently low level, for example less than 4, of the order of pH = 3 to 3.5, in particular to ensure microbial stability.

 The aqueous phase may also contain a hydrophilic surfactant of high HLB greater than 11. This surfactant, when present, is present in an amount of 0.01 to 5% by weight, preferably 0.5 to 3% by weight. % by weight, based on the total weight of the emulsion. This hydrophilic surfactant is advantageously present when the emulsion is an inverse double emulsion. This hydrophilic surfactant is useful for the preparation of the first oil-in-water emulsion, as will be described below.

This surfactant is advantageously a natural compound that can be used according to the principle of quantum satis (there is then no maximum legal content). By way of example, mention may be made of milk proteins, lecithins, etc. It is also possible to use synthetic surfactants (subject to regulation), for example Tween, propane-1, 2-diol alginate or starch. modified, sucro-esters and sucro-glycerides, etc.

 The aqueous phase may also contain buffering agents, antioxidants, stabilizers, flavoring agents, thickening or structuring agents, analytes and the like.

Those skilled in the art will be able to determine by routine tests the additives to be used, which will be in particular mustard (or aroma of), herbs, spices, etc.

The thickener
As a thickening agent for the aqueous phase, mention may be made of: xanthan gum, gum arabic, acacia gum, guar gum, cellulose gum or sodium carboxymethylcellulose (CMC), the pectins, the alginates, the ethers of cellulose (HPC, HEC, HMC, HPMC), carob flour, starch, maltodextrin, gelatin, microcrystalline cellulose, agarose, etc. The choice of the thickening or structuring agent, as well as its quantity, belongs to the general knowledge of those skilled in the art.

For example, a thicker of a low grade, ie having a viscosity at 1% by weight in water of less than 15 Pa.s, preferably less than 3, will be used.
Not. The thickener is used at a concentration of between 0.1 and 5% by weight, relative to the total of the emulsion, preferably between 0.8 and 2%.

 The preferred thickener in the invention is cellulose gum or sodium carboxymethylcellulose (CMC).

The oily phase continues
The continuous oily phase is conventional except that it comprises a lipophilic surfactant and a phytosterol, which will be described in more detail below.

 The oily phase consists of oil which is not soluble with water. As an oil, it is possible to use all the oils, whether vegetable or animal, as well as the fats in general. In the case of vinaigrettes, this oily phase consists mainly of edible oil, especially of plant origin, such as sunflower oil, peanut, olive, rapeseed, soya, etc. The situation is identical with double inverse emulsions, the phases being as conventional (apart from the features of the invention).

 The emulsions according to the invention may optionally also comprise a concrete fat. This is used as a compound to increase the viscosity (texture agent). They are interesting when stored in the refrigerator where the viscosity of the continuous phase increases considerably, which reduces the rate of sedimentation. These concrete fats, when they are used, are present in an amount of 0.05 to 2% by weight, preferably 0.05 to 1% by weight, relative to the weight of the final emulsion.

 The aqueous and / or oily phase may also contain conventional additives, such as liquid flavors, antioxidants, etc. The oily phase may in particular contain a lipophilic thickener, in an amount of between 0.1 and 1% by weight, relative to to the weight of the emulsion. This thickener can be in particular modified and hydrophobic silicon dioxide or hydrogenated concretes (commercially available under the name "oil absorber").

The surfactant
The lipophilic surfactant or emulsifier used in the invention is conventional, and is a surfactant of low HLB, less than 9. The choice of the emulsifier, as well as the amount thereof, depend on the use. final emulsion, storage characteristics, possible chemical reactions, etc.

Those skilled in the art will be able to proceed to the choice of the appropriate emulsifier by routine tests.

By way of example, mention may be made of: mono- or diglycerides of fatty acids, esters of mono- and diglycerides; polyglycerols, polyesters of polyglycerols; esters of thoxylated fatty alcohols; sorbitan esters; fatty esters; fatty alkanolamides; phospholipids; sodium stearoyl lactylate; the
Span; etc.

In the invention, polycondensed ricinoleic acid polyglycerol (or polyglycerol polyricinoleate), hereinafter PRPG, of formula: R 10 - (CH 2 -CH (OR 2) -CH 2 O) n -R 3 (I) is preferred
or
n is 2 to;
R1, R2 and R3 are each independently H or ricinoleic acid of formula (II), at least one representing this acid: H- [O-CH ((CH2) 5CH3) -CH2-CH = CH- ( CH2) 7-Colm-OH (ii)
or
m is 2 to 10.

 Preferably, n = 3-10 and m = 2-7; more preferably, n = 2-3 and m = 4-6.

 Examples of commercial PRPGs are Admul Wol 1403 (Quest), Radiamuls Poly 2253 (Fina) and Grindsted PGPR 90 (Danisco).

 The amount of emulsifier used depends on the end use. By way of example, certain emulsions of the invention may contain up to 20% by weight of emulsifier relative to the weight of the emulsion.

In general, the emulsifier represents, for example, up to 6% by weight, relative to the weight of the emulsion.

In some cases, the amount of emulsifier is limited by legislation in force; this is the case, for example, with vinaigrette, in which the quantity of emulsifier is regulated and remains low. By way of example, according to this regulation, the amount of PRPG emulsifier is at most 0.4% by weight, relative to the final weight of the emulsion.

 The emulsifier is in the oily phase, to which it is preferably added initially.

 According to an advantageous embodiment, the emulsifier used is a polyglycerol ester of ricinoleic acids, present at a concentration of less than 0.4% by weight, relative to the weight of the emulsion.

Phytosterol
The water-in-oil or oil-in-water-in-oil emulsion according to the invention also comprises a phytosterol (having a stabilizing effect). Phytosterols include cholesterol, campestrol, stigmasterol and P-sitosterol. Saturated homologs (stanols) are also contemplated. In the invention, preference will be given to the use of p-sitosterol, which, in addition to its function as a stabilizing agent, offers its more conventional function as a hypoglycemic and cholesterol-lowering agent. The α-sitosterol concentration can vary, for example, from 0.05 to 10% by weight, preferably from 0.1 to 1% by weight, relative to the final weight of the emulsion. Phytosterols, by their lipophilic character, are present in the continuous oily phase.

 This drastic stabilizing effect of phytosterols, especially β-sitosterol, combined with a lipophilic emulsifier on the water-in-oil and oil-in-water-in-oil emulsions is surprising, and constitutes an unexpected result.

The oily phase dispersed
The dispersed oily phase is generally similar to the continuous oily phase and comprises the same main ingredients. The dispersed oily (internal) phase may contain some additives, but it does not need to contain the low HLB lipophilic surfactant or phytosterol. Preferably, the internal oily phase comprises neither surfactant nor phytosterol.

The preparation process
The emulsions according to the invention may be prepared by any appropriate method. The person skilled in the art will be able to choose the most suitable process depending on the emulsion to be obtained, the starting components, the equipment, etc. Any apparatus that allows a mulsification is appropriate, that the emulsification is done in a laminar regime. When solid or pasty constituents are used, they are preferably heat-solubilized in all or part of the oil. The temperature necessary for the solubilization of these constituents will be determined case by case by those skilled in the art (typically 60 ° C.). The emulsification will preferably be carried out when the oily phase is at a temperature of approximately 25 to 30 ° C., and preferably before recrystallization of the solid or pasty constituents. Other operating conditions are however possible. Some examples of processes are given below.

 According to a first embodiment, a monodisperse water-in-oil emulsion is prepared in a laminar regime.

The process is a two-stage emulsification process, the first step comprising the manufacture of a premix and the second step the dilution of this premix.

The preparation step of the first can be considered as a thick phase mulsification step. This first is the result of the mixing (dispersion) of the aqueous phase of the final water-in-oil emulsion in a part of the oily phase composed of the various constituents of this phase and for example 5 to 25% of the oil. , relative to the final weight of emulsion. This first can be considered as an intermediate emulsion. The medium constituting the continuous phase of the first is generally viscoelastic. For the preparation of this premix, one can use several techniques, which the skilled person will appreciate. In general, the shear applied to obtain the first or intermediate emulsion is for example dispensed by a turbine generating a shear of 100 to 15000 s-1. The various constituents of the premix can be added continuously or not. It is also possible to place all the ingredients in a container and apply a shear such as to obtain the intermediate emulsion. For the preparation of the premix, any device ensuring emulsification is appropriate, such as a homogenizer (Ultra-Turrax type). For the preparation of the final emulsion, the premix is simply diluted in the remaining oil component of the oily phase. This dilution step is simply carried out by mixing the premix and the remainder of the constituent of the oily phase. This step is for example a low shear, for example dispensed by a turbine running at a speed below 200 rpm. By way of example, this step can be done in a mixer with blades rotating at a low speed.

 According to a second embodiment, a polydisperse water-in-oil emulsion is prepared in a turbulent regime.

This preparation route consists of directly homogenizing the aqueous and oily phases using any apparatus ensuring dispersion-homogenization. An example of this type of apparatus is Ultra-Turrax. Due to the nature of the applied shear (recombination turbulent defragmentation regime), the emulsion is polydisperse.

 According to a third embodiment, an oil-in-water-in-oil emulsion is prepared. This type of emulsion requires a two-step process. Firstly, a direct emulsion is prepared, then this oil-in-water emulsion is dispersed in an oily solution (oil, low HLB surfactant and phytosterol). The oil-in-water direct emulsion can be produced in a thick phase or in a turbulent regime depending on whether a monodisperse emulsion is desired or not.

Typically, the high HLB surfactant is dispersed in all or part of the aqueous phase supplemented with the hydrophilic thickening agent. The internal oily phase is then dispersed.

 The final emulsion is prepared by gradual incorporation under low shear (shear of 10 to 1000 s -1) of the direct emulsion into the remainder of the continuous phase comprising a low HLB lipophilic surfactant and phytosterol.

 The following examples illustrate the invention without limiting it, the invention being capable of numerous variants easily accessible to those skilled in the art and not to be limited to the particular embodiments which are described.

Characterization of stability
The stability of manufactured emulsions is studied according to two criteria: the coalescence failure rate and the sedimentation rate. On the emulsions produced are carried out the following tests:
measurement of the settling heights (h) relative to the total height (H) of a sample placed in a polypropylene test tube of 100 ml at 4.23 and 40 C.

 -Centrifugation at 4 and 23 C for an acceleration of 400 g for 15 minutes. Possible detection of coalescence at the bottom of the tube and measurement of the settling height in relation to the total height of the sample.

Example 1: Water-in-oil emulsion
The composition of the emulsion produced is as follows:

<tb><SEP> Ingredient
<tb><SEP> CMC <SEP> 1,2
<tb><SEP> Sugar <SEP> 3.0
<tb> Phase <SEP> aqueous <SEP> NaCl <SEP> 4.8
<tb> scattered
<tb><SEP> Water <SEP> 12.0
<tb><SEP> Vinegar <SEP> 39.0
<tb><SEP> Flavors <SEP> + <SEP> Colorants <SEP> 0,8
<tb><SEP> PRPG <SEP> 0.4
<tb> Phase <SEP> continuous <SEP> p-sitosterol <SEP> 0.7
<tb> lipid
<tb><SEP> Thickener <SEP> of <SEP> OIL <SEP> 0,2
<tb><SEP> (Oil <SEP> absorb)
<tb><SEP> Oil <SEP> 37.9
<Tb>
Salt, sugar and cellulose gum (CMC) are mixed dry in a tank. About 15% vinegar by weight is then incorporated, relative to the total weight of vinegar of the formula for homogenization.

Finally, the entire aqueous phase is added with stirring. The complete solubilization of the cellulose gum is reached after about 2 hours at room temperature. The aqueous phase is ready for emulsification.

 In a vat supporting the heating, the lipophilic thickener, phytosterol, PRPG and oil are placed. This mixture is brought to 60 C with stirring until complete solubilization of the solid compounds. It is allowed to cool to about 25-30 C. The oily phase is ready for emulsification which will be practiced before recrystallization of the solids (the open time is about 1 hour).

Finally, the aqueous and oily phases are combined in a tank where they will first of all be rough homogenized with a stirring paste, then more finely with the aid of a standard disperser-homogenizer.
Ultra-Turrax. The emulsification is done in 2 minutes.

 The emulsion thus prepared is very stable and shows little sedimentation at room temperature.

In the refrigerator, there is no evolution.

Example 2: oil-in-water-in-oil emulsion
The composition of the emulsion produced is as follows:

<tb><SEP> Ingredient <SEP>% <SEP>
<tb>SEP> oily phase <SEP> internal <SEP> Flavors <SEP> + <SEP> Dyes <SEP> 0,4
<tb><SEP> Oil <SEP> 19.6
<tb><SEP> CMC <SEP> 1.5
<tb><SEP> Sugar <SEP> 3.0
<tb> Phase <SEP> aqueous <SEP> NaCl <SEP> 4.8
<tb> scattered
<tb><SEP> Water <SEP> 12.0
<tb><SEP> Vinegar <SEP> 36.7
<tb><SEP> Proteins <SEP> of <SEP> 2.0
<tb><SEP> Lactoserum
<tb><SEP> Flavors <SEP> + <SEP> Colorants <SEP> 0,4
<tb><SEP> PRPG <SEP> 0.4
<tb> Oily phase <SEP> oily <SEP> external <SEP> p-sitosterol <SEP> 0.4
<tb><SEP> Thickener <SEP> of <SEP> 0.8
<tb><SEP> oil <SEP> (Oil <SEP> absorb)
<tb><SEP> Oil <SEP> 18.1
<Tb>
Salt, sugar and cellulose gum (CMC) are mixed dry in a tank. Then about 15 W of vinegar by weight, based on the total weight of vinegar of the formula for homogenization, is incorporated.

Finally, the entire aqueous phase is added with stirring. The complete solubilization of the cellulose gum is reached after about 2 hours at internal oily ambient temperature. The emulsification is carried out using an Ultra-Turrax type homogenizer. The direct emulsion thus produced is very stable, the diameter of the oil droplets is between 0.1 and 10 μm.

In a tank supporting the heating, the external oil phase (lipophilic thickener, phytosterol,
PRPG and external oil). This mixture is brought to 60 C with stirring until complete solubilization of the solid compounds. It is allowed to cool to about 25-30 C. The oily phase is ready for the mulsification which will be practiced before recrystallization of the solids (the open time is about 1 hour).

 The double emulsion is finally obtained by progressive incorporation under low agitation of the emulsion directly from the external oil phase. Typically, the double globules have a diameter of between 1 and 500 μm.

 The emulsion thus prepared is very stable and shows little sedimentation at room temperature.

In the refrigerator, there is no evolution.

Claims (16)

 1.-Water-in-oil or oil-in-water-in-oil emulsion fluid and stable, whose aqueous phase comprises a hydrophilic thickener and whose continuous oily phase comprises a lipophilic surfactant and a phytosterol.  The emulsion of claim 1, wherein the lipophilic surfactant is a ricinoleic acid polyglycerol.  3. Emulsion according to claim 1 or 2, wherein the lipophilic surfactant is present at a concentration of less than or equal to 0.4% by weight, relative to the weight of the emulsion.  4. Emulsion according to any one of claims 1 to 3, wherein the phytosterol is a-sitosterol.  5. Emulsion according to any one of claims 1 to 4, wherein the phytosterol is present at a concentration of 0.05 to 10% by weight, preferably between 0.1 and 1% by weight, relative to the weight emulsion.  6. Emulsion according to any one of claims 1 to 3, wherein the hydrophilic thickener is cellulose gum or sodium carboxymethylcellulose (CMC).  7. Emulsion according to any one of claims 1 to 6, wherein the hydrophilic thickener is present at a concentration of 0.1 to 5% by weight, preferably between 0.8 and 2%, relative to the total emulsion.  8. Emulsion according to any one of claims 1 to 7, wherein the aqueous phase of the emulsion comprises a solute, preferably at a concentration of between 0.1 and 20% by weight, relative to the weight of the emulsion. final emulsion, more preferably between 3 and 12%.  9. Emulsion according to any one of claims 1 to 8, wherein the aqueous phase of the emulsion comprises sodium chloride, preferably at a concentration of between 2 and 10% by weight, relative to the weight of the emulsion. final emulsion.  10. Emulsion according to any one of claims 1 to 9, wherein the pH of the aqueous phase is less than 4, preferably 3 to 3.5.  11. Emulsion according to any one of claims 1 to 10, wherein the aqueous phase comprises a hydrophilic surfactant at a level of 0.01 to 5% by weight, preferably 0.5 to 3% by weight, relative to the total weight of the emulsion.  12. Emulsion according to any one of claims 1 to 11, comprising, by weight, from 30 to 70% of dispersed phase, preferably from 50 to 65%.  13. Emulsion according to any one of claims 1 to 12, having a viscosity, measured under a shear of 1 s-1, less than 5 Pa. S, preferably less than 2 Pa. S.  14. Emulsion according to any one of claims 1 to 13, which is a water-in-oil emulsion.  15. Emulsion according to any one of claims 1 to 13, which is an oil-in-water-in-oil emulsion.  16.-Vinaigrette consisting of a water-oil emulsion according to claim 14 or an oil-in-water-in-oil emulsion according to claim 15.