WO2003030664A1 - Use of a composition based on xanthan gum and galactomannan or glucomannan as a soft foam stabiliser and the foams based on said composition - Google Patents

Abstract

The invention relates to the use of a composition of xanthan gum and galactomannan or glucomannan as a soft foam stabiliser in acid and neutral media. The invention also relates to soft foams comprising said composition as a stabiliser.

Description

USE OF A COMPOSITION BASED ON XANTHANE GUM AND GALACTO- OR GLUCOMANNAN AS A STABILIZER OF SOFT FOAMS, AND THE FOAMS BASED ON THIS COMPOSITION

The subject of the invention is the use of a composition based on xanthan gum, as a stabilizer for soft foams as well as the soft foams stabilized by these compositions.

Manufacturers are constantly offering new products to meet consumer requirements. For several years now, manufacturers have been trying to modify the texture of their products, and in particular they have developed foam textures.

Many food products are offered in the form of foam. Mention may be made of yoghurt mousse, iced mousse. The same goes for the cosmetic field, where detergent foams are offered. They are also known as profusion products. In fact, foams are complex two-phase systems comprising at least two immiscible phases, at least one of which can be a liquid and the other is a gas. Gas bubbles, generally nitrogen, are dispersed in at least one liquid or solid phase.

Many techniques are used today for the manufacture of foams. These techniques are adapted to the different formulations and to the applications concerned. The conventional processes for producing foams (so-called expansion techniques) combine at least threshing and buliage, for example in Mondomix-type expanders, or in exchangers with a scraped surface. In fact, the threshing, also called shearing, is subjected to the liquid phase, also called the continuous phase, which following the buliage (injection of gas into the expansion chamber) allows the formation of a foam. Mention may also be made, as expansion techniques, of expansion by nucleation (case of certain drinks), or by expansion (case of aerosols in particular).

It is necessary for the production of the foam, that the liquid phase comprises at least one emulsifying agent. In order for the foam obtained to be stable over time, the foam must still be stabilized, so that it retains its foam texture, by at least one stabilizing agent incorporated in the starting system, or also by using an abundant agent, or an abundant base, having both emulsifying and stabilizing properties. Currently, the market for abundant products, especially in the food sector, is today mainly dominated by the use of gelatin, which acts both as an abundant agent and as a stabilizer. Recent problems linked to the discovery of bovine spongiform encephalopathy (BSE) have had repercussions negative on the use of gelatin in the food industry. In addition, the consumption of gelatin, banned by a certain number of religions, significantly reduces the sales prospects of these products. Many manufacturers are therefore looking for gelatin replacement systems. The characterization of the type of foam obtained can be done in different ways and many criteria have already been used to try to establish a classification of the foams. Among these criteria, one can indicate structural parameters (spherical foams / polyhedral foams, or closed cell foams / open cell foams). We can still classify these products according to their lifespan (a few seconds to a few minutes for transient foams, and a few hours or even a few months for permanent foams). One of the criteria also used to differentiate these products is their texture, in particular the rheological properties of the foam and more precisely of the continuous phase which constitutes the skeleton of the foam. From this criterion, we can differentiate between liquid foams, such as beer foam, for example, where the continuous phase is a liquid, and soft foams, such as, for example, chocolate foam, where the continuous phase is a viscoelastic gel. .

If obtaining these foams no longer poses particular problems, on the other hand their stabilization is a critical point in the success of these products. This problem arises particularly during the production of foams because their continuous phases undergo a significant shear, which can alter the properties of current stabilizers.

The object of the invention is to propose a new type of stabilizer. The present invention therefore proposes to use as a stabilizer for soft foams a composition based on xanthan gum and at least one galactomannan or a glucomannan, and containing no heteroxylans.

The invention also provides soft foams comprising such a composition as a stabilizer.

Soft foam is understood to mean foams whose continuous phase is a gel having viscoelastic properties. By way of example, the viscoelastic module is of the order of 10 ⁺² Pascal.

The use of the stabilizer according to the invention has the advantage that the soft foam retains its properties better, in particular its homogeneous foam structure, despite the aging phenomena which occur naturally, in particular Ostwald ripening or coalescence, and all especially drainage.

Indeed, among these aging mechanisms, drainage is a critical point in the case of aging of soft mosses. Drainage is directly related to the large density difference between the continuous phase and the dispersed phase, and results by the rise of the gaseous fraction over time in the foam, following a flow of the liquid between the bubbles, by gravity. In the case of so-called soft foams, the drainage phenomenon is to be avoided completely: this condition is imperative in the formulation of these systems for marketing reasons related to the presentation of the product. In so-called liquid foams, for which the continuous phase is of low viscosity, drainage is the most important destabilization process and above all it is inevitable.

Another advantage is that the stabilizer according to the invention can be used in the case of so-called “light” products low in fat or those with 0% fat.

From an organoleptic point of view, the use of the composition according to the invention has the advantage of retaining the melting character in the mouth and the smoothness of the abundant products in which it is incorporated.

Finally, surprisingly, this composition can replace gelatin. In addition, it has been found that this composition is more resistant to temperature than gelatin and makes it possible to improve the longevity of the foams produced, which is an advantage when the foams need to be transported or stored. The stabilization of the foam allows durable storage of the foam according to the invention. By durable storage means storage of at most 1 month. Throughout storage, the foam retains its soft foam properties.

Other advantages and characteristics of the present invention will become apparent on reading the description and the examples given purely by way of non-limiting illustration, which will follow.

The invention relates first of all to the use of a composition based on xanthan gum and at least one galactomannan or a glucomannan, and containing no heteroxylans, as a stabilizer for soft foams.

Xanthan gum is an anionic exocellular polysaccharide synthesized in particular by a bacterium Xanthomonas campestris. The basic motif of xanthan gum is composed of five osidic residues: the main chain consists of D-glucose units, linked together by β (1-4) bonds. It is a structure identical to that of cellulose. One out of two glucose is substituted at C3 by an anionic triosidic chain, comprising a glucuronic acid and two mannoses. The first mannose is partially acetylated and the terminal mannose can carry a pyruvic acid in the form of acetal with carbons 4 and 6. These levels of acetate and of pyruvate are variable according to the strains used and the conditions of the culture medium. For the usual xanthan, the degree of substitution in pyruvate is 0.3-0.5 while that in acetate is often close to 1. Galactomannans are nonionic polysaccharides extracted from the albumen of legume seeds of which they constitute the reserve carbohydrate. We can cite carob gum, it is extracted from carob seeds (for example Ceratonia siliqua), which is an evergreen tree native to Syria and Asia Minor, but cultivated all over the Mediterranean coast. Mention may also be made of guar gum which comes from guar seeds (for example Cyamopsis tetragonolobus). The galactomannans consist of a main chain of D-mannose units linked in β (1-4) on which are linked in α (1-6) D-galactose residues. The mannose / galactose ratio, characteristic of each galactomannan, is around 2 for guar gum and around 4 for locust bean gum.

As galactomannan used, mention may be made of those chosen from locust bean, tara, or guar gum.

The preferred galactomannan is locust bean gum.

Glucomannans have structures close to galactomannans, and include glucose in place of galactose, such as konjac mannan.

We prefer to use galactomannans to glucomannans.

It is advantageous to use galactomannans with a high molar mass, preferably above 1. 10 ⁶ g / mole. The respective proportions in the composition of galactomannans or glucomannans, and of xanthan gum are preferably between 99/1 and 1/99 by weight, and more particularly between 70/30 and 30/70 by weight and even more particularly between 60 / 40 and 40/60 by weight.

The concentration in the foam of the abovementioned stabilizing composition can vary according to the foams and according to their expansion rate.

This concentration in the foam is at least 0.05% by weight relative to the total weight of the foam.

In the case of 0% fat foams, the concentration may be a little higher than previously. Thus it can be at least 0.1%, preferably at least 0.3% by weight relative to the total weight of the foam.

It should be noted that the abovementioned stabilizing composition may also contain at least one emulsifying agent or at least one abundant base.

The term “emulsifying agent” is understood to mean any product capable of compatibilizing 2 phases, liquid / liquid or liquid / solid or else liquid / gas, in particular all substances which lower the interfacial tension between these 2 phases. The usual emulsifiers consist of a hydrophobic region (fatty acid or other lipid) and a hydrophilic and polar region (sugar, phosphate, ionized element). Among the emulsifiers used in the food sector, mention may in particular be made of proteins (for example egg yolk lecithins, milk proteins or proteins extracted from soya), phospholipids, fatty acids, partial glycerides (mono- and diglycerides), complex glycerides (tartaric acid, citric acid) or even sucroglycerides.

It should be noted that the soft foams stabilized by the use of the composition according to the invention have a higher melting temperature than those stabilized with the stabilizers of the prior art, in particular gelatin. This melting temperature can be adapted according to the intended application and by modulating the nature and the proportions of the constituents of the invention. It can also be adapted by varying the ionic strength. By way of example, this melting temperature is at least 40 ° C.

In addition, the foams stabilized by the use of the composition according to the invention have a continuous phase which is a gel having a viscoelastic module of at most a few hundred Pascal. Preferably the viscoelastic modulus of the foams according to the invention can be between 50 and 600 Pascal, more particularly it is between 100 and 200 Pascal.

The foams stabilized by the use of the composition according to the invention also have an expansion rate of at most 160% and which can be between 50 to 160%, preferably between 90% and 120%, more particularly it is 100%, percentages expressed by volume.

The expansion rate is calculated as follows: Expansion rate = Final volume - initial volume x 100

Initial volume This melting temperature can be at least 50 ° C. in the case of a composition based on xanthan gum and locust bean gum. In the case of a composition based on xanthan gum and guar gum, it can vary from 40 ° C. to 60 ° C.

The term melting temperature is understood to mean the temperature above which the foam melts.

The aforementioned stabilizing compositions can be used in cosmetic, food, detergent, agrochemical, pharmaceutical foams.

Mention may in particular be made, among food foams, of yoghurt foams, chocolate, Bavarian foams, cold meats, vegetable foams, fish foams. Among the cosmetic or detergency foams, mention may also be made, for example, of shaving foams, styling foams, abundant day creams. The invention then relates to soft foams characterized in that they comprise, as stabilizer, the above composition.

The foams are produced according to the conventional methods of manufacturing these. The soft foams can be foams having an acidic or neutral medium, in their continuous phase. They can also contain solid agents, such as fruit pulp, chocolate shavings, cereal petals, coconut powder or vanilla.

The soft foams according to the invention are preferably dairy foams, that is to say based on milk proteins.

More particularly, the foams according to the invention contain little or no protein from the eggs.

The foams which comprise, as stabilizer, the abovementioned composition, are more particularly yoghurt foams, chocolate foams, filling foams, such as for example Chantilly cream, cold meats, such as for example liver foams, vegetable mosses, fish mosses.

The following examples illustrate the invention without, however, limiting its scope.

EXAMPLES

Acid yogurt foam with 0% fat content: To obtain a creamy yogurt foam, using the composition according to the invention, the procedure is as follows:

1 / After heat treatment, a skimmed milk, which is enriched with 0.3% by weight of a xanthan / carob mixture (ratio 60/40), is dispersed with stirring at 60 ° C for 30 minutes. The mixture is then cooled to 43 ° C and sown at the rate of 4 AU (Acidifying Units) per 100 liters. Fermentation is carried out for 6 hours. The yogurt is then stored at 5 ° C overnight.

2 / The system obtained is then expanded using an expansion device by threshing with incorporation of air (Mondomix). The target expansion rate is 100% (which corresponds to 1 liter of gas injected for 1 liter of continuous phase). The foam is stored in an enclosure thermostatically controlled at 5 ° C.

The following table shows the classic formula of a yogurt foam without fat:

The foam obtained is comparable in texture and sensory qualities to the foam traditionally made with gelatin. The conservation of the product is of the order of 28 days. No drainage phenomenon is observed (the bubble concentration remains homogeneous over the entire height of the foam), nor sagging of the foam (loss of gas therefore loss of volume).

Frothy cream filling with fat

For the preparation of the swelling cream, a mixture of powders is made (sugar, milk powder, emulsifier, hydrocolloids). The water is heated to 65 ° C and the powders are then dispersed there with stirring. The vegetable fat is brought to 70 ° C. and incorporated into the mixture. The system is left at this temperature for 15-20 minutes, then the temperature rose to 90 ° C for a few seconds. Homogenization is carried out at 100 bars in one step, then a UHT treatment at 130 ° C. is maintained for a few seconds. The temperature of the mixture is lowered to 50-60 ° C, and the system stored at 5 ° C overnight. The expansion is carried out by beating and incorporating gas at 5 ° C using a Hansa® Mixer. The expansion rate obtained can vary from 100 to 200%.

The foam obtained is stable during storage for 28 days: it does not exhibit any drainage or sagging phenomenon. Chocolate mousse with fat:

The foam is prepared according to a process equivalent to that used previously for the frothy filling of cream. The recipe used is as follows:

Comparative example with gelatin:

The important advantage of the stabilizer according to the invention is its surprising resistance to shearing during the expansion operation, and this, unlike systems made from gelatin. Indeed, the stabilizer according to the invention retains its elasticity even after strong shear. The following table shows by way of example the values of viscoelastic moduli measured in dynamic regime by conventional rheological techniques immediately after shearing at 4000 revolutions per minute for 10 minutes from a base consisting of 0% yogurt (as defined in recipe 1), in the body of the profiteer.

The experimental results show that in the case of gelatin, the continuous phase becomes liquid, while in the case of the xanthan / carob mixture, the viscoelastic properties of the system are preserved. This characteristic allows instant immobilization of the bubbles in the foam at the outlet of the overrun and the certainty of being able to avoid the phenomena of drainage by gravity.

Claims

1 / Use of a composition based on xanthan gum and at least one galactomannan or one glucomannan, and not containing heteroxylans, as stabilizer of soft foams having an expansion rate of at most 160%. 2 / Use of a composition according to claim 1, characterized in that the galactomannan is chosen from locust bean, tara, or guar gum. 3 / Use of a composition according to one of claims 1 or 2, characterized in that the respective proportions in the composition of galactomannans or of glucomannans, and of xanthan gum are between 99/1 and 1/99 by weight, preferably between 70/30 and 30/70 by weight, and more particularly between 60/40 and 40/60 by weight. 4 / Use of a composition according to one of claims 1 to 3, characterized in that its concentration in the foam is at least 0.05% by weight relative to the total weight of the foam. 5 / Use of a composition according to one of claims 1 to 4, characterized in that the composition contains at least one emulsifying or abundant agent. 6 / Use of a composition according to one of claims 1 to 5, characterized in that the stabilized soft foams have a melting temperature of at least 40 ° C. 7 / Use of a composition according to one of claims 1 to 6 in cosmetic, food, detergent, agrochemical, pharmaceutical foams. 8 / Soft foam having an expansion rate of at most 160%, characterized in that it comprises, as stabilizer, the composition defined in claims 1 to 6. 9 / soft foam according to claim 8 characterized in that it is a yogurt mousse, a chocolate mousse, a cold meats mousse, a filling mousse, a mousse vegetables, fish mousse.