GB1577994A

GB1577994A - Spun proteins and process for the production of the said proteins

Info

Publication number: GB1577994A
Application number: GB5120/78A
Authority: GB
Original assignee: Rhone Poulenc Industries SA
Current assignee: Rhone Poulenc Industries SA
Priority date: 1977-02-10
Filing date: 1978-02-08
Publication date: 1980-10-29
Also published as: DK58878A; JPS53106831A; CA1108923A; SE7801599L; ES466831A1; NL7801518A; CH628502A5; DE2805507A1

Abstract

The textured proteins are provided in the form of filaments 50 to 300 microns in diameter having, distributed in their cross-section, 1 to 60-micron fat particles, optionally containing one or more fat-soluble adjuvants, the said fats having a saponification number of not more than 5%. Preferably, the process for producing the said protein, consisting in mixing fat, optionally supplemented with one or more fat-soluble adjuvants, and a protein gel and in extruding the mixture in a suitable coagulating medium, is characterised in that a mixture is prepared under conditions such that the contact time between the protein gel and the fat, up to the time of passing through the extruder, does not exceed 2 minutes. The invention makes it possible to introduce into human food vegetable and/or animal proteins by giving them most of the qualities of animal meat.

Description

(54) SPUN PROTEINS AND PROCESS FOR THE PRODUCTION OF THE SAID PROTEINS (71) We, RHONE-POULENC IN DUSTRIES, a French Body Corporate, of 22 Avenue Montaigne, 75 Paris 8eme, France, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to spun proteins containing fatty material, which is distributed in the form of fine particles and to which other adjuvants have optionally been added. to the process making it possible to produce the said proteins, and to the installation making it possible to carry out the said process.

Much work has been carried out on the textuering of certan vegetable or animal proteins, in order to give them the appropriate appearance and gustative-qualities to make it possible to introduce them into human foodstuffs. Extrusion and spinning are the most commonly used methods for converting crude proteins into more refined products which can replace meat.

Spinning is td be understood herein as meaning a process for the formation of threads by extrusion of a solution, a dispersion or a gel through a plate provided with a small orifices (a die) of suitable shape and dimensions. Threads, filaments and fibres are the products obtained according to the spinning process: for simplicity these will be referred to as "filaments"; "a bundle" as used herein denotes the association of the said filaments. Spinning offers the advantage of reproducing the fibrous nature of means and makes it possible to obtain products which have varied appearance and nutritive value. However, it requires the use of purified proteins such as the isolates which are obtained as powders generally comprising more than 90% of proteins. In fact, products having less than 70% of proteins cannot be spun directly.

In order to be spun, the proteins must be converted beforehand into a protein gel; in this specification, a dispersion of protein isolates in a suitable dispersion medium, such as an alkaline solution, will be called a protein gel or a collodion, it being possible in some cases for the said dispersion to a colloidal solution, depending on the type of proteins dispersed and the dispersing agent employed.

In order to produce products which resemble meat as far as possible (meat being a term which, within the scope of the invention, encompasses both the flesh of mammals and that of birds, fish, crustaceans and other animals which man consumes for food), it is essential to reproduce the fibrous texture of the natural meat, to impart a good flavour to the protein fibres by adding various adjuvants, and especially to introduce a certain amount of well-distributed fatty material into the said fibres.

Various methods of adding fatty material having been proposed. A process is known (see French Patent No. 1,048,464) which consists in dipping the previously coagulated protein filaments in a bath of fat. An outer coating is thus obtained on the fibres. The fatty material is not, in fact, distributed inside the fibres by this process but remains on the outside, giving rise to a certain heterogeneity. Furthermore, it is not possible to predetermine the amount of fatty material which is introduced, or to retain it during a subsequent processing of the fibres, such as, for example, cooking.

It has been recommended to introduce the fatty material directly into the protein gel and to spin the mixture (see e.g. U.S.

Patent No. 2,730,447). However, the degree of homogeneity of the mixture, depends on the physical state of the fatty material. Also, prolonged contact of the fatty material with alkaline agents causes partial saponification of the said fatty material, giving rise to a modification of the taste and a lower digestibility of the product obtained. In addition, as the mixture of protein gel and fatty material is prepared in advance and the spinning takes a certain period of time, the quality of the fibres obtain is not constant.

It is therefore desirable to have proteins containing fine, homogeneously dispersed particles of fatty material on the inside, the said fatty material not being modified before its incorporation and being capable of being retained during the subsequent processing and during the various uses of the said proteins.

New spun proteins containing fatty material have now been found according to the present invention. The present invention provides spun proteins the filaments of which contain substantially uniformly distributed therein, particles of fatty material which have a diameter from 1 to 60 microns, and in which the degree of saponification incorporated in equal to at most 5%.

Throughout this specification the term "fatty material" is to be understood as meaning any so-called edible fatty material employed by itself or in a mixture, such as oils and animal or vegetable fats, and any edible fatty material containing at least one liposoluble adjuvant such as flavourings and scents, artificial aromas, preservatives such as antioxidants, colorants, emulsifiers, vitamins or nutritional additives such as N acetyl-L-methionine.

The percentage ratio of the saponified ester groups to all the ester groups in the fatty material mixed with the proteins will be referred to as the percentage of saponified fatty material or the degree of saponification of the fatty material.

The weight percentages expressed relative to the proteins refer to the dry product obtained by heating to constant weight, for example in an oven at llO"C.

The spun proteins according to the present invention generally have a mean molecular weight of 50,000 to 100,000. They comprise filaments, the diameter of which can vary from, say, 10 to 300 microns, and contain particles of fatty material dispersed throughout the entire cross-section of the filaments. The structure of the filaments can be determined by photographing a transverse section of the filaments on a microscope. after the fatty material has been extracted with hexane. The particles of fatty materials are found to have a diameter of 1 to 60 microns and commonly from 5 to 25 microns. In addition, the fatty material contained in the said filaments is not modified and its degree of saponification does not exceed 5%. as can be determined, in known manner, by determining its ester groups.

This invention further provides a process for the preparation of the spun proteins as described above, which consists in mixing fatty material with a protein gel and spinning the mixture in a suitable coagulating medium, the mixing being carried out under conditions which are such that the degree of saponification of the fatty material is at most 5% and that the fatty material is distributed in the protein gel in the form of particles having a diameter of 1 to 60 microns.

Saponification of the fatty material can be prevented or reduced to a level of less than 5% by limiting the duration of the contact between the protein gel and the fatty material, until the mixture passes through the due, to a maximum of 2 minutes.

Contact times from 1 to 20 seconds are very particularly suitable because the fatty material incorporated is then substantially free of saponified groups.

Numerous advantages are gained by the process of the invention. Protein filaments can be obtained which contain fine particles of fatty material which have a diameter of a few microns and which are homogeneously and uniformly distributed throughout the entire cross-section of the filaments. The introduction of the fatty material inside the protein fibre makes it possible to retain the material during subsequent use. It is important to point out that, by preventing any significant saponification, the process of this invention enables the fatty material incorporated to keep its taste and its integrity.

Furthermore, any desired amount of fatty material can be introduced into the spun proteins, because all the fatty materials sent into the feed circuit ends up in the spun product. Therefore, not only the quality but also the quantity of the fatty material is retained.

A further advantage of the process of the invention lies in the fact that the adjuvants can be introduced beforehand into the fatty material, which then makes it possible to incorporate them into the protein fibres without any denaturation. Until now, the various adjuvants have been introduced into the spinning solution, and therefore mixed with the protein gel; this frequently led to their degradation on contact with the gel, which was most frequently alkaline, and a large part of the adjuvants was lost during coagulation, neutralisation and washing.

Another method which is frequently used consists in depositing the adjuvants onto the protein filaments by coating, but it leads to a surface distribution of the adjuvants (flavourings and colorants), which is not at all satisfactory as regards the overall properties of the products obtained. The simultaneous introduction of the so-called fatty material and adjuvants, according to the process of this invention, makes it possible to overcome the abovementioned disadvantages.

This invention therefore also provides a specific process for the production of spun protein, in which an aqueous suspension of vegetable and/or animal protein is prepared, an aqueous alkaline solution is added to the said suspension in order to produce a protein gel, the fatty material, kept in the liquid state, and the said protein gel are sent separately, at suitable relative flow rates, into the inlet circuit for the die, at a point before or inside a mixing device, the two constituents are intimately mixed by any mechanical means for a period of time not exceeding two minutes, until they are spun, the mixture thus prepared is spun, and the filaments are coagulated in a coagulating bath.

The continuous filaments thus formed can be drawn, neutralised and washed.

Preferably the proteins employed according to the present invention are isolates of vegetable proteins such as soya sunflower, horse bean, pea, groundnut, corn, rapeseed, alfalfa, oats, barley and wheat, or animal proteins such as lactoproteins (casein, caseinate and seroproteins), gelatine, blood proteins and fish meals. Preferred raw materials are isolates of soya, sunflower, horse bean and milk casein.

The concentration of proteins in the aqueous suspension can vary within wide limits, suitably from 5 to 40% by weight, preferably from 10 to 25% by weight.

Preferably the alkaline solution used for preparing the protein gel is an aqueous solution of sodium hydroxide and/or of potassium hydroxide having a concentration such that the weight ratio of base/protein is 2 to 25%.

The fatty material incorporated into the protein according to the invention can be any edible fatty material, employed by itself or in a mixture; most frequently, various oils are used, such as groundnut oil, olive oil, corn oil, sunflower oil, soya oil, nut oil, coconut oio, sesame seed oil, cottonseed oil, safflower oil or fish oils, and/or animal or vegetable fats such as butter, margarine, beef suet, lard and chicken fat.

The proportion of fatty material added to the protein gel can vary, depending on the type of flesh which it is desired to imitate, from, say, 0.5 to, say, 60%, and preferably from 5 to 30%, by weight relative to the proteins.

The fatty material can contain any adjuvant, provided the latter is liposoluble. By way of examples of such adjuvants, there may be mentioned: natural flavourings or scents which are generally protein hydrolysates, liposoluble, edible, artificial aromas, liposoluble antioxidants such as ascorbyl palmitate, thiodipropionic acid, dilauryl thiopropionate and distearyl thiopropionate, liposoluble vitamins such as vitamin A, provitamin A or (3-carotene, vitamin D and vitamins B1 and B12, agents for strengthening aroma or taste, emulsifiers and liposoluble colorants.

Flavourings and scents, that is to say agents which serve the purpose of imparting the desired organoleptic and olfactory qualities to the proteins, are most frequently employed.

The natural flavourings or scents used in particular are protein hydrolysates such as ham aroma, beef aroma, pork aroma, onion aroma, fish aroma and other products extracted from the various types of meats or vegetables, provided that they can be mixed homogeneously with the fatty materials.

The proportions of lipsoluble adjuvants which are usually employed in the fatty material are such that they satisfy two conditions. Firstly, the mixture of fatty material and liposoluble adjuvant must be homogeneous. Secondly, the weight ratio of liposoluble adjuvant/proteins is from 0% to 15%. The weight ratio of lipsoluble adjuvant/proteins is preferably 3 to 6%.

However, these proportions can obviously vary depending on the type of adjuvant introduced.

An organic liquid can be used as the coagulating agent, but the use of an aqueous solution of an acid such as hydrochloric acid, acetic acid, lactic acid, citric acid, sulphuric acid, nitric acid, phosphoric acid or other acids such as sulphurous acid (aqueous solution of sulphur dioxide), or an aqueous solution of a salt such as sodium chloride, calcium chloride or sodium acetate, or an aqueous solution of an acid and of a salt such as those mentioned above, is preferred.

The concentration of acid in the bath is suitably from 0.5% to 10% by weght, but is preferably from 2 to 5% by weight. The concentration of the salts can also vary considerably, for example from 0.5% to 20% by weight, but it is preferably from 5 to 10% by weight. A preferred coagulating bath is an aqueous solution containing about 5% by weight of acetic acid and about 5% by weight of sodium acetate.

The process of the invention is conveniently carried out in the following manner.

The protein gel can be obtained by charging the alkaline solution into the protein dispersion, the amounts being predetermined.

A preferred variant of the process according to the invention consists in preparing, in a tank, an aqueous suspension of isolates of vegetable and/or animal proteins, by stirring for a period of time which varies with the nature of the protein employed from, say, a few minutes to 2 or 3 hours. The suspension is then sent into a homogeniser, into which an alkaline solution is also introduced in such an amount and at such a concentration that the pH of the mixture obtained is from 9 to 13.5, and preferably from 10 to 12, and that the weight ratio of base/protein is from 2 to 25%. This alkalisation, which makes it possible to prepare the spinnable protein gel, is carried out at 2 to 25"C and preferably from 2 to 70C; the temperature in the homogeniser can advantageously be maintained using a double-walled system.

The duration of the operation varies, according to the equipment (which can advantageously be a double screw, a malaxator or a static mixer), from, say, 3 to 4 minutes up to 30 minutes. In a discontinuous variant of the process, the total time of keeping the protein gel does not generally exceed 60 minutes. However, it is advantageous to carry out the process continuously, which considerably reduces this time.

The gel must, however, mature to a certain extent in order to reach the viscosity desired for spinning. The relatively low temperature at which the protein gel is kept makes it possible to prevent degradation of the proteins and, consequently, to prevent the unpleasant tastes and the drop in nutritive value which would result. The protein gel can advantageously be filtered, in known manner, in order to remove the insoluble materials, the presence of which would cause problems during spinning.

A fatty material (or a mixture of fatty materials) which is liquid, or kept liquid by heating, is then introduced into the inlet circuit of the die, at a point just before the latter. The amount of fatty material incorporated can be controlled, for example by a regulating pump, the speed of rotation of which makes it possible to adjust the proportion of fat. The protein gel and the fatty material can be mixed, for example, by a set of gear pumps and filters. The mixing can be improved by using a static mixer. The contact time of the fatty material with the proten gel is thus limited to the period of time necessary to obtain a good dispersion of the fatty material. This time should not generally exceed 2 minutes, but it is most frequently from 1 to 20 seconds.

According to the present invention, the mixture of protein gel and fatty material is then extruded through one or more dies.

The dies employed are usually of the type employed for spinning artificial or synthetic textiles. They generally have from 2,000 to 15,000 holes of diameter 0.05 mm to 0.30 mm.

The filaments obtained are collected in a coagulating medium in which the die is immersed. The temperature at which the coagulation is carried out can vary within wide limits, e.g. from 5 to 80"C, but it is preferably chosen in the region of the ambient temperature, that is to say 20 to 25"C. The filaments are then desirably drawn, the degree of which is determine- by the difference between the speed of drawoff, that is to say the speed at which the threads leave the coagulating medium, and the speed of take-up, it being possible for the latter to be from, say, 10 to 400% greater than the speed of draw-off. The drawing causes the more or less extensive orientation of the protein chains and thus makes it possible to influence the toughness or tenderness of the final fibre.In this way, it is possible to imitate any desired type of flesh.

The bundle of filaments thus obtained can then be nautralised to pH values of from 4.5 to 6.5, and preferably about 5.5, this being the value which corresponds to the pH zone of natural products. The choice of the composition and concentration of the neutralizing bath is determined by the acidity of the coagulating bath. The neutralising bath used can be an aqueous solution of a base such as sodium hydroxide or potassium hydroxide, an aqueous solution of a salt such as sodium chloride, calcium chloride, sodium bicarbonate or potassium bicarbonate, or sodium carbonate or potassium carbonate, or an aqueous solution of a base and of a salt such as those mentioned above.

The concentration of the neutralising bath can vary within wide limits. e.g. from 1 to 10% by weight for basic compounds and from 1 to 20% by weight for neutral compounds.

The bundle is then washed with water in order to remove the residual inorganic salts and to complete the neutralisation if necessary. This washing can be carried out by passing the bundle through a bath, by running water over the bundle on rollers, or by any other suitable system. Depending on the acidity of the coagulating medium, a single washing may be sufficient, without the neutralisation phase being necessary.

The moist fibres obtained generally contain 60 to 20% of water.

The invention will now be illustrated, merely by way of example with reference to the Figure of the accompanying drawing, which illustrates a typical installation for carrying out the process according to the invention.

The apparatus comprises a vat (1) into which protein isolates (25), on the one hand, and water (26) on the other hand, are fed. The vat (1) is preferably provided with a means of stirring, which is of any type usually employed, such as a propeller stirrer or an anchor stirrer. This means of stirring ensures a good dispersion of the proteins in water, in order to obtain an aqueous suspension. The aqueous suspension of protein is preferably sent by means of a pump (3) through pipe (20) into a homogeniser (5).

The alkaline solution contained in storage tank (2) is injected, by means of pump (4), into the pipe (20), downstream from the pump (3) and upstream from the homogeniser (5). The pump (4) is preferably a regulating pump. As a variant, and in order to ensure better mixing of the aqueous suspension of protein and the alkaline solution, the alkaline solution can be fed upstream from the pump (3), that is to say at the intake of the latter.

A homogeniser of any known type can, of course, be used as the homogeniser (5); for example, a static mixer can be used but screw homogenisers are particularly suitable. The protein gel leaving the homogeniser (5) can be directed into a filtering device (6).

The protein gel is then filtered by passing it through a gauze in order to obtain a filtered protein gel. The protein gel can optionally be subjected to several successive filtrations by passing it through filtering gauzes of decreasing mesh sizes.

The fatty material contained in tank (8) is introduced through an inlet tube (29), for example by means of a pump (9) which can be a regulating pump, and is incorporated into the filtered protein gel collected at the outlet of the filter (6) by tube (28). Optionally, for certain fatty materials having a melting point which is greater than ambient temperature, tank (8) is advantageously provided with a means of heating which can be incorporated into the wall of the tank or can also consist of a heating element immersed in the tank.

The mixture of filtered protein gel and fatty materia is introduced by means of a feed pump (10) into a die (12), the die being immersed in a coagulating bath (13). The feed pump (10) is preferably a regulating pump such as a gear pump. The feed pump (10) can also supply several dies arranged in parallel. Depending on the respective outputs of the feed pump (10) on the one hand, and of the pumps (9), (4) and (3) on the other hand, it can be desirable to partially recycle the filtered protein gel, upstream from the homogeniser (5), by means of pipe (7).

The die (12) is optionally preceded by a mixer (11); a static mixer, for example, is particularly suitable. In the Figure, the mixer (11) is shown in the delivery line of the feed pump (10); it can also be situated actually at the intake of the latter.

At the outlet of the die (12), filaments (21) form a bundle and are taken up on a roller (22). The bundle passes onto a roller (23) and then onto a roller (27) and is thus led into a neutralizing bath (14). Between the die and the roller (27), the filaments are subjected to drawing which takes place principally in the air. This drawing is such that the length of the filaments increases by 10% to 400%. The bundle of filaments is then carried, by means of guide rollers such as (24), into one or more washing baths (15).

On leaving the coagulating bath, the bundle of filaments can optionally be carried directly into the washing baths or baths, if neutralization is not necessary.

The process of washing the filaments by dipping them in the bath or baths (15) can be replaced by a process of washing the filaments by running water over them, it being possible for the filaments to be supported by means of an endless belt.

The bundle of washed filaments can then be drained, for example by passing it between two rollers (16).

The sequence of operations described can advantageously be carried out as part of a continuous process.

The following Examples further illustrate the present invention. In the Examples, the percentages are given by weight unless otherwise stated.

Example 1 13.5 kg of soya isolate and 80 litres of drinking water at 20"C are charged into a 120 litre vat.

The soya isolate has the following characteristics: water content: 7% protein content: 95% of the dry material, that is to say 88.3% of the powder pH: 4.5 t 0.2 density: 0.55 The stirring speed is 80 revolutions/minute and the suspension process takes 15 minutes. The suspension is charged into a mixer with Z-shaped blades which is thermostatted at 5"C.

After the suspension has been charged, it is rendered alkaline with 3.2 litres of 36 Baumé strength sodium hydroxide solution (an aqueous solution containg 400 g/litre sodium hydroxide). The mixture is malaxated for 20 minutes and charged into the hopper which is also cooled to 5"C.

Beef suet, kept in the liquid state (at 60"C), is incorporated, at a point before the feed pump, by means of a gear pump, delivering 2.4 cm3/revolution, which is adjusted so as to produce an output of suet of 1.7 kg/hour. The contact between the protein gel and the suet lasts about 20 seconds.

The gel is pumped onto a filter which is filled with 250 mesh stainless steel gauze (mesh size: 62 microns), and is then taken up by a feed pump having an output of 20 cm3/revolution and a speed of 54 revolutions/minute (that is to say an output of 64.8 litres/hour), which supplies a die having 3,954 holes of 0.15 mm diameter.

The duration of the spinning is about 80 minutes.

The coagulation is carried out in a bath, the initial composition of which is as follows: 80 litres of water 4 kg of acetic acid 4 kg of sodium acetate The coagulating bath is renewed with a 10% strength aqueous solution of acetic acid, at a rate of 26 litres/hour. The solution of acetic acid and of sodium acetate which forms the bath is removed at the same flow rate, in order to prevent the coagulating medium from becoming gradually richer in sodium acetate.

The threads are then washed by running drinking water over them at a flow rate of about 400 litres/hour.

These fibres are then subjected to discontinuous washing in a 2.5% strength sodium bicarbonate solution, and then to washing with water.

The filaments obtained exhibit the following characteristics: composition for 100 g of moist filaments: 70 g of water 30 g of solids, of which 4.5 g are suet and 25.5 g soya isolate pH: 5.8 diameter of the filaments: 115 to 130 microns diameter of the suet particles: 5 to 15 microns.

Exnmple 2 23 Litres of drinking water and 4.5 kg of sunflower isolate having a protein purity of at least 90% are charged into a malaxator thermostatted at 5 C. After stirring for 30 minutes. the mixture is rendered alkaline with 525 cm3 of 36 Baume strength sodium hydroxide solution. that is to say a ratio of 46.6 g of pure sodium hydroxide per kg of isolate.

After homogenization for 20 minutes at 5"C, a protein gel having a pH of 12 is obtained;it is allowed to stand for 10 minutes before spinning. The concentration of dry product in this gel is 15% by weight. The gel is charged into the spinning hopper which is cooled to 5"C. Lard kept in the liquid state (at about 40"C) is incorporated, at a point before the feed pump. by a gear pump which is adjusted so as to give an output of 24.3 cm of lard/minute. The mixture of gel and lard is sent through the die by the feed pump at a fow rate of 1.080 cm3/minute. The die used has 3.954 holes of 0.15 mm diameter.

The duration of the spinning is 30 minutes. The contact time of the protein gel with the lard is about 10 seconds.

The coagulation of the filaments is carried out as in Example 1 in a bath containing 5% of acetic acid and 5% of sodium acetate.

The threads are washed and taken up as in Example 1.

The filaments obtained having the following characteristics: composition for 100 g of moist filaments: 70 g of water 30 g of solids, of which 4.5 g are lard and 25.5 g are sunflower isolate pH 5.7 diameter of the filaments: 115 to 130 microns diameter of the lard particles: 5 to 15 microns.

Example 3 15.650 Litres of water and 4.8 kg of acid casein are charged into a malaxator thermostatted at 50C. The mixtures is stirred for 2 hours in order to obtain a homogeneous suspension. It is rendered alkaline by adding 525 cm3 of 36 Baumé strength sodium hydroxide solution, that is to say a ratio of 43.8 g of pure sodium hydroxide per kg of casein. The mixture is stirred for a further 20 minutes and allowed to stand for 10 minutes. 15% by weight of lard relative to the casein is incorporated by following the procedure of Examples 1 and 2; the injection flow rate of the fatty material is adjusted to 37 cm3/minute. The mixture is spun through a die having 3,954 holes of 0.15 mm diameter, at a feed rate through the die of 1,080 cm3/minute. The spinning takes 30 minutes.The filaments are coagulated in an aqueous bath containing 5% by weight of acetic acid and 5% by weight of calcium chloride; the pH of the coagulating bath is 2.2. The threads are drawn off from the coagulating bath at a speed of 10 metres per minute and are then washed. The contact time of the protein gel with the fatty material is about 10 seconds.

The filaments obtained exhibit the following characteristics: composition for 100 g of moist filaments: 67 g of water 33 g of solids, of which 4.95 g are lard and 28.05 g are casein isolate pH: 5.0 diameter of the filaments: from 125 to 145 microns diameter of the lard particles: 5 to 15 microns.

Example 4 13.5 kg of soya isolate and 80 litres of drinking water at 20"C are charged into a 120 litre vat.

The soya isolate exhibits the following characteristics: water content: 7% protein content: 95% of the dry material, that is to say 88.3% of the powder pH: 4.5 1 0.2 density: 0.55 The stirring speed is 80 revolutions/minute and the suspension process takes 15 minutes. The suspension is charged into a mixer with Z-shaped blades which is thermostatted at 5"C.

After the suspension has been charged, it is rendered alkaline with 3.2 litres of 36C Baumé strength sodium hydroxide solution.

The mixture is malaxated for 20 minutes and charged into the hopper which is also cooled to 5"C.

A fatty material, namely liquid palm oil (kept at 60"C) in which a liposoluble onion aroma is dispersed at a concentration of 0.66% by weight, is incorporated.

The incorporation is carried out, at a point before the feed pump, by a gear pump delivering 1.2cm3/revolution which is adjusted to 28 revolutions/minute in order to give an output of 2 kg/hour. The contact between the protein gel and the fatty material containing the onion aroma lasts about 10 seconds.

The gel is pumped onto a filter which is filled with 250 mesh stainless steel gauze (mesh size 62 p), and is then taken up by a feed pump, having an output of 20 cm3/ revolution and a speed of 54 revolutions/ minute (that is to say an output of 64.8 litres/hour, namely about 9.3 kg of soya per hour), which supplies a die having 3,954 holes of 0.15 mm diameter.

The duration of the spinning is about 80 minutes.

The coagulation is carried out in a bath having the following composition: 80 litres of water 4 kg of acetic acid 4 kg of sodium acetate The coagulating bath is renewed with a 10% strength aqueous solution of acetic acid, at a rate of 26 litres/hour. The solution of acetic acid and sodium acetate is removed at the same flow rate, in order to prevent the medium from becoming gradually richer in sodium acetate.

The threads are then washed by running drinking water over them at about 150 litres/hour.

The filaments obtained exhibit the following characteristics: composition for 100 g of moist filaments: 70 g of water 30 g of solids, of which 5.28 g are flavoured palm oil and 24.72 g are soya isolate. The amount of aroma is about 35 mg, which represents 0.35 g of aroma per kg of moist fibre.

pH 5.8 diameter of the filaments: 115 to 130 p.

diameter of the particles of fatty material: 5 to 15 .

Example 5 The procedure of Example 4 is followed, with the same equipment and the same amount of soya isolate.

A liposoluble fish aroma is dissolved in the liquid palm oil (kept at 60"C) at a rate of 33% by weight relative to the palm oil. The flavoured palm oil is incorporated, at a point before the feed pump, by a gear pump having an output of 1.7 kg/hour. The contact time of the protein gel with the flavoured palm oil is about 10 seconds.

The spinning, coagulation and washing are carried out as in the preceding example.

The filaments obtained have the following composition: for 100 g of moist fibres: 70 g of water 30 g of solids, of which 25.5 g are soyta and 4.5 g are palm oil containing 33% of fish aroma, which represents 1.5 g of aroma per 100 g of moist fibre.

Example 6 The procedure of Example 5 is followed, with the following differences: Fatty material used: lard liposoluble aroma: ham aroma at 44.5% strength in the mixture of lard + aroma.

The filaments obtained have the following composition per 100 g of moist fibres: 70 g of water 30 g of solids, of which 25.5 g are soya and 4.5 g are flavoured lard, which corresponds to 2 g of ham aroma per 100 g of moist fibre.

The process according to the invention can advantageously be used for the preparation of protein products, the texture, taste, appearance and nutritive qualities of which are very close to those of meat, and the cost price of which is lower than that of meat.

In fact, the fibres obtained can be bound together using, for example, egg albumin, fish albumin, gelatine, soya proteins, starch, casein, pectins, or gums such as carboxy methylcellulose.

Other ingredients can be added to. provide the desired gustative and olfactory properties and the desired appearance, provided the ingredient are edible and permitted by the legislation relating to foodstuff products. If necessary, various permitted foodstuff colorants, artificial or natural aromas, salt, sugar, wheat, gluten, monosodium glutamate, skimmed or dehydrated milk solids, spices, pepper and vitamins for example, may be added.

The invention therefore makes it possible to introduce inexpensive vegetable or animal proteins into human foodstuffs, imparting to them most of the qualities of the various types of animal meats which are the highprotein foodstuff products.

WHAT WE CLAIM IS: 1. A spun protein, the filaments of which contain, particles of fatty material which have a particle size from 1 to 60

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Claims

**WARNING** start of CLMS field may overlap end of DESC **.

The stirring speed is 80 revolutions/minute and the suspension process takes 15 minutes. The suspension is charged into a mixer with Z-shaped blades which is thermostatted at 5"C.

After the suspension has been charged, it is rendered alkaline with 3.2 litres of 36C Baumé strength sodium hydroxide solution.

The mixture is malaxated for 20 minutes and charged into the hopper which is also cooled to 5"C.

A fatty material, namely liquid palm oil (kept at 60"C) in which a liposoluble onion aroma is dispersed at a concentration of 0.66% by weight, is incorporated.

The incorporation is carried out, at a point before the feed pump, by a gear pump delivering 1.2cm3/revolution which is adjusted to 28 revolutions/minute in order to give an output of 2 kg/hour. The contact between the protein gel and the fatty material containing the onion aroma lasts about 10 seconds.

The gel is pumped onto a filter which is filled with 250 mesh stainless steel gauze (mesh size 62 p), and is then taken up by a feed pump, having an output of 20 cm3/ revolution and a speed of 54 revolutions/ minute (that is to say an output of 64.8 litres/hour, namely about 9.3 kg of soya per hour), which supplies a die having 3,954 holes of 0.15 mm diameter.

The duration of the spinning is about 80 minutes.

The coagulation is carried out in a bath having the following composition:

80 litres of water

4 kg of acetic acid

4 kg of sodium acetate The coagulating bath is renewed with a 10% strength aqueous solution of acetic acid, at a rate of 26 litres/hour. The solution of acetic acid and sodium acetate is removed at the same flow rate, in order to prevent the medium from becoming gradually richer in sodium acetate.

The threads are then washed by running drinking water over them at about 150 litres/hour.

The filaments obtained exhibit the following characteristics: composition for 100 g of moist filaments:

70 g of water

30 g of solids, of which 5.28 g are flavoured palm oil and 24.72 g are soya isolate. The amount of aroma is about 35 mg, which represents 0.35 g of aroma per kg of moist fibre.

pH 5.8 diameter of the filaments: 115 to 130 p.

diameter of the particles of fatty material: 5 to 15 .

Example 5 The procedure of Example 4 is followed, with the same equipment and the same amount of soya isolate.

A liposoluble fish aroma is dissolved in the liquid palm oil (kept at 60"C) at a rate of 33% by weight relative to the palm oil. The flavoured palm oil is incorporated, at a point before the feed pump, by a gear pump having an output of 1.7 kg/hour. The contact time of the protein gel with the flavoured palm oil is about 10 seconds.

The spinning, coagulation and washing are carried out as in the preceding example.

The filaments obtained have the following composition: for 100 g of moist fibres:

70 g of water

30 g of solids, of which 25.5 g are soyta and 4.5 g are palm oil containing 33% of fish aroma, which represents 1.5 g of aroma per 100 g of moist fibre.

Example 6 The procedure of Example 5 is followed, with the following differences: Fatty material used: lard liposoluble aroma: ham aroma at 44.5% strength in the mixture of lard + aroma.

The filaments obtained have the following composition per 100 g of moist fibres:

70 g of water

30 g of solids, of which 25.5 g are soya and 4.5 g are flavoured lard, which corresponds to 2 g of ham aroma per 100 g of moist fibre.

The process according to the invention can advantageously be used for the preparation of protein products, the texture, taste, appearance and nutritive qualities of which are very close to those of meat, and the cost price of which is lower than that of meat.

In fact, the fibres obtained can be bound together using, for example, egg albumin, fish albumin, gelatine, soya proteins, starch, casein, pectins, or gums such as carboxy methylcellulose.

Other ingredients can be added to. provide the desired gustative and olfactory properties and the desired appearance, provided the ingredient are edible and permitted by the legislation relating to foodstuff products. If necessary, various permitted foodstuff colorants, artificial or natural aromas, salt, sugar, wheat, gluten, monosodium glutamate, skimmed or dehydrated milk solids, spices, pepper and vitamins for example, may be added.

The invention therefore makes it possible to introduce inexpensive vegetable or animal proteins into human foodstuffs, imparting to them most of the qualities of the various types of animal meats which are the highprotein foodstuff products.

WHAT WE CLAIM IS: 1. A spun protein, the filaments of which contain, particles of fatty material which have a particle size from 1 to 60

microns, the degree of saponification of said fatty material being at most equal to 5%.
2. A spun protein according to claim 1, in which the fatty material is an edible fatty material or mixture of edible fatty materials.
3. A spun protein according to claim 1 or 2, in which the fatty material is an edible fatty material, or mixture of edible fatty materials, containing at least one liposoluble adjuvant.
4. A spun protein according to claim 3, in which the liposoluble adjuvant is a flavouring or scent.
5. A spun protein according to any one of preceding claims, in which the fatty material has a particle size from 5 to 25 microns.
6. A spun protein according to claim 1 substantially as hereinbefore- described.
7. A spun protein according to claim 1 substantially as described in any one of Examples 1 to 6.
8. A process for the preparation of a spun protein as claimed in any one of claims 1 to 7, which comprises mixing fatty material and a protein gel, and spinning the resulting mixture in a suitable coagulating medium, the mixing being carried out under conditions such that the degree of saponification of the fatty material in the spun protein is at most equal to 5% and that the fatty material is distributed in the protein gel in the form of particles having a particle size of 1 to 60 microns.
9. A process according to claim 8, in which the mixing is such that the contact time of the protein gel with the fatty material prior to spinning does not exceed 2 minutes.
10. A process according to claim 9, in which the said contact time is from 1 to 20 seconds.
11. A process according to claim 9 or 10, which comprises adding to an aqueous suspension of vegetable and/or animal protein an alkaline aqueous solution in order to produce a protein gel; supplying, separately, the fatty material, kept in the liquid state, and the said protein gel at suitable relative flow rates, to a mixing device which is upstream of a spinning devie, mixing the two constituents intimately such that the constituents are not mixed for more than 2 minutes prior to spinning, spinning the mixture and coagulating the resulting filaments in a coagulating bath.
12. A process according to claim 11, in which the fatty material, kept in the liquid state, is mixed with at least one liposoluble adjuvant prior to mixing with the protein gel.
13. A process according to any one of claims 8 to 12, in which the protein starting material is an isolate of soya, sunflower, horse bean or of milk casein.
14. A process according to any one of claims 8 to 13, in which the alkaline aqueous solution is an aqueous solution of sodium hydroxide and/or of potassium hydroxide.
15. A process according to any one of claims 8 to 14, in which the concentration of protein in the protein gel is from 2 to 25% by weight.
16. A process according to any one of claims 8 to 15, in which the pH of the protein gel is from 9 to 13.5.
17. A process according to claim 16, in which the pH of the protein gel is from 10 to 12.
18. A process according to any one of claims 8 to 17, in which the protein gel is maintained at a temperature of 2" to 250C.
19. A process according to clam 18, in which the protein gel is maintained at a temperature of 2" to 70C.
20. A process according to any one of claims 8 to 19, in which the fatty material is not liquid and is kept in the liquid state by heating.
21. A process according to any one of claims 8 to 20, in which the amount of fatty material incorporated is from 0.5 to 60% by weight relative to the protein.
22. A process according to claim 21, in which the amount of fatty material incorporated is from 5 to 30% by weight relative to the protein.
23. A process according to any one of claims 8 to 22, in which the concentration of liposoluble adjuvant relative to protein is from 0 to 15% by weight.
24. A process according to claim 23, in which the said concentration is from 3 to 6% by weight.
25. A process according to any one of claims 8 to 24, in which the fatty material is stored in the liquid state in a separate tank and is supplied via a regulating pump, to the supply line of the spinning die, the protein gel being supplied independently to said supply line via a mixer or is introduced into the supply line containing the fatty material just upstream of the mixer.
26. A process according to any one of claims 8 to 25, in which after spinning and coagulation the filaments are drawn 10 to 400%.
27. A process according to claim 8 substantially as hereinbefore described.
28. A process according to claim 8 substantially as described in any one of Examples 1 to 6.
29. Installation suitable for spinning protein by a process as claimed in any one of claims 8 to 26, which comprises, from upstream to downstream: a vat capable of receiving, on the one hand, protein isolate, and on the other hand, water, and comprising a means of stirring, a tank for storing the alkaline solution, a line into which the aqueous suspension of proteins from the vat and the alkaline solution from the storage tank can be passed, a homogeniser for the production of the protein gel, an inlet for introducing the fatty material into the said protein gel via a pump, a pump for feeding the mixture of protein gel and fatty material, and at least one die positioned for immersion in a coagulating bath, the said die being supplied by the said feed pump.
30. Installation according to claim 29, in which a filtering device is placed downstream from the homogeniser.
31. Installation according to claim 29 or 30, in which a mixer is placed upstream from the die or dies.
32. Installation according to any one of claims 29 to 31, in which the pump for introducing fatty material, and the feed pump, are regulating pumps.
33. A process according to any one of claims 8 to 26 which is carried out using an installation as claimed in any one of claims 29 to 32.
34. A spun protein whenever prepared by a process as claimed in any one of claims 8 to 28 and 33.