FI66196B - FOERFARANDE FOER FRAMSTAELLNING AV TORRA MJOELKSYRABAKTERIEPREPARAT SOM AER ANVAENDBARA VID FRAMSTAELLNING AV LIVSMEDEL - Google Patents

Description

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(71) Vsesojuzny Nauchno-Issledovatelsky Institut Molochnoi Promyshlennosti,

Ljusinovskaya ulitsa 35, Moscow,

Vsesojuzny Nauchno-Issledovatelsky Institut Myasnoi Promyshlennosti, ulitsa Talalikhina 26, Moscow, USSR (SU) (72) Natalia Sergeevna Koroleva, Moscow, Lyudmila Alexandrovna Bannikova,

Moscow, Inna Vladimirovna Lagoda, Moscow, Nina Vasilievna Prusakova,

Moscow, Valentina Vladimirovna Krylova, Moscow, Nina Dmitrievna Likhonosova, Moscow, Margarita Mikhailovna Mikhailova, Moscow,

Vera Shakhromanovna Mirzoeva, Moscow, USSR (Sll) (74) Oy Kolster Ab (5 * 0 Method for the preparation of dry lactic acid bacterial preparations useful in the manufacture of foodstuffs - Förfarande för framstä11 Ning av torra mjölksyrabacteriepreparat, som är användbara vid framställ

The present invention relates to a process for the production of a dry bacterial preparation of lactic acid bacteria for use in the meat and dairy industry in the manufacture of processed dairy products, such as raw sour milk cheese and cream products, and in the manufacture of smoked sausages. More particularly, the invention relates to a process for preparing dry lactic acid bacterial preparations useful in food production by culturing lactic acid bacteria at optimum growth temperature in a milk-based broth supplemented with air donor at room temperature, buffering and mineral salts, cooling agents, with a preservative containing carbohydrates and buffer salts and by drying.

2 66196

A method is known in the art for preparing a dry bacterial fermentation product of lactic acid bacteria for the manufacture of processed milk by culturing lactic acid bacteria in a liquid medium containing whey, hydrolyzed milk, sodium citrate and trace elements, then removing the biomass from the medium by centrifugation and drying.

However, the yield of biomass in the known method is insufficient. Only 30-55% of the weight of active bacterial cells is retained after drying. In addition, the dry fermentation product dissolves slowly and incompletely.

A method is known in the art for producing a frozen lactic acid bacterial concentrate which can be used in cheese making by culturing lactic acid bacteria in a liquid medium containing whey, hydrolysed milk and sodium citrate, separating the biomass from the broth, mixing 10% of the biomass with the preservative, % by weight of sodium citrate and then the mixture obtained by freezing. The bacterial concentrate prepared by this method is stable for a maximum of 45 days at a temperature of -8 ...- 11 ° C.

Another method is known in the art for producing a frozen bacterial concentrate of lactic acid bacteria, which concentrate is used for the production of dairy products, such as raw sour milk cheese, and which has a significantly better shelf life than the concentrate prepared according to the above method.

The method is based on culturing lactic acid bacteria in a liquid medium containing whey, hydrolyzed milk, sodium citrate or acetate and growth promoters. The biomass is separated from the culture medium and mixed with the preservative in a ratio of 1: 1 and the resulting mixture is frozen as granules in liquid nitrogen. The preservative used contains 10-50% by weight of glycerin, 5-20% by weight of sucrose and 10% by weight of sodium citrate. The bacterial concentrate obtained by this method remains active for up to 6 months.

The main disadvantage of the latter two methods is that the finished bacterial concentrate must be stored at a low temperature, i. frozen at -10 ° C or less.

3,619,216 GB discloses a process for preparing a dry lactic acid bacterial preparation which retains its activity during long storage. In this method, lactic acid bacteria are cultured in a medium containing fresh milk, skim milk powder (or whey) and a dry matter content of 12 to 16% by weight; adding vitamin C and / or its salt, glutamic acid and / or aspartic acid and / or its salts; neutralizing the medium to a pH of 6.0 to 6.5, and drying, for example, by spraying or freeze-drying, in the latter case using a preservative such as inositol, sorbitol or mannitol.

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A dry preparation containing 22-107x10 bacterial cells per gram of preparation is obtained. The prepared preparation is not active enough to produce a product enzyme. The antibiotic properties of this known preparation are also not shown.

In addition, a method is known for producing a dry bacterial concentrate which can be used in the manufacture of processed milk and dry smoked sausages by culturing lactic acid bacteria in a liquid medium containing whey, hydrolysed milk, sodium citrate and trace elements, neutralizing with medium or aqueous NaOH , by separating the biomass from the culture broth, mixing it with a preservative containing 1-10% by weight of sugar, 1-5% by weight of gelatose, i.e. heat-treated gelatin which, when so treated, does not gel, 0.5-3% by weight sodium glutamate and 2.5-5% by weight of sodium citrate, followed by drying.

The main disadvantage of this and other above-mentioned methods in the preparation of bacterial fermentation products and concentrates from lactic acid bacteria is their poor activity, as a result of which the enzyme must first be prepared in the laboratory and then the enzyme used in production. This requires a lot of time, extra space and equipment.

The above-mentioned disadvantages can be eliminated by using the method according to the invention, which is characterized in that lactic acid bacteria are cultured in a broth containing: as a milk-based substance a mixture of fresh skimmed milk and skimmed milk powder with a dry matter content of 16-20% by weight; diluted 1: 5 and 4 66196 with water mixed with 1% skimmed milk; as a buffer salt 0.4 to 3.0% by weight of sodium citrate or acetate; as a nitrogen donor and as a source of mineral salts and vitamins 0.5-1.5% by weight of grain extract; and 0.0001 to 0.025% by weight of manganese sulphate as a trace element, the culturing of lactic acid bacteria is carried out, optionally neutralizing the medium; the cooled liquid bacterial preparation and the preservative are mixed in a ratio of 1: 0.1 to 1: 4, and the mixture is saturated with sterile air before drying, which is used to obtain a 20-50% by volume foamy suspension.

In order to increase the growth rate of lactic acid bacteria when cultured in the medium, it is preferable to use corn extract in an amount of 0.5 to 1.5% by weight of the medium as a nitrogen source and a source of mineral salts and vitamins.

For the preparation of a bacterial preparation from acidophilic bacteria having a high antibiotic effect, it is desirable to use a milk mixture containing skimmed milk and skimmed milk powder with a dry matter content of 16-20% by weight. The protein stabilizer - sodium citrate - is added to the raw milk material in an amount of 0.1-0.4% by weight and the acidophilic bacteria are cultured at a temperature of 40-45 ° C for 4-6 hours at a pH of 4.1-4, 8 to achieve.

Sodium acetate, cereal extract, manganese sulfate and vitamin B 2 are then added to the medium and the culture is continued at 40-45 ° C for a further 12-14 hours to reach a pH of 3.5-3.9; at the end of the culturing process, zymase is added to the liquid bacterial composition.

In order to maintain the viability of the lactic acid bacterial cells contained in the finished composition, it is desirable to dry the medium mixed with the preservative by sublimation for 10-24 hours at an initial temperature of -30 ° C to -42 ° C and a final temperature of 40-50 ° C and pre-cooling to -50 ° C. ..- 60 ° C for 1.5-4 hours, during which time the mixture is saturated with air before drying.

The present invention is carried out as follows. A broth is prepared for culturing lactic acid bacteria. The broth is made from a raw milk material, for example sterilized 5 66196 clarified whey diluted 1: 5 with water. Buffer salts, e.g. sodium citrate or sodium acetate, trace elements, nitrogen sources, mineral salts and vitamins, are then added, the last three constituents of the broth being, e.g. The corn steep liquor is a complex food source for microorganisms and its addition below said limit is not sufficient to form the desired number of cells and an amount greater than said limit gives an excessive increase in the acidity of the broth.

The trace element to be added may be, for example, manganese sulphate. The finished broth is sterilized, e.g., at 121 ° C for 10-15 minutes and cooled to the culture temperature of lactic acid bacteria, i.e. to 30-45 ° C and aqueous Na 2 CO 3 or NaOH is added to maintain the initial pH. The lactic acid bacterial inoculum is then added to the broth and cultured. The cessation of lactic acid bacteria culture is mainly determined by the pH, which should currently be in the range of 3.5 to 4.9.

The broth is cooled to 6-10 ° C, centrifuged and the resulting biomass is mixed with the preservative in a ratio of 1: 0.1-1: 4 and the resulting mixture is saturated with air to form a foamy suspension containing 20-50% by volume of air. This shortens the drying treatment time and improves cell viability.

Drying can be carried out by any known method, e.g. spray drying, with a drying chamber inlet temperature of 120-150 ° C and a drying chamber outlet temperature of 50-60 ° C.

The most preferred method of drying bacterial preparations, while maintaining the maximum possible number of live lactic acid bacteria and good solubility, is drying by sublimation.

In this case, the suspension is frozen at -50 to -60 ° C for 3-5 hours. The frozen preparation is dried in a sublimation apparatus under the following conditions: initial temperature -30 ° C to -42 ° C, final temperature 40 ° C to 50 ° C, drying time 8-10 hours.

The dried bacterial preparation of lactic acid bacteria is sealed in waterproof cases. The dry bacterial preparation of a lactic acid bacterial culture prepared by the present method can be used in the production of several processed milk products as well as in the production of semi-dry smoked sausages.

Depending on the intended use of the formed bacterial preparation, the stock cultures cultured in the broth consist of the following bacteria Streptococcus bulgaricum, Lactobacterium acidophilum, Streptococcus lactis, Streptococcus acetoinicus, Streptococcus diacetylactis, Streptococcus crem. These lactic acid bacteria are known and are described in Bergey's Manual of Determinative Bacteriology, with the exception of Lactobacterium acidophilum, which is used as a synonym for L. acidophilus.

Lactic acid bacterial strains Lactobacterium acidophilum Ep-1 and Ep-2 are also known and are described in detail in: L.A. Erzynkyan, “Biological Peculiar Features of Some Races of Lactic Acid Bacteria, published by the Armyanian SSR, Erevan, 1971, pp. 79-81.

If the dry bacterial preparation is intended for use in the manufacture of processed milk products, the method is applied as follows.

First, the broth is prepared using, for example, whey having a pH of 4.5 to 4.6 and grain extract (liquid or dry) as a nitrogen source as raw milk material. In addition to the grain extract, water is added in a ratio of 1: 5, sodium acetate or sodium citrate and manganese sulphate.

The whey is pre-sterilized by heating it to a temperature of, for example, 121 ° C and holding it at that temperature for 15 to 20 minutes, and then the whey is clarified by separation, diluted with water, adjusted to pH 6,2 to 6,8 and grain extract (1% by weight). ), sodium acetate (3% by weight) and magnesium sulphate (0.02% by weight). For the preparation of whey with a pH of 6.2 to 6.8 as described above, for example, 100 l of whey are used and 500 l of water, 600 g of dry grain extract or 6 l of liquid grain extract, 18 kg of sodium acetate or sodium citrate and 0 l of , 1 kg of manganese sulphate.

The prepared medium is sterilized by heating it to, for example, 121 ° C and keeping it at this temperature for 15-20 ml for 7 66196 minutes and then cooling it to an optimum temperature of, for example, 30-45 ° C for culturing lactic acid bacteria.

To the cooled medium is added 1% by weight of sterilized skim milk and then a culture of lactic acid bacteria in an amount of 1 to 5% by weight. As a lactic acid bacterial culture, for example, a two-component fermentation product consisting of Streptococcus lactis and Streptococcus acetoinicus species can be used. The cultivation process is allowed to continue for 8-10 hours. Two or three hours before the end of the culture process, the liquid culture product is neutralized to pH 6.0-6.5 by adding or aqueous NaOH.

At the end of the culture process, the lactic acid bacterial cells are removed from the culture medium, for example by centrifugation. Before centrifuging the culture solution, it is cooled to a temperature of 6-10 ° C. The treatment is performed under aseptic conditions.

The bacterial preparation obtained after centrifugation of the culture medium is mixed with the preservative, preferably in a ratio of 1: 4. The preservative contains 2.5% by weight of sugar, 1.5% by weight of sodium acetate or citrate, 1.5% by weight of gelatin, 0.25% by weight of sodium glutamate and 2.5% by weight of skimmed milk and the rest is water.

The bacterial preparation mixed with the preservative is then saturated with sterile air in an amount of 20 to 50% by volume to form a foamy suspension. The resulting suspension is frozen in a layer 7-10 mm thick at -50 ...- 60 ° C for 3-4 hours. The frozen suspension is dried in a sublimation apparatus with an initial temperature of -30 to -42 ° C and a final temperature of 40 to 50 ° C. Drying time is up to 10 hours. The dried bacterial preparation is ground into flour and packaged under aseptic conditions.

One dose of the preparation (1 g) contains 300-600 billion bacterial cells.

The moisture content of the preparation is 2.5-4.5% by weight. Said dose of bacterial preparation is sufficient to flow 300 liters of milk in 8-16 hours and to give a prepared fermentation product with an acidity in the range of 72-100 ° T.

With the help of said preparation, it is possible to prepare both the product enzyme and the dairy products themselves, e.g. raw sour milk, dumpling cheese, cream products, buttermilk, yoghurt.

; t 8 66196

To prepare the enzyme or product, one portion (1 g) of the bacterial preparation is dissolved in 0.5 liters of skim sterile milk and activated for 30-40 minutes at 30-40 ° C. The activated liquid bacterial preparation is then acidified with 300 liters of milk.

If the dry bacterial preparation is intended for use in the manufacture of semi-dry smoked sausages, the method is applied as follows.

The raw material for the preparation of the culture medium is skim milk to which dry milk has been added so that the dry matter content is preferably 18% by weight.

Sodium citrate is then added to the milk at 4 g per liter of milk. The mixture is sterilized and cooled to 40-45 ° C. A culture of the acidophilic bacterium Lactobacterium acidophilum is added to the culture medium prepared as described above in an amount of 2 to 5% by weight of the inoculum. The resulting mixture is stirred and cultured at 40-45 ° C for 4-5 hours to a pH of 4.1-4.8. The following additives are then added: 3% by weight of sodium acetate in the form of a sterile 40% aqueous solution, 1% by weight of cereal extract, 0.0001% by weight of manganese sulphate as 0.01% sterile aqueous solution and 0.0003% by weight of vitamin B 2.

The culture is then continued for 12-14 hours to a pH of 3.5-3.9. 0.01% by weight of zymase is added to the liquid bacterial preparation and the mixture is cooled to 8-10 ° C.

At the end of the treatment, 1 ml of liquid bacterial preparation contains 600-2500 million bacterial cells. This preparation is mixed with a preservative. To this end, 10% by weight of a preservative containing 20% by weight of a sugar solution and 4% by weight of an aqueous solution of sodium acetate are added to a chilled liquid bacterial preparation of acidophilic bacteria. The liquid bacterial concentrate containing lactic acid bacterial cells and their cultures and preservative is mixed thoroughly and the resulting suspension is saturated with sterile air in an amount of 20 to 50% by volume to form a foamy suspension.

The cell suspension formed under aseptic conditions is cooled to a layer of 5-10 thick thickness at -50 ° C over 1.5-2 hours.

9 66196 This frozen product is dried in a sublimation apparatus under the following conditions: temperature at the beginning of drying -30 ...- 42 ° C and at the end 40-50 ° C. Drying time is 20-24 hours.

The dried bacterial preparation of acidophilic bacteria is packaged under aseptic conditions.

A dry bacterial preparation of acidophilic bacteria is used in a regenerated form of 250 g / 100 kg of raw material. It is dissolved (regenerated) in boiled water cooled to 40-45 ° C in an amount of one part to three parts of water and kept at room temperature (18-22 ° C) for two hours.

The pH of the water-regenerated acidophilic bacterial preparation for semi-dry smoked sausages should be 4.1-4.9 and the acidity 320-360 ° T; microscopically, the preparation contains medium-sized bacteria individually or in chains.

Prior to addition to the filling, the regenerated bacterial preparation of acidophilic bacteria is cooled to a temperature of 2-8 ° C and, if necessary, kept at this temperature for a maximum of 48 hours. It is added to 1 1/100 kg of raw material when preparing the stuffing at the beginning of the beef or lean pork cutting process.

The bacterial preparation has more cells and a higher activity than the one prepared according to the known method. This makes it possible to prepare a product enzyme from it without having to prepare a laboratory enzyme or to add a bacterial preparation directly to the original raw material. The quality of the finished product improves, the workload and energy requirements decrease and the amount of equipment required is lower.

The bacterial product on display is durable and very simple to use.

The antibiotic effect of the preparation prepared according to one of the above embodiments and used for the preparation of semi-dry smoked sausages is high against undesired microorganisms.

Its acid-forming ability improves the tightness of the product and its taste properties. If technological requirements are taken into account during cooking, 1 g of smoked sausage can contain up to 10 million lactic acid bacterial cells, which doubles the sausage production process and increases the yield of the finished product by 8-10%.

10,661 96

In order to clarify the present invention, examples of its implementation are given below.

Example 1

The whey obtained from the preparation of sour milk cheese with a pH of 4.5 is sterilized at 121 ° C for 15 minutes.

It is then cooled to 60 ° C and separated to add proteins.

500 l of water, 18 kg of sodium citrate, 6 kg of liquid maize extract, 0.15 kg of manganese sulphate are then added to 100 liters of clarified whey and the pH of the medium is adjusted to 6.8 by adding saturated sodium bicarbonate solution.

The medium is sterilized at 0.1 MPa and 121 ° C for 20 minutes and cooled to 30 ° C.

To the obtained medium are added 6 l of sterile skim milk and 18 l of culture symbiosis containing one part by weight of Streptococcus lactis bacteria, species 90 and one part by weight of Streptococcus acetoinicus bacteria, species 704.

The culture is then performed at 30 ° C for 10 hours.

In culture, the pH of the broth is 6.4. At the end of the culture, the broth is cooled to 10 ° C and the bacterial cells are separated therefrom by means of a bacterial filter. The removed cells, 7,5 kg, are mixed with 22,5 l of a sterile solution of the preservative containing 5% by weight of dried skimmed milk, 2,5% by weight of sugar, 1,5% by weight of sodium citrate, 1.5% by weight of gelatin, 0.25% by weight of monosodium glutamate. The resulting mixture is impregnated with air to obtain a foamy suspension containing up to 30% by volume of air and poured onto trays in layers 10 mm thick. The mixture is cooled to -55 ° C for 3 hours and then dried by a sublimation procedure, with an initial drying temperature of -40 ° C and a final temperature of 45 ° C. The drying time is 10 hours.

The result is 10.5 kg of a dry bacterial preparation for the preparation of raw sour milk cheese, processed creams and buttermilk. 1 g of dry bacterial preparation contains 600 billion lactic acid bacterial cells.

1 g of dry bacterial preparation acidifies 300 liters of milk in 10 hours. The acidity of the coagulate obtained is 78 ° T. The product obtained using the present preparation does not differ from the normal product 11 66196 in terms of organoleptic and microbiological properties.

Example 2 400 g of sodium citrate are added to 100 l of skim milk and 12 kg of dried skim milk are dissolved in it with a dry matter content of 18.3% by weight of the mixture.

The resulting mixture is placed in a fermentor, sterilized at 121 ° C for 20 minutes and cooled to 40 ° C. To this medium is added 3.3 kg of a culture of acidic bacteria, Lactobacterium acidophilum, species Ep-2, cultured in sterile skim milk. The resulting mixture is mixed thoroughly and the culture is continued at 40 ° C for 4 hours. During this time, the pH of the broth reaches 4.1.

To the medium are added 6 l of sterile, 50% aqueous sodium acetate solution, 1 liter of sterile, condensed corn steep liquor, 100 ml of sterile 0.3% vitamin solution and 100 ml of sterile 0.1% manganese sulfate solution, and all the above substances are mixed thoroughly.

Acidophilic bacteria are cultured in this medium at 40 ° C for 12 hours.

During this time, the acidity of the broth reaches a value of 350 ° T and a pH of 3.9.

To the liquid bacterial preparation is added 100 ml of a sterile 0.01% solution of zymase and the preparation is cooled to 8 ° C.

The resulting liquid bacterial preparation is mixed with 12 l of a sterile preservative containing 2 kg of sugar and 400 g of sodium acetate.

The mixture is mixed thoroughly, saturated with air to 50% by volume, poured into trays in layers 10 mm thick and frozen in a freezer at -50 ° C for 1.5 hours.

The frozen mixture is then transferred to a chamber-type sublimation apparatus and dried under the following conditions: initial temperature -30 ° C, final temperature 45 ° C, drying time 24 hours.

The result is 38 kg of a dry bacterial preparation of acidophilic bacteria, with 1 g of preparation containing 2500 million bacterial cells. The anbiotic effect of the preparation is high.

The dry bacterial preparation 12 661 96 containing acidophilic bacteria is regenerated for use in the meat industry by adding water. For example, 114 g of boiled water cooled to 45 ° C is added to 38 kg of dry bacterial preparation. The preparation mixed with water is stirred and kept at room temperature for 2 hours. The regenerated preparation has an acidity of 360 ° T and a pH of 4.1.

The amount of dry bacterial preparation obtained is intended to be added to 15.2 tons of sausage filling in the cutting process.

Differences in the following characteristics were observed between the sample sausages prepared according to the present method and the reference sausages prepared according to the known method on day 17 of drying:

Feature

Experiment Comparison pH 5.1 5.6

Lactic acid,% by weight 0.923 0.719

Titrated acidity (when converted to propionic acid),% by weight 0.589 0.469 This means that the method of preparation used increases the amount of organic acids, lowers the pH and thus improves the health of the product in a shorter drying time than is usually obtained with the conventional method for making smoked sausages. The organoleptic properties of the product obtained with the use of the preparation are also improved.

The product prepared with the help of a dry bacterial preparation is ready in 17 days. This gives a great financial advantage.

Example 3 1600 kg of sodium citrate and 40 kg of skimmed milk powder are added to 400 liters of skim milk, the dry matter content of the mixture being 16.3% by weight. The resulting mixture is placed in a fermentor, sterilized at 121 ° C for 20 minutes and cooled to 40 ° C. To the obtained medium is added 8 l of a culture of acidophilic bacteria (Lac-tobacterium acidophilum, species Ep-2), the mixture is mixed thoroughly and cultured at 40 ° C for 5 hours. During this time, the pH of the broth reaches 4.5. To this broth is added 24 l of a 50% aqueous solution of sodium acetate, 4 l of sterile corn steep liquor, 400 ml of a sterile solution of vitamin B ^ 0.3% and all these are mixed thoroughly. Culturing of acidophilic bacteria in this medium is continued at 40 ° C for 14 hours. The acidity of the broth reaches 480 ° T and a pH of 3.8. Zymiasis is then added to this liquid bacterial preparation and cooled to 6 ° C.

The resulting liquid bacterial preparation is mixed with 40 l of a sterile preservative containing 8 kg of sugar and 1.6 kg of sodium acetate. The mixture is mixed thoroughly, saturated with sterile air to 20% by volume and dried by a spray-drying procedure. The air temperature at the inlet of the drying chamber is 120 ° C and at its outlet 45 ° C.

The amount of the dry bacterial preparation containing acidophilic bacteria obtained from this amount of liquid bacterial preparation is 164 kg.

Its use is the same as in Example 2.

To this amount of dry bacterial preparation is added 492 L of boiled water cooled to 40 ° C. The preparation is mixed with water and the mixture is kept at room temperature for 2 hours. The acidity of the regenerated preparation is 320 ° T and the pH is 4.5. The amount of regenerated bacterial preparation produced is sufficient for 65.8 tonnes of smoked sausage filler at the cutting stage.

Samples of smoked sausages made from a sausage filling containing this bacterial preparation showed higher lactic acid content and volatile fatty acid content and higher titrated acidity on day 17 of drying than control samples prepared according to known technology. The values obtained are shown in the following table; they show that the maturation of the sample sausages progressed faster.

Property Method of preparation Sample Reference (without bacterial preparation) _ pH 5.2 5.7

Lactic acid,% by weight 0.948 0.755

Volatile fatty acids,% by weight 0.046 0.040

Titrated acidity (when converted to propionic acid) »% by weight 0.586 0.485

Claims (4)

14 66196 A process for the preparation of dry lactic acid bacterial preparations useful in food preparation by culturing lactic acid bacteria at optimum growth temperature in a milk-based medium supplemented with a nitrogen donor, a mixture of buffer and mineral salts, and with a preservative containing buffer salts and drying, characterized in that lactic acid bacteria are cultured in a broth containing: as a milk-based substance a mixture of fresh, skimmed milk and skimmed-milk powder with a dry matter content of 16-20% by weight, or whey is diluted 1: 5 with water and mixed with 1% skimmed milk; as a buffer salt 0.4 to 3.0% by weight of sodium citrate or acetate; as a nitrogen donor and as a source of mineral salts and vitamins 0.5-1.5% by weight of grain extract; and 0.0001 to 0.025% by weight of manganese sulphate as a trace element, the culturing of lactic acid bacteria is carried out, optionally neutralizing the medium; the cooled liquid bacterial preparation and the preservative are mixed in a ratio of 1: 0.1 to 1: 4, and the mixture is saturated with sterile air before drying, which is used to obtain a 20-50% by volume foamy suspension. Process according to Claim 1, characterized in that the lactic acid bacterium Streptococcus laetis, Streptococcus acetoinicus, Streptococcus cremoris or a combination thereof or Lactobacterium aeidophilum is cultured. Process according to Claim 1, characterized in that, when an acidophilic bacterial culture is used as the inoculum, the cereal extract and manganese sulphate are added to the medium at a pH of 4.1 to 4.8, while 3.0% by weight of sodium acetate is added thereto, and 0.0003% by weight of vitamin B12, and at the end of the culture, at a pH of 3.5-3.9, 0.01% by weight of zymase is added to the liquid bacterial preparation, after which the mixture is cooled to 6-10. ° C. Process according to Claim 1, characterized in that the preservative contains 2.3 to 2.5% by weight of sucrose; 2.0-5.0% by weight of skimmed milk powder; 1.5% by weight of sodium citrate; 1.5% by weight of gelatin; 0.25% by weight of sodium glutamate and the rest of the water, and when an acidophilic bacterial culture is used as the inoculum, the preservative contains 20% by weight of sucrose, 4% by weight of sodium acetate and the rest of the water. 16,661 96