RU2732592C1 - Method of forming starter for kumiss - Google Patents

Abstract

FIELD: food industry.

SUBSTANCE: invention relates to dairy industry. Method of forming a starter culture for kumiss of pure dry bacterial cultures of lactic acid rods: acidophilus, strain In3, bulgaricus strain Fn, and yeast, strain Sk, involves formation of a primary laboratory starter by adding each strain of dry lactic acidophilus and bulb sticks into separate flasks with sterilized, cooled mare's milk. Thorough mixing, holding in thermostat at 37 °C for one day and addition of mare's milk in an amount required to reduce acidity. Secondary laboratory starter is formed by adding activated strains of acidophilus and bulgaricus in 500 ml of sterilized mare's milk, washing in the same way with yeast from the skewed in the test-tube agar with the same milk by means of a sterile glass stick, thoroughly mixing the mixture, holding it in thermostat at 30 °C. Forming a bulk starter during 10–11 days by refreshing, that is adding freshly produced mare's milk to laboratory starter twice a day, morning and evening, to reduce acidity to 65–70 °T, thoroughly mixing the mixture after each refreshment for 15–20 minutes. Amount of base milk needed to reduce acidity is calculated using a process square. During secondary laboratory leaven formation, a mixture of activated strains of acidophilus and bulgaricus and yeast is first held in a thermostat for one day at temperature of 30 °C to increase acidity, then 6 hours at room temperature and after 16 hours in refrigerator for activation of yeast. And during the starter production, starting from the eighth day, to obtain a stable koumiss flavour and a creamy taste, additional 40-minute kneading is performed daily with acidity of 68–72 °T.

EFFECT: invention simplifies the technological process of forming a bulk starter for kumiss, while preserving its quality.

1 cl, 4 tbl, 1 ex

Description

TECHNICAL FIELD OF THE INVENTION

The invention relates to the dairy industry and makes it possible to form a high-quality industrial ferment for kumiss.

LEVEL OF TECHNOLOGY

A known method of preparing industrial starter culture for kumiss from pure dry bacterial cultures of lactic acid sticks: acidophilic, strain In3, Bulgarian, strain Fn, and yeast, strain Sk, fermenting milk sugar and having antibiotic properties in relation to non-pathogenic E. Coli, B. prodigiosum, B. mesentericum, B. mycoides, B. subtilis (Technological instruction for the production of koumiss [text]: All-Russian Research Institute of Horse Breeding. - Divovo, 2010. - 12 p.) (Hereinafter - Technological instruction, 2010).

For the preparation of industrial starter, we used strains of pure cultures of Bulgarian and acidophilus sticks in dry form, yeast on slant wort agar produced by the All-Russian Scientific Research Institute of the Dairy Industry.

Preparation of primary laboratory starter culture on individual strains of Bulgarian and acidophilus bacilli.

A portion of the dry starter culture of each strain of lactic acid bacteria is introduced into 200 ml of sterilized skimmed cow's milk and placed in a thermostat at 37 ° C for 8-10 hours until a clot forms. The introduction of dry starter culture from a bottle is carried out over a burning spirit lamp, observing the rules of asepsis.

From curdled milk under the action of dry starter culture, each strain of Bulgarian and acidophilus sticks is inoculated into several test tubes with 15 ml of sterilized skim milk, adding 8-10 drops of curd to each. In order to avoid peroxidation and separation of serum, crops on media should be kept in a thermostat at + 37 ° С for at least 12-16 hours.

Preparation of secondary laboratory starter culture.

Yeast is introduced into 500 ml of sterilized mare's milk with a temperature of 30 ° C, washing it off with milk from 2 tubes of slanting agar. In the same milk add 12.5 ml of laboratory starter culture of Bulgarian and acidophilus sticks, mix thoroughly and put in a thermostat for 8-10 hours. During this time, the leaven is mixed several times.

Then the starter culture for the accumulation of yeast is left at room temperature 18-20 ° C for 4-6 hours, then kept in the refrigerator for 24 hours at a temperature of + 4 ° C. After that, they begin to prepare the production starter culture.

Preparation of industrial starter culture.

First, 160 ml of mare's milk is added to the laboratory starter culture. Stir for 15-20 minutes and leave in a thermostat at 30 ° C. For an increase in acidity up to 100 - 120 ° T).

To speed up the process of forming a production starter culture, it is recommended to process freshly obtained mare's milk with ultraviolet radiation with an intensity of 180-240 microns for 20 minutes. And the forming mixture should be influenced by a field of centrifugal forces 2 times a day before refreshing for 20 minutes at 2000 rpm.

The subsequent formation of the starter culture is carried out with the addition of freshly obtained mare's milk, reducing its acidity to 65-70 ° T. And building up the acidity of the mixture to 100-120 ° T.

The addition of each portion of mare's milk to the sourdough should be followed by 15-20 minutes of kneading. The starter culture should be refreshed 2 times a day: in the morning and in the evening.

For the formation of kumis aroma and fermented milk taste in the ferment, on the 7-8th day, its refreshing with freshly obtained mare's milk is carried out to 60 ° T with 15-20 minutes of kneading, and upon reaching 70-72 ° T, 30-40 minutes of kneading is carried out.

A ready-to-use starter culture should have a rate of acidity increase from 9 to 11 ° T per hour, a well-defined kumis aroma with a creamy taste.

An indicator of good activity of the starter culture is foaming during maturation and, especially, when stirring.

The ready-made starter culture with an acidity of 120-140 ° T is put into production, refreshing it with freshly obtained mare's milk every day 2-3 times a day to 60-70 ° T until it loses its activity. Additional kneading should be done two to three times a week to improve flavor and aroma.

The temperature of cultivation of an active production starter culture should be above 28-30 ° C.

At least once a month, the starter culture is monitored for antibiotic activity.

The most difficult link in the formation of a production starter culture for kumiss from mare's milk is the stage of preparation of the primary laboratory starter culture, i.e. activation of lactic acid sticks. For this it is necessary to have a laboratory equipped with expensive equipment: an autoclave, bactericidal (ultraviolet) lamps, a thermostat, and a centrifuge. In addition, trained specialists are required who must be able to inoculate pure cultures, prepare media and sterilize them in an autoclave, process freshly obtained mare's milk with ultraviolet radiation and centrifuge the kumis mixture during the formation of the starter culture. All this may not be available to most small kumis farms. And to work with an autoclave, a special permit is required. The use of sterilized cow's milk as a base for sourdough (Technological instruction, 2010) also complicates the process, since not all farms producing kumis have cows. Therefore, cow's milk has to be bought. In this regard, it became necessary to develop a new, affordable and simple method of forming a high-quality industrial starter culture for kumiss.

The closest analogue (prototype) of the invention is a method for preparing a production starter culture for kumiss, which includes all the main technological stages, but differs in that the stage of activating strains of pure cultures of lactic acidophilus and bulgarian sticks was simplified, and the medium was replaced: instead of skim sterilized cow's milk used immediately sterilized mare's milk, poured into flasks of 100 ml each. In this case, the flasks with mare's milk were sterilized in a water bath for 30 minutes, and not in an autoclave. From this it follows that for the preparation of the primary laboratory starter culture, it is sufficient to have a thermostat for keeping the flasks with their contents at a certain temperature for some time and a Turner device to control the acidity of milk under the influence of strains of dry cultures of lactic acidophilus and Bulgarian sticks. The activity of the cultures of acidophilic and Bulgarian sticks was judged by their ability to maintain the acidity of milk within 120 - 164 ° T (Kalashnikova ND Modified method for preparing industrial starter culture for kumiss from dry bacterial cultures [Text] / ND Kalashnikova, A. A. Rodionova // Horse breeding and equestrian sport - 2015. - No. 5.) (hereinafter - the Modified method).

We believe that the use of the proposed invention will greatly simplify and make more accessible, especially for small horse breeding farms, the production of kumis from mare's milk.

DISCLOSURE OF THE INVENTION

When developing the invention, we took a modified method as a basis, but went further along the path of simplifying the method of forming a production starter culture for kumiss, eliminating a number of technological steps: sterilization of cow's milk in an autoclave (Instructions for the preparation and use of starter cultures for fermented milk products at dairy industry enterprises. M., 1978. - 9 p.), Multiple inoculations of cultures with the activation of lactic acid sticks, treatment of mare's milk with ultraviolet light and centrifugation of kumis mixture.

The sterilization of milk in an autoclave disappeared automatically, since we replaced cow's milk with mare's milk.

In addition, it was found that the duration of the bactericidal properties of mare's milk lasts up to 40 hours at a storage temperature of + 4 ° C. After adding sourdough to the stored milk and subsequent kneading, the microorganisms of the Escherichia coli group die completely. Proteolytic and peptonizing bacteria die by 90% (Gladkova E.E. Scientific and practical aspects of improving the methods of processing mares' milk and optimizing symbiotic processes in kumis: abstract of thesis ... Doctor of Agricultural Sciences / E.E. Gladkova - Divovo, 1999 .-- 32 p.).

On the basis of these studies, we excluded the treatment of milk with ultraviolet radiation when forming a ferment for kumiss and in our experiments we used only freshly obtained mare's milk.

Although centrifugation was used to increase the biological activity and growth energy of cultures, which ensured a decrease in the time for the formation of the starter culture, we also abandoned this procedure. We have proved that the quality of the starter culture for kumiss formed by the proposed method does not fundamentally differ from the quality of the starter culture prepared by the modified method.

To test the effect of all these simplifications on the quality of the production starter culture, we formed two starter cultures: control and experimental.

The control production starter culture was formed by the Modified method of kumiss production.

An experimental production starter culture was formed according to the proposed method.

Formation of primary laboratory starter culture.

At the same time, we changed the amount of medium for activating lactic acid sticks from 200 ml of skimmed cow's milk to 1000 ml (1 l) of mare's milk, because at present, portions of the supplied dry starter cultures are designed for addition in 1000 ml.

Sterilization of mare's milk (in the amount of 1 liter in each flask) was carried out in a water bath for 30 minutes. Then each strain of dry lactic acidophilus and bulgarian sticks was introduced into separate flasks with 1 liter of sterilized mare's milk cooled to 30 ° C, thoroughly mixed and placed in a thermostat at 37 ° C for a day. The acidity in the flask with the acidophilus bacillus in a day was 82 ° T, in the flask with the Bulgarian bacillus the acidity was 90 ° T. Mare's milk sterilized in a water bath was added to each flask with cultures, in an amount of 283 and 417 ml, respectively, necessary to reduce the acidity to 65 ° T. On the next day, the acidity in the cultures of Bulgarian and acidophilus rods reached 120-122 ° T, respectively. The amount of mare's milk required to reduce acidity was calculated using the technological square.

Formation of secondary laboratory starter culture.

In 500 ml of mare's milk sterilized in a water bath and cooled to 30 ° C, activated strains of acidophilic and bulgarian sticks with an acidity of 120-122 ° T were added in an amount necessary to provide an acidity of 65 ° T, as well as yeast from two test tubes. The yeast was washed off the agar slant in test tubes with the same milk using a sterile glass rod. The contents were thoroughly mixed and placed in a thermostat for a day at a temperature of 30 ° C to increase the acidity. Then it was kept at room temperature for 6 hours and after 16 hours kept in the refrigerator to activate the yeast.

Formation of production starter culture.

Further formation of the production starter culture was carried out with the addition of freshly obtained mare's milk, without exposing it to ultraviolet radiation, twice a day, reducing the acidity to 65-70 ° T in accordance with the requirements of the Technological instruction, 2010. During formation, the starter culture matured in a thermostat at 30 ° С to acidity of 100-180 ° Т, while we refused to influence it by the field of centrifugal forces 2 times a day before refreshing. Starting from the eighth day, for the formation of kumis aroma and creamy taste in the leaven, an additional 40-minute kneading was carried out daily at an acidity of 68-72 ° T.

Completely both starter cultures - control and experimental were formed on the 12th day. By this time, symbiotic relationships between lactic acid sticks and yeast were established in the starter cultures. Both starters were characterized by a mild creamy taste, a uniform consistency and a stable dense foam.

In the process of forming the starter cultures, the dynamics of changes in the timing and indicators of the energy of acid formation was analyzed, table 1.

It turned out that there were no sharp differences in the nature of the formation of the control and experimental starter cultures, but it should be noted that in the first days of cultivation in the experimental starter culture, the acidification energy was somewhat lower than in the control. However, by the 6th day, the increase in acidity in the test starter culture was practically equal to the acidity indicators of the control starter culture and, later, the acidification energy of the studied starter cultures was approximately equal. In the process of formation, the rate of increase in acidity in both leavens was 9-12 ° T per hour, which indicated the high activity of lactic acid sticks. At the end of the formation period, the maximum acidity slightly decreased in both leavens. This meant that the symbiotic relationship between lactic acid sticks and yeast began to develop more evenly and steadily.

Biochemical studies of the test starter were also carried out. The results of these studies are shown in Table 2.

The biochemical parameters of the experimental starter culture meet the requirements of the standard (Kumys: GOST 52974 - 2008: technical conditions. - Introduced on 13.10.2008. - M .: Standartinform, 2008. - 7 p.) (Hereinafter - GOST, 2008).

The results of microbiological studies of the experimental and control starter cultures are presented in table. 3.

The table shows that both starters do not contain such pathogenic microorganisms as bacteria of the Escherichia coli group and Staphylococcus aureus (S. aureus).

Thus, in a comparative respect, the indicators of the control starter culture practically do not differ from those of the experimental one, which indicates an identical course of biochemical processes.

As our research has shown, the exclusion of a number of technological stages from the method of forming a production starter culture for kumis: multiple inoculations of cultures with the activation of lactic acid sticks, treatment of mare's milk with ultraviolet light and centrifugation of the kumis mixture, did not affect its quality.

CARRYING OUT THE INVENTION

The successful testing of the starter culture formed by the proposed method took place in the experimental kumis shop of the Federal State Budgetary Scientific Institution All-Russian Research Institute of Horse Breeding (hereinafter - FSBSI “All-Russian Research Institute of Horse Breeding”) in 2018, where we began to prepare kumis based on this starter culture. At the same time, milk from kumis mares from the donor horse farm of the All-Russian Research Institute of Horse Breeding is used in the production of kumis.

In the experimental kumys shop of the Federal State Budgetary Scientific Institution "All-Russian Research Institute of Horse Breeding" 2 batches of natural koumiss were produced. The first one is based on the starter culture formed in accordance with the requirements of the Technological Instruction, 2010 (hereinafter - control). The second is based on the leaven formed by the proposed method (hereinafter referred to as the experiment).

Then we investigated the antibiotic activity of starter cultures and kumiss in relation to the B. coli test culture. The B. coli test culture was purchased in the microbiology laboratory of the Federal State Autonomous Scientific Institution "All-Russian Research Institute of the Dairy Industry" and cultivated by us on bacteriological agar.

A visual assessment of the crops of kumis and starter cultures clearly showed a clarified zone of antibiotic activity. This meant that the microflora of starter cultures and kumis suppressed the development of the test culture. The clarification zones were measured in millimeters and their average values were calculated (Table 4).

The zones of growth retardation of non-pathogenic B. coli in the control and experimental starter cultures are on average 27 mm and 27.5 mm (the minimum allowable value is 6 mm). The starter cultures were studied at the same acidity, equal to 140 ° T.

The experimental starter culture and kumis prepared from it practically did not differ from the control in terms of the content of antibiotic substances and had an equally high degree of antibiotic activity.

Kumis, prepared from sourdough according to the proposed method, participated in the competition "For the production of high-quality food products" at the 20th Russian agro-industrial exhibition "Golden Autumn 2018", held in Moscow, and received a diploma and a gold medal.

Thus, our studies have shown that the proposed method of forming a starter culture for kumiss from dry bacterial cultures meets all the requirements of GOST, 2008 and is the most profitable, both in technological and economic aspects, for the development of dairy horse breeding.

Claims (1)

A method of forming a production starter culture for kumiss from pure dry bacterial cultures of lactic acid sticks: acidophilic, strain In3, Bulgarian, strain Fn, and yeast, strain Sk, including the formation of a primary laboratory starter culture by introducing each strain of dry lactic acidophilic and Colgarian sticks into sterilized , chilled mare's milk, thorough mixing, holding in a thermostat at 37 ° C for one day, adding mare's milk in the amount necessary to reduce acidity; the formation of a secondary laboratory starter culture by adding activated strains of acidophilic and Bulgarian sticks to 500 ml of sterilized mare's milk, washing off the yeast from the agar slanted in test tubes with the same milk with the same milk using a sterile glass stick, thoroughly mixing the mixture, keeping it in a thermostat at 30 ° C; formation of a production starter culture within 10-11 days by refreshing, that is, adding freshly obtained mare's milk to the laboratory starter culture twice a day, in the morning and in the evening, to reduce acidity to 65-70 ° T, thoroughly mixing the mixture after each refreshing for 15-20 minutes, while the amount of base milk required to reduce acidity is calculated according to the technological square; during the formation of a secondary laboratory starter culture, a mixture of activated strains of acidophilic and bulgarian sticks and yeast is kept first in a thermostat for one day at a temperature of 30 ° C for an increase in acidity, then 6 hours at room temperature and after 16 hours in a refrigerator to activate the yeast, and during the formation of a production sourdough, starting from the eighth day, to obtain a stable kumis aroma and creamy taste, an additional 40-minute stirring is carried out daily at an acidity of 68-72 ° T.