RU2084161C1 - Method of bacterial enzyme preparation preparing - Google Patents

Abstract

FIELD: dairy industry. SUBSTANCE: symbiosis of mesophilic lactic acid bacteria Streptococcus lactis, Streptococcus cremoris and Sreptococcus diacetylactis were cultured for 48 h with proteins isolated from the whey by ultrafiltration method. In the process of culturing deoxidation of protein concentrate is carried out four-fold: after 6, 12, 24 h - to pH = 6.5; after 48 h - to pH = 5.4, or once after 48 h - to pH = 5.4. Simultaneously with bacterial symbiosis culturing the protein concentrate is hydrolyzed with proteolytic enzyme. To maintain pH value at optimal level buffer capacity of the protein concentrate is increased by addition of trisodium citrate. The obtained bacterial enzyme preparation has significant amount of lactic acid streptococcus mesophilic cells and easily assimilating protein catabolites as compared with the known methods. EFFECT: improved method of preparing, enhanced biological quality. 3 cl, 1 tbl

Description

 The invention relates to the dairy industry, in particular the production of bacterial preparations.

A known method for producing a bacterial protein preparation using proteins isolated from whey. Protein mass isolated from whey is fermented with leaven, including viscous varieties of mesophilic lactic acid and acetic acid bacteria Str. lactis 121, Str. cremoris 8II, Str. acetoinicus H ₄₀ , Str. thermophilus 151, Acetobacter aceti RD 10, taken in a ratio of 2: 1: 2: 2: 1. The fermented protein mass is deoxidized and then spray dried. The finished bacterial preparation is used as a bacterial starter culture and protein filler in the production of fermented milk products. This method is in technical essence closest to the proposed one.

 The disadvantage of this method is the low efficiency of the resulting preparation, namely, a comparatively small number of lactic acid bacteria cells, low content of easily digestible protein and lactose breakdown products. In addition, protein bacterial preparations were not used in the production of hard rennet cheese.

 The proposed method allows to increase the number of lactic acid bacteria cells in a bacterial protein preparation, to increase the content of easily digestible protein and lactose breakdown products in it, and also to expand the field of application of the bacterial protein preparation.

 According to the invention in a method for producing a bacterial-enzyme preparation, comprising culturing bacterial symbiosis of Str. lactis, Str. cremoris on proteins isolated from whey, deoxidation of fermented protein mass, cultivate a symbiosis of mesophilic bacteria Str. lactis, Str. diacetylactis, which are part of the bacterial preparation BP-6, for 48 hours, and deoxidation is carried out four times after 6, 12, 24 and 48 hours, and after 6, 12, 24 hours to pH6.5, and after 48 hours to pH 55 , 4, or once after 48 hours to a pH of 5.4. Simultaneously with the cultivation of bacterial symbiosis, the whey protein concentrate is hydrolyzed by a proteolytic enzyme, for example, protosubtilin G10X.

 The proposed method is as follows.

The purified whey is pasteurized, cooled to a temperature of 50 ± 2 ^o C and sent to ultrafiltration, then the resulting protein concentrate is pasteurized, cooled to a temperature of 30 ^o C and make the activated preparation BP-6 in an amount of 5 wt. Fermentation is carried out for 48 hours, after 6, 12 and 24 hours, the protein mass is deoxidized with a 20% Na ₂ CO ₃ solution to a pH of 6.5, and after 48 hours to a pH of 5.4. Simultaneously with the cultivation of bacterial symbiosis, the whey protein concentrate is hydrolyzed using a proteolytic enzyme, for example, protosubtilin G10X, in an amount of 0.1 wt.

 The proposed method is illustrated by the following examples.

 Example 1

1000 kg of fresh cheese whey is heated in the regeneration section of the plate pasteurization-cooling unit to a temperature of 40 ± 2 ^o C and purified from milk fat and casein dust on a self-unloading separator. The purified whey is pasteurized at a temperature of 72 ± 2 ^o C with an exposure of 15 -20 ^o C, cooled to a temperature of 4 ± 1 ^o C and sent to intermediate storage for no more than 6 hours. The cooled serum is heated to a temperature of 50 ± 1 ^o C and sent for ultrafiltration in order to obtain a whey protein concentrate. The ultrafiltration process is carried out on special A1-OMS plants using semi-permeable membranes with an average pore diameter of 40 ± 4 nm. The resulting protein concentrate is pasteurized at a temperature of 85 ± 2 ^o C with a holding time of 5 minutes, cooled to 30 ^o C and introduced into it protosubtilin G10X in an amount of 0.1 wt. and an activated bacterial preparation BP-6 for small rennet cheeses in an amount of 5 wt. The protein concentrate is acidified for 48 hours, and after 6, 12 and 24 hours it is deoxidized with a sterile 20% Na ₂ CO ₃ solution to a pH of 6.5. After 48 hours, the fermented protein mass is deoxidized to a pH of 5.4 and sent to produce cheese.

 Example 2

Analogously to example 1, while to the protein concentrate add sodium citrate trisubstituted in an amount of 1.5 wt. The protein concentrate is pasteurized at a temperature of 85 ^o C with an exposure of 5 minutes, cooled to 30 ^o C and make protosubtilin G10X in an amount of 0.1 wt. and an activated bacterial preparation BP-6 in an amount of 5 wt. The protein concentrate is fermented for 48 hours. The fermented protein mass is deoxidized to a pH of 5.4 and sent to the production of cheese.

 Example 3

Analogously to example 1, the fermented mass is deoxidized to a pH of 5.4 and dried on a disk spray dryer with a temperature in the spray zone of not more than 50 ^o C.

 The results of the examples are given in table. one.

 Protein concentrate obtained by ultrafiltration of whey contains all the substances necessary for the development of lactic acid bacteria: protein nitrogenous compounds, free amino acids, vitamins, and a complex of microelements.

 When using protein concentrate as a nutrient medium for the accumulation of mesophilic lactic acid bacteria Str. lactis, Str. cremoris and others according to the prototype, the number of cells after 72 hours of cultivation is 2.2 3.7 billion / g, the content of non-protein nitrogen compounds 16.3 18.1 mg% (table 1. Prototype).

 The vital activity of microorganisms is possible only within certain pH ranges. So, the optimal reaction of the environment under which the development of mesophilic lactic streptococci, which are part of the bacterial preparation BP-6, is pH 5.5 6.5. With a decrease in pH to 4.75, the development of lactic acid bacteria is delayed, and then their death begins.

Adjusting the pH during the cultivation of bacterial symbiosis on proteins isolated from whey by 4-fold deoxidation by adding a 20% solution of Na ₂ CO ₃ after 6, 12, 24 and 48 hours allows you to increase the number of cells to 3.7 6.3 billion / g, and the content of non-protein nitrogen compounds up to 18.9 22.5 mg%
It is known that some peptides and amino acids enhance the growth of lactic acid bacteria. In order to convert proteins into forms more accessible for the growth of lactic acid bacteria (peptides and amino acids), the protein concentrate was hydrolyzed with protosubtilin G10X, the enzyme and the bacterial preparation BP-6 being administered simultaneously. The number of cells in this case reached 9.5 to 22 billion / g, and the content of non-protein nitrogen compounds 22.0 to 22.9 mg% (example 1).

 For the development of microorganisms, the buffer properties of the medium are of great importance. It is known that such buffer salts as sodium citric, phosphoric and acetic acids favorably influence the growth of lactic acid bacteria. The strongest stimulating effect on dairy streptococci (especially aroma-forming) is exerted by trisodium sodium citrate.

 When growing mesophilic lactic streptococci on protein concentrate with the addition of 1.5 wt. sodium citrate and 0.1 wt. protosubtilin G10X cell content is 4.5 5.5 billion / g, and non-protein nitrogen-containing compounds 66.5 68.5 mg% (example 2).

 Obtained according to the invention, the bacterial-enzyme preparation can be used immediately after deoxidation or dried.

 When dried, the lactic acid bacteria lose moisture and pass into the state of inactive cells, which, under favorable conditions, again return to the active state. Bacteria in an inactive state are characterized by increased resistance to external adverse conditions. Dry bacterial-enzyme preparation has good solubility and fairly good activity, which lasts for 2 to 3 months. 1 g of dry bacterial-enzyme preparation contains 36.3 40.9 billion / g of mesophilic lactic streptococcus cells, 179.6 388.5 mg% non-protein nitrogen compounds (example 3).

 Thus, the claimed method allows to obtain a bacterial-enzyme preparation of high biological value, containing a significant number of cells of mesophilic lactic streptococci and easily digestible protein breakdown products in comparison with known methods (prototype).

Claims (3)

 1. A method of obtaining a bacterial-enzyme preparation, comprising cultivating bacterial symbiosis, including Streptococcus lactis and Streptococcus cremoris, on concentrated and pasteurized protein concentrate isolated from whey, deoxidation of the obtained fermented mass, characterized in that the bacterial symbiosis further comprises Streptococcus diacetylact lead for 48 hours with simultaneous enzymatic hydrolysis of the whey protein concentrate with a proteolytic enzyme, deoxidation of protein m the sc is carried out in the process of ripening four times after 6, 12, 24 and 48 hours, and after 6, 12 and 24 hours the process is carried out to pH 6.5, and after 48 hours to pH 5.4 or once after 48 hours to pH 5, 4.  2. The method according to claim 1, characterized in that before pasteurization, sodium trisubstituted sodium citrate is added to the whey protein concentrate, the deoxidation being carried out once after 48 hours to a pH of 5.4.  3. The method according to p. 1, characterized in that after deoxidation, the protein mass is dried by spraying to obtain a bacterial-enzyme preparation.

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