The study of lactic acid bacteria isolated from natural sources

The quality of the finished fermented milk products largely depends on the activity of bacterial preparations used. Research work aimed at improving composition and properties of the micro ora of bacterial preparations are relevant and in the present time. Isolation of the lactococci strains was carried out from raw milk, naturally fermented milk products and plants. According to the morphological-cultural and physiological-biochemical properties the 56 strains of the isolated microorganisms were classified as: Lactococcus lactis ssp. lactis - 36 %, Lactococcus lactis ssp. cremoris - 41 % and Lactococcus lactis ssp. diacctilactis - 23 %. The study of technologically valuable properties was carried out according to the following criteria: thermoresistances at 65 °C for 30, 60 and 90 min, resistance to different concentrations of salt, sensitivity to antibiotics and phages of lactococci from the collection of the Laboratory of Microbiology. The results of the work were used to make passports for the 22 strains studied.

isolation of microorganisms, lactic acid bacteria, lactococci, starter cultures, technologically valuable properties, antibiotic resistance, phages resistance, thermoresistance, collection fund of microorganisms