Burtseva G. Biological properties of meat fermenting bacteria.

The thesis deals with the study of biological properties of active meat fermenting bacterial strains and estimating efficiency of the preparation elaborated on their basis in dry-cured products manufacturing. The microflora composition of artisanal fermented meat products is investigated. Some strains belonging to the genera Staphylococcus and Lactobacillus were recognized as promising from the point of view of their meat fermenting properties, such as salt resistance, proteolytic, catalase and nitritreductase activities, antagonistic activity against pathogenic microorganisms, inability to toxinproduction, absence of resistance of antibiotics. Relationship between promising strains of coagulase-negative staphylococci and lactobacilli is defined. It is shown that combination in сomposition such starter cultures as L. plantarum ІМВВ 3200, L. casei subsp. rhamnosus ІМВВ 3303, S. simulans ІМВВ 5300 increases their viability. Mechanisms of development of the strains are investigated. Optimal conditions for their biomass accumulation and their viability preservation are processed. A new meat starter bacterial preparation named "MKC" is elaborated. It contains not less than 1010 CFU lactobacilli and 108 CFU staphylococci per 1 g of the substance. It's found that applying "MKC" preparation in manufacturing of dry-cured ham and beef reduces the work cycle time for 3-4 days. It guarantees excellent organoleptic characteristics and provides a high level of safety of the product: absence of pathogenic microorganisms, low levels of residual nitrites.