Genetic improvement of technological characteristics of starters for fermented milk products

Possibility for improvement of technological characteristics of lactobacilli using mutations of resistance to rifampicin (rif ^r ) and streptomycin (str ^r ) was studied. Using starter model of Narine Lactobacillus acidophilus INMIA-9602 Armenian diet milk product, it was showed that a possibility for selecting strains with increased rate of milk fermentation and acid production is higher in Rif^r and Str^r mutants induced by nitrosoguanidine than in cultures sensitive to antibiotics. The milk products obtained using Rif^r and Str^r strains had high viscosity, improved texture, increased amount of alive cells and good organoleptic features.