[Comparison of methods of storing lactic acid bacteria]

The study was undertaken to elucidate how different methods of storage (immersing in mineral oil, lyophilization, and subculturing) of lactic acid bacteria belonging to the genera Lactobacillus and Lactococcus affect their viability, antibiotic activity, and ability to accumulate organic acids. Storage of the lactic acid bacterium L. lactis subsp. lactis by immersion in mineral oil proved to be ineffective. Lyophilization allowed the survival of a sufficiently large number of cells, although their antibiotic activity somewhat decreased. The resuscitation of lyophilized bacteria by subculturing them in rich nutrient media, such as skim milk, led to the restoration of their physiological activity, including the effective antimicrobial spectrum.