Bacteriophages of Lactic Acid Bacteria

Bacteriophages harm food production, disrupt fermenting, spoil dairy products, and cause financial loss. The article describes the biodiversity and properties of bacteriophages capable of lysing lactic acid bacteria used in fermented dairy and meat products. The research featured bacteriophages obtained from fermented meat and dairy products. The methods included microbiological analyses, sensory evaluation, physico-chemical tests, genetic studies, electron microscopy, optical reassociation, and mathematical data processing. Violation of the fermentation process always resulted in bacteriophages in the finished products, e.g., fermented dairy products, curd whey, raw smoked and dry-cured sausages, etc. The list of bacteriophages of lactic acid bacteria included 20 bacteriophages of Lactococcus ssp., 11 – of Streptococcus salivarius subsp. thermophilus, and 5 – of Lactobacillus delbrueckii subsp. bulgaricus. The study revealed the diversity of the isolated bacteriophages, their molecular and biological profile, the titer and range of their new hosts, and the differences from standard ones. The bacteriophages proved to be able to infect a wider range of lactic acid bacteria. The article describes the change in the biodiversity and evolution of bacteriophages depending on their lytic action and virulence. The improved collection of bacteriophages and their detection cultures contribute to an earlier and more effective identification of bacteriophages in fermented products.