EFFECT OF FREEZING ON THE BIOCHEMICAL AND ENZYMATIC ACTIVITY OF LACTOBACILLUS BULGARICUS

The problem of preserving the viability, stability and activity of thermophilic lactic acid bacteria Lactobacillus bulgaricus upon freezing is considered. The effect of different freezing conditions and low-temperature storage on the biochemical and morphological properties and stability of the DNA of L. delbrueckii ssp. bulgaricus has been investigated. Sensory evaluation has been carried out for non-frozen bacterial starter cultures containing L. bulgaricus, and their basic physical and chemical parameters (titratable and active acidity and relative viscosity) have been determined. The influence of low temperature on these parameters has been investigated. The effect of freezing and low-temperature storage on the antagonistic activity of L. delbrueckii ssp. bulgaricus strains has been elucidated. The optimum freezing and storage temperatures for the starters containing L. bulgaricus have been determined.