SCREENING OF EXOPOLYSACCHARIDE-PRODUCING STRAINS OF LACTIC ACID BACTERIA FOR USE IN FOOD BIOTECHNOLOGY

The article presents the results of studying the technological properties and the ability to synthesize exopolysaccharides of lactic acid bacteria isolated from domestic traditional fermented milk products. The strains were identified using the MALDI-TOF MS and API 50CHL methods. All tested strains showed the ability to grow in milk. After 24 hours of incubation, they formed a homogeneous, dense consistency, reminiscent of yogurt, and had a pleasant aroma characteristic of fermented dairy products.
It should be noted that, according to technological parameters, the strains Lactobacillus acidophilus 3.7 and Lactobacillus acidophilus 3.10 demonstrated the best results: the total number of cells was 3.6 ± 2.3 × 10⁸ and 1.8 ± 4.0 × 10⁹ CFU/ml, respectively, and the pH values were 3.6 and 3.7. It was found that of the nine cultures studied, eight strains showed positive exopolysaccharide – producing activity. These strains were selected for the subsequent assessment of probiotic properties for their use in further research.
According to the results of the screening, it was shown that the Lb strain, paracasei 4.2, showed high exopolysaccharide-producing activity.

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