Evaluation of the in vitro probiotic properties of Ligilactobacillus salivarius JCF5 and its impact on Jersey yogurt quality.

BACKGROUND: Jersey milk, known for its high protein content, is an excellent base for yogurt production. Given that Jersey milk is derived from Jersey cows, this study was to isolate probiotics from Jersey cow feces and investigate their potential as alternative starter cultures for fermenting Jersey milk. Our goal was to develop new starter cultures specifically suited for Jersey yogurt production, while also contributing to the diversity of fermentation agents available for dairy products. This study aimed to evaluate the probiotic functions of Ligilactobacillus salivarius isolated from the feces of newborn Jersey calves after colostrum consumption and to investigate its impact as a starter culture on the quality of Jersey yogurt.

RESULTS: A lactic acid bacterial strain was screened through acid and bile salt tolerance tests and simulated gastrointestinal experiments. The strain survived up to 42.8% after 3 h of cultivation at pH 2, and its viable count after 3 h of cultivation in a medium containing 0.3% bile salt was 3 log(CFU mL-1). Additionally, the survival rates after 3 h of treatment with gastric and intestinal juices were 90.67 ± 0.41% and 84.97 ± 1.40%, respectively, indicating good acid and bile salt tolerance. Identification using 16S rDNA showed that the strain was L. salivarius JCF5. This strain improved the texture properties such as viscosity, elasticity and cohesiveness of yogurt when used in combination with commercial starter cultures.

CONCLUSION: Ligilactobacillus salivarius JCF5 is a promising probiotic strain for enhancing the quality of Jersey yogurt. © 2025 Society of Chemical Industry.