ANALYSIS OF BILE SALT RESISTANCE IN LACTOBACILLUS ISOLATED FROM ICE CREAM

Probiotics are beneficial living microorganisms that can be present in various foods. One is ice cream, a dairy product that can be a food carrier for probiotic bacteria, with Lactobacillus being one of the most prevalent species. Ice cream is a functional and nutritious food that contains valuable components such as dairy, vitamins, and minerals, making the presence of Lactobacillus in ice cream particularly advantageous. The main objective of the research is to offer consumers food that is not only rich in nutritional value but also provides additional probiotic advantages by identifying the Lactobacillus presence and evaluating its resistance to bile salts. In this specific investigation, five ice cream samples from local sources were cultured on a medium formulated specifically for Lactobacillus growth. Following biochemical tests to confirm the existence of Lactobacillus, the samples displayed characteristics such as being Gram-positive, catalase-negative, acid-fast-negative, and endospore-negative. The confirmed Lactobacillus colonies were then subcultured in nutrient broth to analyse bile resistance. The resistance of Lactobacillus to three different concentrations of bile salts (0.1%, 0.2%, and 0.3%) was also evaluated using spectrophotometry at 600 nm. Under control conditions, all samples demonstrated moderate to high growth. Statistical analysis revealed that the differences in bacterial growth across various bile salt concentrations were not statistically significant (p-value > 0.05). Taken together, findings of this study indicates Lactobacillus bacteria isolated form the ice cream samples are resistance to bile salts, underscoring the advantage of utilizing Lactobacillus bacteria to deliver probiotic benefits to consumers. Keywords: Ice Cream, Probiotics, Lactobacillus, Bile salt resistance