Potential for enrichment of kombucha with encapsulated probiotic strain Lactobacillus rhamnosus

Kombucha is a traditional beverage of Asian origin, usually prepared by fermenting sweetened black tea (Camellia sinensis L.) using a symbiotic consortium of acetic acid bacteria (AAB) and osmophilic yeasts (Symbiotic Consortium of Bacteria and Yeast - SCOBY). Kombucha exhibits several functional properties such as antimicrobial, antioxidant, antiproliferative, etc., however it usually cannot be labeled as a probiotic product since the number of probiotic microorganisms often does not reach the specified criteria of 6-8 log CFU/mL. Lactic acid bacteria (LAB) are one of the major bacteria used for probiotic purposes. Lthat exert health benefits should be able to survive sometimes harsh conditions during fermentation, processing and storage. Several microencapsulation methods are already being used to improve their viability in various matrices. In this study, the probiotic strain Lactobacillus rhamnosus ATCC 53103 was encapsulated in maltodextrin and pea protein using three different sample preparation methods prior to encapsulation by lyophilization. Based on encapsulation efficiency, method 3 was selected as the most effective and applied for further encapsulation using three additional carriers, two polysaccharides (pectin and inulin) and one protein (whey). The dissolution behavior, LAB viability and release kinetics of the obtained capsules was then investigated in different media (physiological saline, sodium citrate, and KH₂PO₄). The results indicated that physiological saline provided the most stable conditions. Finally, the stability of encapsulated Lwas evaluated in finalized kombucha during storage. Among the tested carriers, whey protein showed the best ability to protect Lcells and maintain their viability, although its stability was limited to 10 days. In other carriers, Lsurvival was significantly reduced.