Kombucha is a fermented beverage produced using a symbiotic consortium of acetic acid
bacteria and yeasts, often marketed for its health-promoting properties. However,
probiotic bacteria in kombucha are typically present at inconsistent levels and may
not remain viable during fermentation. In this study, three Lactobacillus strains
(Lacticaseibacillus rhamnosus ATCC 53103 (L. rhamnosus), Lactiplantibacillus plantarum
subsp. plantarum ATCC 14917 (L. plantarum) and Lentilactobacillus hilgardii (L. hilgardii)
isolate) were encapsulated in whey protein using the lyophilization method and added
individually at the start of kombucha fermentation. Lactic acid bacteria (LAB)–enriched
kombucha samples were evaluated for chemical composition (polyphenols, flavonoids,
vitamin C and organic acids) and functional properties (antimicrobial, antiproliferative,
antioxidant and anti-inflammatory activities) and compared to a traditionally obtained
control kombucha, primarily demonstrating in vitro and experimental assessment. Encapsulation
maintained LAB viability above 6–7 log CFU/mL throughout fermentation, producing kombucha
with enhanced microbial stability. LAB–enriched samples exhibited increased L-lactic
acid and antimicrobial activity. L. rhamnosus and L. hilgardii–enriched samples exhibited
increased antiproliferative and anti-inflammatory activities, which may be associated
with strain-dependent production of organic acids, polyphenol modulation and LAB-derived
bioactive metabolites. Antioxidant activity varied depending on assay, and L. rhamnosus–enriched
kombucha showed higher anti-inflammatory activity. These findings demonstrate that
whey protein encapsulation can preserve LAB during fermentation, enhance specific
bioactive properties and provide a platform for developing functional kombucha beverages
with potential applications in the food industry.
