Optimization of physicochemical and antimicrobial properties of functional kombucha beverage sweetened with dried fruits using simplex centroid mixture and Plackett-Burman designs.

Traditional foods and beverages represent alternative strategies to counteract bacterial virulence. The fermentation of tea, sugar, supplemented with a symbiotic culture of bacteria and yeast (SCOBY) produces kombucha beverage, which offers several health advantages and is similar to soft drinks. This study investigates the effect of various fermentation factors on the growth levels of Lactobacillus, Lactococcus, total phenolic content and antimicrobial activities of Green Tea, Black Tea and Moringa kombucha beverage (GTBTMK) prepared with a starter SCOBY culture. Formulation of kombucha beverage was optimized using a Simplex-Centroid Mixture Design and Plackett-Burman Design. The best optimized kombucha formulation (18.98 g/L; Dried Apricot was 20 g/L; Dried plum was 10 g/L, Dried Grape was 20 g/L,11.763 g/L Green tea, 0.01238 g/L Black tea and 8.1127 g/L Moringa) contain a high phenolic content of 86.79 mg GAE/mL and exhibited a significant antimicrobial activity against Bacillus cereus ATCC 11778, Micrococcus luteus NCIMB 8166 and Enterococcus faecalis ATCC 29212, Candida albicans ATCC 90028, Cryptococcus neoformans ATCC 14116, Aspergillus brasiliensis ATCC 16404 (Inhibition zone more than 20 mm). This research provides new insights into the development of innovative, functional kombucha beverage potentially expanding the spectrum of health-promoting fermented drinks available to consumers.