Effect of freeze-dried kombucha culture on microbial composition and assessment of metabolic dynamics during fermentation. (February 2022)

• Record Type: Journal Article
• Authors: Fabricio, Mariana Fensterseifer; Mann, Michele Bertoni; Kothe, Caroline Isabel; Frazzon, Jeverson; Tischer, Bruna; Flôres, Simone Hickmann; Ayub, Marco Antônio Záchia
• Is Part Of: Food microbiology. Volume 101(2022)
• Publication Date: 2022-02
• Subjects: Kombucha production -- Microbiome -- 16S -- ITS -- Fermented foods -- Sensory analysis; Food Microbiology -- Periodicals; Aliments -- Microbiologie -- Périodiques; Food -- Microbiology; Periodicals; Food -- Microbiology -- Periodicals; Food contamination -- Periodicals; 664.001579
• DOI: 10.1016/j.fm.2021.103889
• Languages: English
• ISSNs: 0740-0020

Abstract

Abstract: Kombucha is a traditional fermented beverage gaining popularity around the world. So far, few studies have investigated its microbiome using next-generation DNA sequencing, whereas the correlation between the microbial community and metabolites evolution along fermentation is still unclear. In this study, we explore this correlation in a traditionally produced kombucha by evaluating its microbial community and the main metabolites produced. We also investigated the effects of starter cultures processed in three different ways (control, starter culture without liquid suspension (CSC), and a freeze-dried starter culture (FDSC)) to evaluate changes in kombucha composition, such as antioxidant activity and sensory analysis. We identified seven genera of bacteria, including Komagataeibacter, Gluconacetobacter, Gluconobacter, Acetobacter, Liquorilactobacillus, Ligilactobacillus, and Zymomonas, and three genera of yeasts, Dekkera/Brettanomyces, Hanseniaspora, and Saccharomyces . Although there were no statistically significant differences in the acceptance test in sensory analysis, different starter cultures resulted in products showing different microbial and biochemical compositions. FDSC decreased Zymomonas and Acetobacter populations, allowing for Gluconobacter predominance, whereas in the control and CSC kombuchas the first two were the predominant genera. Results suggest that the freeze-drying cultures could be implemented to standardize the process and, despite it changes the microbial community, a lower alcohol content could be obtained. Highlights: Freeze-dried starter culture resulted in kombucha with lower content of alcohol. The results suggest that presence of Zymomonas influenced the alcohol content of kombucha. Yeast populations were predominated by Dekkera/Brettanomyces. Fermentation eliminated the presence of Enterobacteriaceae in kombuchas.