Microbial Succession and Flavor Production in the Fermented Dairy Beverage Kefir

• DOI: 10.1128/msystems.00052-16
• Publication Date: 2016-10-05T02:28:47Z
• Authors: Aaron M. Walsh; Fiona Crispie; Kieran Kilcawley; Orla O’Sullivan; Maurice G. O’Sull...; Marcus J. Claesson; Paul D. Cotter
• Keywords: Kefir; Acetic acid bacteria

Kefir is a putatively health-promoting dairy beverage that produced when kefir grain, consisting of consortium microorganisms, added to milk initiate natural fermentation. Here, detailed analysis was carried out determine how the microbial population, gene content, and flavor three kefirs from distinct geographic locations change over course 24-h fermentations. Metagenomic sequencing revealed Lactobacillus kefiranofaciens dominant bacterial species in during early stages fermentations but Leuconostoc mesenteroides became more prevalent later stages. This pattern consistent with an observation genes involved aromatic amino acid biosynthesis were absent L. present mesenteroides. Additionally, these shifts community structure, associated pathways, corresponded changes levels volatile compounds. Specifically, Acetobacter spp. correlated acetic acid; carboxylic acids, esters ketones; 2,3-butanedione; Saccharomyces esters. The correlation data suggest causal relationship between taxa supported by observations addition NCFB 2797 increased ketones whereas 213M0 2,3-butanedione. Finally, we detected probiotic functionalities microbiome. Our results illustrate dynamic nature succession patterns therein can be applied optimize fermentation processes, flavors, health-related attributes this other fermented foods. IMPORTANCE Traditional foods represent relatively low-complexity environments used as model communities understand microbes interact environments. therein. In process, link individual species, compounds several could responsible for purported gut health-associated benefits consuming are identified. Ultimately, providing important fundamental insight into interactions, information