Analysis of microbial diversity and dynamics during wine fermentation of Grenache grape variety by high-throughput barcoding sequencing

• Bacteria and yeast on Grenache wine were analyzed by high-throughput sequencing.
• Rhodospirillales and Lactobacillales were the most abundant bacterial taxa.
• Hanseniaspora, Candida and Saccharomyces were the dominant yeasts.
• High-throughput sequencing is useful to monitor microbial dynamics during fermentations.

Understanding the diversity and evolution of microorganisms during wine fermentation is essential for controlling its production. Previous studies have been primarily based on culture-dependent methods but recent incorporation of culture-independent molecular methods is showing a quite different view of microbial composition and diversity during the wine making process. Herein we applied barcoded pyrosequencing technology to monitor bacterial and yeast dynamics during laboratory scale spontaneous wine fermentation from Grenache variety. Members of the lactic acid bacteria (LAB) and acetic acid bacteria (AAB) were the most abundant, representing the orders Lactobacillales and Rhodospirillales more than 70% of the bacterial population. Other bacterial genera, not previously detected at the end of fermentation, were present in low proportion and their possible role remains unknown. Within the yeast community, the genera Hanseniaspora and Candida were dominant during the initial and mid fermentation while the final fermentation was mainly dominated by Candida and Saccharomyces. This study contributes to the knowledge of the microbial dynamics across spontaneous wine fermentation and presents high-throughput sequencing as a useful tool to monitor and evaluate bacterial and yeast diversity and dynamics during wine fermentation.