Yeast isolated from grape marcs for Grappa


TITOLO: Yeast population dynamics during pilot-scale storage of grape marcs for the production of Grappa, a traditional Italian alcoholic beverage

RIVISTA: International Journal of Food Microbiology

NUMERO RIVISTA: n. 129, p. 221-228

The composition and population dynamics of the yeast microflora of grape marcs were investigated during a pilot scale fermentation study using two white grape varieties, namely Moscato and Prosecco, from two distinct areas of the Veneto Region. Yeast counts were made at the beginning, after 4 and after 15 days of marc storage under anaerobic conditions. Seventy isolates from each sampling time were identified to species by RAPD-PCR analysis and subsequent ITS region sequencing. A good biodiversity of yeasts occured in both marcs at the beginning of fermentation, with high presence of Hanseniaspora opuntiae, but without detectable presence of Saccharomyces strains, which instead became the dominant yeast after just 4 days of fermentation, remaining at that level until the end of fermentation. Colonization of Moscato marc by S. cerevisiae resulted better, in relation to its higher sugar content. Characterization of S. cerevisiae isolates by mitochondrial DNA restriction analysis revealed the presence of 66 different strains in the marc from the Moscato grapes, without the occurence of a clearly dominant strain, while in the marc from Prosecco grapes only 23 different profiles were scored, with a dominant strain that accounted for 62.7% of the Saccharomyces population after 4 days of fermentation.

AUTORI:  Bovo B., Andrighetto C., Carlot M., Corich V., Lombardi A., Giacomini A.




Articoli simili