The monitoring of microbial populations in the moravian wines

abstract

English

Winemaking can be summarized as the biotransformation of must into wine, which is carried out principally by Saccharomyces cerevisiae strains during the primary, i.e. alcoholic, fermentation. A secondary fermentation, the so-called malolacticfermentation(MLF), assures biodeacidification that is also often encouraged, since it improves wine stability and quality. Malolactic fermentation usually takes place after alcoholic fermentation, but may also occur simultaneously with the primary fermentation. During the fermentation, lactic acid bacteria metabolize malic acid to form lactic acid and CO2. Strain of lactic acid bacteria isolated from wine belong to the genera Lactobacillus, Oenococcus and Pediococcus, although MLF is largely controlled by Oenococcus oeni. The aim of presented work was to monitor the relationship between malolactic fermentation and activity of wine yeasts. Total number of lactic acid bacteria and yeasts occurring in grape must during wine production was evaluated. The study was performed on the red wine grape variety Cabernet Moravia from organic vineyard and on the white wine grape variety Sauvignon from both organic and integrated vineyards. The isolation of pure cultures of lactic acid bacteria from mixed microbial cultures and subsequently their identification by genus and species-specific PCR was also subject of the thesis. The experimental results show that the number of colony forming cells of lactic acid bacteria is influenced not only by the wine grape variety, whether it is a variety of red or white wine grape, but also by the way of wine growing. The method of wine growing also had an impact on the species representation of lactic acid bacteria in each variety.

wine, lactic acid bacteria, organic and integrated vineyards, malolactic fermentation, polymerase chain reaction

VALICOVÁ, M.; OMELKOVÁ, J.; ŠPANOVÁ, A.; TRACHTOVÁ, Š.

2. 5. 2012

Bratislava 2012

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