Spontaneous fermentation in wine production as a controllable technology

Abstract

This study focuses on the isolation of a consortium of microorganisms from spontaneously fermenting must that naturally contain lactic acid bacteria, non-saccharomyces yeasts, and saccharomyces yeasts. To collect the greatest diversity of microorganisms, the consortium was taken from the point of micro-sparkling. Based on the growth curves, isolation was performed using individual special nutrient media, and the isolates were subsequently multiplied in the nutrient medium. Individual isolates were then used for fermentation tests to monitor the percentage of fermented sugar and hydrogen sulphide production. The highest fermentation abilities were achieved in the isolates containing Saccharomyces cerevisiae and Zygosaccharomyces bailii. The smallest amount of ethanol was formed from the isolates containing Hanseniaspora uvarum, while Candida sake isolate produced the lowest amount of hydrogen sulphide and Zygosaccharomyces bailii produced the highest. The other isolates produced an average amount. Based on these results, a consortium containing the given isolates in a certain ratio was compiled.

Keywords

• spontaneous fermentation
• yeast cultivation
• yeast isolation