Production of aroma compounds by cryotolerant Saccharomyces species and hybrids at low and moderate fermentation temperatures.

摘要

Aim. Among the most important factors influencing wine quality are yeast strains and fermentation temperature. Fermentation at low temperature is presently used in winemaking to improve both aroma formation and retention. In this study, we have analysed the oenological characteristics of Tempranillo wines produced at 12 and 28 degrees C by different Saccharomyces species and hybrids. Methods and Results. Low temperature had a strong influence on yeasts fermentation kinetics, increasing fermentation times to more than 2 weeks. In some strains, glycerol production seemed to be positively influenced by low fermentation temperature. Analysis of the aroma composition of wines produced by different Saccharomyces species and hybrids revealed large differences depending on fermentation temperature. Conclusions. Higher alcohols production seemed to be dependent on the strain. Production of acetate esters seemed to be favoured at 28 degrees C, whereas production of ethyl esters was apparently preferred at low fermentation temperatures. The best aroma producers at 28 degrees C were Saccharomyces cerevisiae strains, whereas Saccharomyces uvarum and some hybrids excelled at 12 degrees C. Significance and Impact of the Study. Our results suggest that fermentation temperature and yeast species are of crucial importance for production of metabolites influencing wine aroma