ABSTRACT
Yeasts are strongly inclined to perform alcoholic fermentation under both aerobic and anaerobic conditions. Yeast is non-motile, non-photosynthetic and, like all fungi, may reproduce sexually and/or asexually. Perfect fungi undergo both reproductive cycles, while imperfect fungi only reproduce asexually. Sexual reproduction in yeast takes place via conjugation of few haploid cells of different mating types and subsequent sporulation by meiosis, introducing genetic variation to a population, although this type of reproduction is very rare in some yeast species. Under optimal conditions, yeast cells demonstrate a typical microbial growth curve. Temperature is a crucial parameter in wine fermentation, since it affects the yeast growth, the development of alcoholic fermentation and therefore, the sensory quality of the final product. In fact, the must and the fermentation temperature, condition the number of different species and their survival during alcoholic fermentation, affecting the chemical and sensory qualities of the wine.
