Dynamics of yeast during the primary fermentation phase

8 Dynamics of yeast during the primary fermentation phase 

Most fermentation of grape juice is conducted by non-growing cells. Current understanding of metabolically active but non-proliferative states in yeast is limited. In the 

Grape juice also contains a wide array of phenolic compounds such as benzoic and cinnamic acids, flavanols, and anthocyanidins, the composition and levels of which vary dramatically with the grape variety, from trace amounts to mg/L concentrations (Amerine et al., 1980). Many of these compounds have been shown to be bioactive in 

2 Microbial dynamics during fermentation impact of yeast strain diversity 

Not surprisingly, the fimess of strains for specific fermentation niches also has been found to vary. In some cases, only one or a few strains dominate throughout fermentation (Versavaud et al., 1995). In contrast, other researchers have found that different strains dominate at different stages of the fermentation (Sabate et al., 1998), or that several strains of Saccharomyces appear to be simultaneously present in equivalently high numbers (Torija et al., 2(X)1 Vezinhet et al., 1992). Presumably, the biodiversity 

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