Ethanol production by thermotolerant yeasts has been extensively studied,
because thermotolerant yeasts are capable of growth and fermentation during the
summer months in non-tropical countries as well as under tropical climates (Ueno et
al., 2001). Cooling costs during the process of ethanol production are expensive;
hence, by using thermotolerant yeasts cooling and distillation costs can be reduced
(Sree et al., 1999; Ueno et al., 2002). Considerable difficulties are associated with
fermentation in tropical areas owing to the lack of heat tolerance in conventional