Abstract

Gas liquid chromatography was used to identify the types of alcohol present in wines produced by fermenting orange juice with four strains of yeast; Saccharomyces cerevisiae (isolated from yam), S. cerevisiae (from sugarcane molasses),Saccharomyces carlsbergensis (from sugarcane molasses) and S. cerevisiae var. ellipsoideus (from orange juice). Ethanol and methanol were the predominant alcohols. The ethanol content was highest, 90.38% with S. cerevisiae var. ellipsoideus and least, 81.49% with S. cerevisiae (from sugarcane molasses). The methanol concentration varied between 9.51% with S. cerevisiae var. ellipsoideus and 14.93% with S. carlsbergensis. The other alcohol detected, isopro-panol was generally negligible; 0.10 to 0.25% except with S. cerevisiae (from sugarcane molasses) which produced it as 5.46% of the total alcohol. The total alcohol was highest, 6.50 ± 0.15% with S. carlsbergensis and least 3.23 ± 0.12 with S. cerevesiae var. ellipsoideus.

Key words: Alcohol types, fermentation, orange wine, Saccharomyces, yeast strains.