Oenological Characterization of Traditional Starter Culture Used in the Production of Alcoholic Beverages

Abstract

Enology, a word comes from the Greek words for wine and study, is the term used to describe the science of winemaking.(Amerine et al.,1978).This science has its roots in pre-historic times, as the effects of alcohol were probably discovered when rotten fruit was consumed and found to have an intoxicating effect, which was considered as pleasant. Fermentation is a complex process, affected by various parameters ,which have an impact on the wine so formed. The factors influencing fermentation are- (Joshi et al.,1999) a. Carbon/energy sources: This means the supply of soluble sugars in the juice. Saccharomyces cerevisiae is capable of fermenting only a few simple sugars, and of those found in wine , only glucose and fructose are fermentable. The high sugar content may cause difficulty, initially due to osmalarity of the juice and later , due to the combined effects of ethanol and the osmolarity of the juice. b. Nitrogen content: Some fruits like grapes have ample ammonium or amino nitrogen to complete the fermentation whereas other fruits require the addition of ammonium salts which indirectly affects the aromatic character of wine. c. Lipids: They play an important role in yeasts, including nutrient storage and regulation. However, relative to fermentation their main significance involves cell membrane function. d. Alcohol content: The increasing content of alcohol eventually inhibits yeast metabolism even in the presence of fermentable sugars. Ethanol disrupts the transport of sugars across the cell membrane. e. Temperature: It can influence fermentation by affecting the rate of enzyme action.