Production of an Alcoholic Beverage from Rice (Oryzae sativa) Using Nigerian Palm Wine Yeasts

Abstract

Rice wine is an alcoholic beverage of cereal produced as a result of fermentation of rice by selected yeasts isolated from different substrates. In this study the effects of starter cultures on physico-chemical and sensory properties of rice wine were investigated. The yeasts isolated belong to six genera and these are Saccharomyces, Kluveromyces, Schizosaccharomyces, Candida, Rhodotorula and Geotrichum. The species isolated included S. cerevisiae, S. uvarum, S. chevallieri, Klu. africanus, Schizosaccharomyces japanicus, S. pombe, C. castelli, C. intermedia, R. graminis and G. candidium. The wort produced from rice had fermentable sugars and nitrogen sources for yeast metabolism and alcoholic fermentation. The wort fermented with Saccharomyces cerevisiae had the highest ethanol concentration of 3.90% compared to 2.16% and 3.7% recorded for Klu. africanus and S. uvarum respectively. The taste results are appearance (2.6-3.8), taste (2.1-3.6), flavor (2.3-3.7), aroma (2.6-3.4) and overall acceptability (2.4-3.6).  The rice wine produced with S. cerevisiae also received the highest scores in all the parameters evaluated by the taste panelist. Therefore, it could be concluded that rice wine of acceptable quality could be produced by using S. cerevisiae isolated from palm wine.