Characterization of Lactic Acid Bacteria and Yeast Isolates Associated With Traditional Soaking of “Ofada” Rice

Abstract

Freshly harvested paddy rice was randomly obtained from three different farms in "Ofada" town, Ogun State, Nigeria into sterile polythene bags and processed according to the traditional method. The acidity and microbial counts of the soakwater of the rice were determined at 24-h intervals for 72 h. Lactic acid bacteria and yeast were also isolated from the soak-water and characterized and identified by standard schemes. The total titratable acidity, aerobic plate, lactic acid and yeast counts of the soak-water increased significantly (P < 0.05); the pH and coliform counts decreased significantly within 48 h, while coliform organisms were eliminated by the 72-h mark. The dominant lactic acid bacteria found to be responsible for the fermentation of "ofada" rice were Leuconostoc mesenteroides and Lactobacillus amylophillus, while the dominant yeasts were Saccharomyces cerevisiae and Saccharomyces uvarum. These isolates could be responsible for the relished flavor of "ofada" rice. PRACTICAL APPLICATIONSThis work reports on the isolation of lactic acid bacteria and yeasts responsible for imparting peculiar flavor on "Ofada" rice during traditional soaking. Furthermore, the isolated microorganisms can be used as starter cultures to improve the quality of the rice and also shorten the soaking time.