Freshly harvested paddy rice was randomly obtained from three different farms in "Ofada" town, Ogun State, Nigeria and processed according to the traditional parboiling method. The rice was inoculated singly with cultures of Lactobacillus amylophilus, Leuconostoc mesenteroides, Saccharomyces uvarum and Saccharomyces cerevisiae which were isolated from the soak-water. In order to assess the effect of starter cultures on the soaking time of the rice, the pH and titratable acidity were determined at 12 h interval. The chemical composition and the sensory quality of the rice were also determined at the end of the soaking period while uninoculated rice served as control. The chemical composition of the rice as well as the pH and TTA of the soak-water were significantly (p < 0.05) different from the control while the processing time was shortened to 48 h. The rice inoculated with Saccharomyces uvarum and Saccharomyces cerevisae had the highest protein content and best sensory attributes.

No 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.