Biochemistry & Analytical Biochemistry

Abstract

Physicochemical Characterization of Selected Rice (Oryza Sativa L.) Genotypes Based on Gel Consistency and Alkali Digestion

Lagat Rose Chemutai, Mawia A Musyoki, Wambua F Kioko, Njagi S Mwenda, Karau G Muriira and Ngugi M Piero

Quality assessment of rice genotypes involves physicochemical and sensory test. A physicochemical test relies on the rice chemical composition, cooking quality, gelatinization temperature and physical properties of cooked rice. The aim of this study was to determine the physicochemical characteristics of selected Kenyan and Tanzanian genotypes based on gel consistency and alkali digestion. Diverse classes of rice exist with different expression levels of gel consistency and alkali digestion. As these traits are major contributors to the eating and cooking quality traits, unscrupulous traders mix both low and high-grade rice hence making enormous profits from their sales. Minitab 17.0 software package was used to determine the means and the standard error of means of the gel consistency physicochemical test results while the alkali digestion values were determined based on the standard evaluation system by International Rice Research Institute. Majority of the genotypes had high alkali digestion. Based on the gel consistency test, the average GC values ranged from 31.50 mm in ITA 310 to 99.5 mm in IR 2793. Genotype BS 217 showed significant difference from Kilombero, IR 64, Kahogo, Saro 5, ITA 310, IR 54, Wahiwahi and BW 196. These results show that physicochemical characterization using the available test procedures can be effectively utilized in analysis of diversity in rice germplasm.