Author(s): Neethu Ravikumar and Anooja Thomas K

Abstract:
Rice undergoes different post-harvest operations and among them, parboiling is very common method. Parboiling brings about a spectrum of qualitative changes in rice. Among three important steps of parboiling, soaking is the most crucial step as it changes the composition and distribution of nutrients within grains ^{[6, 7, 9]}. Soaking is a hydration process in which water diffuses into rice grains, essential for the complete gelatinization of starch. Soaking causes the leaching of rice constituents in the soaking water ^{[3, 7, 9]}. The present study was undertaken to do a comparative study on the proximate composition and morphological aspects of rice varieties and for comparison two varieties were selected namely “Jaya and Sulekha”. Both of them were subjected to cold soaking (12 hours), hot soaking (70 °C for 2 hours) followed by steaming and drying in sun. Amylose Content of the samples was determined spectrophotometrically and proximate composition by Pearson Composition Method. The morphological properties of the rice samples were studied using Scanning Electron Microscopy (SEM). Data collected were tabulated and consolidated. It was found the rice samples selected for the present study belongs to low amylose (Sulekha) and intermediate amylose (Jaya) varieties. The SEM micrographs of cold soaked samples were completely coagulated and hot soaked were partially distorted when a comparison is made with raw rice varieties. While looking onto the proximate composition it was observed that the both the carbohydrate and protein content decreased during parboiling, fat and moisture content showed a slight increase and ash content showed only a slight variations.