Comparative studies on physicochemical properties of rice with germinated dark purple giant embryo rice and normal embryo rice

Abstract

AbstractBackground and objectivesAs a cultivar developed by breeding, pigmented rice Keunnunjami has a dark purple pericarp and a giant embryo and has been found to possess strong antioxidant properties. The present study investigated the effect of 72‐hr germination on the physicochemical properties of Keunnunjami, in comparison with that of its parental pigmented normal embryo cultivar, Heukjinju, and ordinary normal brown rice.FindingsGermination generally increased the amounts of reducing sugar, amino acids isoleucine, leucine, phenylalanine, valine, alanine, cysteine, glycine, proline, and tyrosine, and minerals such as calcium, magnesium, and phosphorus while it decreased the levels of histidine, lysine, methionine, threonine, arginine, aspartic acid, glutamic acid, serine, and potassium in the rice grains. The germinated Keunnujami exhibited higher amounts of essential and non‐essential amino acids and reducing sugar than the germinated Heukjinju and normal brown rice. The starch granules from all rice samples showed holes and pits on the surface after germination.ConclusionsThese changes in the chemical composition and morphological properties are possibly due to partial hydrolysis of starch and protein caused by enzymes that were activated during germination.Significance and noveltyResults of this study could serve as the baseline information for evaluating the quality and possible food industry applications of germinated Keunnunjami.