Abstract:
The understanding of the quality traits of early Indica rice produced in Hubei and Jiangxi provinces of 2015 will provide reference data for the quality index of cooked rice and quality improvement.This study was conducted to determine appearance quality (grain type,chalkiness and chalky kernel percentage),the physical and chemical characteristics (amylose,crude protein and crude fat content) and pasting characteristics and cooking quality of 82 early Indica rice samples produced in Jiangxi and Hubei provinces.The results showed that the variation coefficient of 17 quality indexes was greater than 10% in the 21 indexes tested,which implied that the samples collected in this study were of different quality levels and had good representativeness.The proportions of chalkiness,chalky kernel percentage and amylose contentreaching to the third-grade of national standard of paddy were 17.1%,26.8%,63.4% and 43.9%,respectively.Correlation analysis found that the grain shape,chalky kernel percentage,chalkiness,amylose content,the blue value of iodine,trough value and breakdown value were the important indexes to affect the comprehensive palatability of early Indica rice.The results of principal components analysisshowed that the cumulative variance contribution rate of the first 3 principal components was 71.5%,which included the quality characteristics of most rice samples.The contribution rates of the first,second and third principal component were 50.8%,13.2% and 7.5%,respectively.The samples were divided into two types according to the first principal component,which were Hubei and Jiangxi provinces two categories.The early Indica rice produced in Hubei province had the characteristics of high chalkiness rate,high chalkiness,high amylose content and low breakdown value,while the early Indica rice in Jiangxi province had the opposite trend of the above characteristics.