Grain quality evaluation of japonica rice effected by cultivars, environment, and their interactions based on appearance and processing characteristics

Abstract

Appearance and processing characteristics of 45 japonica rice samples, collected from different regions in Jiangsu province, were investigated and evaluated in this study. Specifically, the chalkiness degree had been presented significant differences among different cultivars and regions. The average chalkiness degree varied from 6.81% to 15.34% for different regions and from 1.93% to 28.31% for different cultivars. The minimum head rice rate of cultivars from four regions, NJ9108 (HA), was 80.5%. The AC of CNG10, HD5, and PJ surpassed 13.68% and lower than 11.33% for the others. The protein content ranged from 6.1% to 11%, and the taste value was significantly different among cultivars. In addition, the RVA curves of the samples were similar, but the peak viscosities of NG8 and NJ5055 were higher than others, and there were significant differences in RVA traits among regions. Cultivars were the main reasons for the difference in appearance and processing quality of japonica rice, while environmental factors had leaded to the change of rice composition, texture, and gelatinization.

Effects of biochar on rice yield, grain quality and starch viscosity attributes

“…Starch viscosity was measured using a rapid viscosity analyzer (RVA‐3, Newport Scientific, Warriewood, NSW, Australia) and analyzed using companion software Thermal Cycle Windows (TWCs). The specific operation steps are described by Xia et al 18 . RVA spectrum eigenvalues included peak viscosity, hot paste viscosity, cool paste viscosity, breakdown viscosity obtained from the peak viscosity minus hot paste viscosity, setback viscosity obtained from cool paste viscosity minus hot peak viscosity, consistency viscosity obtained from cool viscosity minus hot paste viscosity, peak time and pasting temperature.…”

“…Rice grains were equilibrated for 3 months after harvest, and empty grains were removed. The brown rice, milled rice and head-milled rice rates were measured as described by Xia et al 18 Grain chalkiness, chalky rice rate and length-width ratio were determined using an appearance quality scanner (MICROTEK, ScanMaker i800 plus). The amylose content was determined according to the method of Zeng et al 19 Gel consistency was determined according to the method of Huang et al 20…”