EFFECT OF STORING TIME AND TEMPERATURE ON MILLING QUALITY OF PAR BOILED AND RAW RICE OF AN IMPROVED IVARIETY, AT 362 AND A TRADITIONAL VARIETY, KURULUTHUDA

Abstract

Future rises in global surface temperature threaten for rice dependent nations. Previous research has failed to account for the detrimental impact of high temperatures on milling quality in paddy storing. Therefore, main ob jectives of this study were to assess the milling quality of paddy stored at different temperatures in line with global warming and to identify adaptation techniques. Experiment was conducted as a split-split plot design with 3 repli cates. Main, sub and sub-sub plot factors were variety (AT-362, Kuruluthuda), processing technique (raw, par boiled) and storage temperature (26, 30, 34, 38oC) respectively. Head Rice Yield (HRY), Broken Rice Yield (BRY) and Degree of Milling (DOM) were estimated initially and after 6 months. Result revealed that HRY of paddy decreased by the range of 2.1-3.5% with increase in storage temperature from 26°C to 38°C after 6 months. How ever, temperature was not significantly influenced on HRY and BRY of stored paddy (P>0.05). The DOM was significantly lower (2.07%) at 38oC than other temperatures. The HRY is significantly higher (P<0.05) in par boiled rice than raw rice in both varieties after 6 month at each temperature level. It can be concluded that mill ing quality of stored paddy is degrading at high temperatures yielding high amount of broken rice and low head rice, Furthermore, Kuruluthuda variety stored at comparatively high temperatures seems to be more tolerant to breakage during the milling compared with AT-362.