Effect of multi-step soaking process on head rice yield of parboiled paddy

ABSTRACT- Parboiling is one of the postharvest hydrothermal treatments applied on rough rice before drying and milling processes. This process has an important role in retaining the quality of rice kernels during storage, milling, and cooking. In this study, two rough rice cultivars, Tarom and Fuji Minory, were subjected to conventional and multi-step soaking for 90 minutes in water at temperatures of 50, 60 and 70 °C as a part of the parboiling process. Multi-step soaking was conducted in two and three steps followed by 15 minutes steaming at atmospheric pressure. Drying was performed by a fixed bed hot air dryer at 35 °C. The results indicated that in the conventional soaking, soaking temperature and steaming time affected the percentage of broken rice, bending strength and head rice yield (HRY) for both cultivars in a significant manner (P<0.05). The effect of soaking steps and steaming duration on the percentage of broken rice, bending strength, and HRY at temperature 70 °C were significant (P<0.05) for both rice cultivars. In overall, the multi-step soaking showed a significant positive impact on measured traits as compared to conventional soaking.