Effect of Soaking Temperature on Physical, Chemical and Cooking Properties of Parboiled Fragrant Rice

KDML 105 is the most popular fragrant rice for export and consumption in Thailand but it has poor milling yield. To solve this problem, parboiling has been used for improving milling quality of damaged rice. Our present study investigated the effect of soaking temperature on physical, chemical and cooking properties of parboiled rice. The 12-month stored KDML 105 paddy samples were soaked at 40, 50 and 60°C for 3 h, then autoclaved with steam at 121°C 15 min and dried by cabinet tray dryer at 60°C to reach the moisture content of 23 g/100 g dry matter. Head milling yield was significantly increased from 51% in brown rice to 60-80% in parboiled rice. The results also showed that parboiling process significantly (p<0.05) increased protein, lipid and ash contents. Overall, soaking at 50°C for 3 h prior to steaming and drying was found to provide the most desirable quality of parboiled rice in our study in terms of nutritional quality and sensory properties.