Optimizing parboiling conditions to improve grain quality and cooking properties of Agric and Ofada rice varieties

Rice is one of the most important food crops in Nigeria. This study evaluated the effect of parboiling temperature and time on some quality parameters in two varieties of rice grains (Agric and Ofada). The bulk density, rate of breakage, grain dimensions, and minimum cooking properties of the rice varieties were investigated using standard methods. The results showed that, during milling, when the optimum parboiling temperature of Agric and Ofada rice grains is not attained or is exceeded, the grains are prone to more breakage due to the milling efficiency of the machine. Minimal grain breakage was observed at 135°C for Agric rice and 150°C for Ofada rice when parboiled for 25 min. The grain size ranged from 6.3-6.9 mm for whole rice, 3.2-4.2 mm for half grains, and 0.7-1.8 mm for fragments. In conclusion, Agric rice parboiled at 135°C and Ofada rice parboiled at 150°C for 25 min exhibited optimal quality, including lower breakage rates, higher whole grain yield, and favourable sensory characteristics.