Effects of Parboiling on Improving the Proximate Compositions of “Selam” Green Super Rice, Grown in Ethiopia

In addition to treducing the broken rice due to the increase in hardness of the kernel through gelatinization, the parboiling process enhances the concentration of nutrients in rice grain. The husk and bran contain various nutrients, and during the soaking and steaming processes, soluble materials from these layers dissolve and migrate into the grain's endosperm, enriching its nutritional content. In this study, the Super Green 'Selam' rice variety was used with three factors evaluated having three levels. Soaking temperatures of 40°C, 60°C, and 80°C; soaking durations of 6, 12, and 24 hours; and steaming times of 15, 25, and 35 minutes were used, with non-parboiled rice acted as as the control group. For this study, a completely factorial design with a CRD configuration was applied. The parboiling process significantly improved the proximate components of the rice (P < 0.05). After 12 hours of soaking at 80°C followed by 35 minutes of steaming, the starch content increased to 60.53%. Crude protein, fat, and ash levels ranged from 5.25% to 6.62%, 1.56% to 2.67%, and 0.74% to 1.28%, respectively. Additionally, the combinations of pre-heat treatment, soaking, and steaming treatments led to crude fiber levels of 1.04% to 1.48% and carbohydrate content ranging from 74.97% to 78.47%. The trend generally showed that increasing the factors levels also improved the proximate components proportionally.