Low-protein rice for chronic kidney disease patients and individuals requiring reduced protein diet

Dietary protein restriction is used as a therapeutic measure for early onset of chronic kidney disease (CKD) to retard progressive deterioration in renal function that will require dialysis. A dietary intake of 0.6 to 0.8g protein/kg/day is usually recommended. In our country where rice is the staple food, reducing its protein content would be an excellent strategy to help CKD patients and other individuals who require a low-protein diet. This study was conducted to evaluate the suitability of Philippine rice varieties in the preparation of low-protein rice. Five varieties with varying sizes, shapes, and amylase content (AC) were used: Japonica-type NSIC Rc304 (low-AC) and NSIC Rc242 (low-AC), and Indica-type NSIC Rc160 (low-AC), NSIC Rc222 (intermediate-AC), and NSIC Rc152 (high-AC). The preparation followed the process established by Biotech Japan Corporation, a leading manufacturer of low-protein rice. The samples were then evaluated for content, sensory attributes, Instron hardness, and color (L and b values). The process was found to be effective in reducing the protein to 0.25-1.55%. The samples had comparable aroma and taste with no off-taste. In terms of texture, the Japonica-type varieties were too cohesive and tender with low Instron hardness values: 0.68 kg/cm sup 2 (NSIC Rc304) and 1.04 kg/cm2 (NSIC Rc242). The intermediate-AC NSIC Rc222 and high-AC NSIC Rc 152 had higher tendency to become hard and separated at room temperature. Both Japonica-type varieties had unpleasant yellowish color which was also manifested in their lower L and higher b values. With its considerable good sensory attributes and cooked rice texture, the Indica-type, low-AC NSIC Rc160 was the most acceptable. This study shows that local rice varieties with appropriate quality characteristics can be used in the development of low-protein rice which can be consumed by Filipinos requiring reduced protein diet.