Comparative Assessment of Grain Quality Characteristics and Cooking Parameters of White Rice (Oryza sativa Indica and Oryza sativa Japonica) Varieties Cultivated in Sri Lanka

Traditional rice varieties (Oryza sativa L.) from Sri Lanka are less popular due to limited consumer awareness. Demand is influenced by grain quality, cooking properties, sensory attributes, and nutritional value. This study compared traditional white rice varieties with improved ones and examined the Nipponbare Japonica variety. Milling quality varied significantly (p < 0.05) across traditional varieties, except for bran percentage. Head rice percentages ranged from 61.05 to 74.28%, and broken rice percentages ranged from 1.98 to 43.04%. Nipponbare had 48.77% of head rice and 20.78% of broken rice. Rice sizes ranged from short to long, and shapes varied from round to medium. All selected varieties had a hard gel consistency and high amylose content, except Nipponbare. Cooking parameters like elongation ratio, cooked length-to-breadth ratio, water uptake, volume expansion ratio, and cooking time showed significant differences (p < 0.05). Rathal, Suduru Samba, Suwendel, and Kahawunu are comparable to improved varieties in milling and cooking quality. The milling quality of Nipponbare is similar to improved varieties, but its cooking characteristics are intermediate compared to traditional and improved varieties.