Relationships Between Cooking Properties and Physicochemical Properties in Brown and White Rice

Brown rice presently attracts a growing number of customers due to its perceived health benefits, but its cooking properties differ from white rice. This study aims to investigate the relationship between physicochemical properties and cooking properties of brown rice and white rice. Brown rice samples generally are found to have higher thousand kernel weight, and minimum cooking time, but lower length/breadth ratio, pasting viscosity values (except setback), swelling power, water uptake ratio, gruel solid loss, cooked length/breadth ratio, and elongation ratio than white rice. Brown and white rice from the same cultivar show some differences regarding their gelatinization properties. The cooking property differences between brown and white rice may be explained by impact of embryo and protection by bran layers. Correlation analysis indicate that cooking properties are little correlated to the flour physicochemical properties, except minimum cooking time. Although apparent amylose content show strong correlations with most flour physicochemical properties, gelatinization temperature may be preferred to be used for prediction of minimum cooking time in both brown and white rice.