Abstract
Measurements were conducted for whole grain and outer layer components which are considered to contribute to taste of 31 types of rice. These results were added to the objective measurement method for eating quality of cooked rice according to the previous report, achieving even greater precision.
1. Examining the externality rate which expresses the externality rate of each component in the outer layers, water content was distributed evenly throughout the samples, but protein, Mg, K, total sugar, reducing sugars, free sugars, and free amino acids all have externality rates higher than 13%, making it clear that they predominate in the outer layers of the rice.
2. It was possible to express desirability of sweetness, which was seen to have a high correlation with the overall acceptability of cooked rice, in terms of three items, the total sugar in the whole grain, sucrose in the outer layers, and phenylalanine in the whole grain.
3. Overall acceptability of cooked rice could be expressed in terms of three items, sucrose in the outer layers, the L value, and the amylose ratio, with a multiple correlation coefficient of 0.85, substantially higher than multiple correlation coefficient of 0.68 from the objective measurement formula in the previous report 19) obtained from physical properties, and making it clear that better evaluation of the overall acceptability of cooked rice is possible.