We developed a novel method to measure cooked rice whiteness using a scanner and new software for image analysis. Cooked rice, filling a plastic dish (35 mm in diameter), was subjected to the measurement using a scanner, and the b* value, which indicates yellowness, was calculated by the software. The value of b* was negatively and significantly correlated with whiteness in sensory tests of cooked rice. The value of b* also showed significant varietal differences. These results show that cooked rice whiteness could be estimated by b* value. The value of b* was negatively and significantly correlated with the appearance and overall evaluation in sensory tests of cooked rice. Therefore, cooked rice whiteness is one of the most important attributes in sensory tests of eating quality. In addition, b* value was negatively and significantly correlated with heading date. Because this method needs only a small amount of polished rice, it is expected to be used to select promising lines having high eating quality at an early generation during breeding.

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