Abstract
The quality, appearance, cooked quality and palatability of koshihikari rice cultivated at the Agricultural Experimental Station of Nagano prefecture were investigated during six phases, from before maturation to after maturation, in different harvest seasons. The grain thickness distribution showed that the 5% green ratio grains tended to be 2.0 mm and more thicker than the 0% green ratio grains. The respective appearance, showed significantly more complete grains and significantly fewer cracked grains. The respective gelatinization characteristic value, showed significantly higher breakdown, and significantly lower, final viscosity and setback with the 5% green grains. The palatability of both the 5% green ratio and 0% green ratio grains was superior to that of rice in any other harvest season. Samples from the six phases were assigned three groups from these results, and both the 5% green ratio and 0% green ratio grains were classified as positive for the first principal component and second principal component. A factor analysis evaluated, the negative factor related to “hardness” in the palatability evaluation, and the positive factor related to “comprehensive evaluation” and “taste”. The overall results show that, rice harvested with a 5% green ratio was superior in grain thickness distribution, appearance and gelatinization characteristics to the 0% green ratio grains.
