The Korean rice, Nonglim # 6 was milled into brown rice and 92% polished one and packed with the kraft paper bags. The sample, bags were irradiated with the respective doses of 30, 50, 600 and 800 Krad and then were stored at 10℃ and 75% RH. Changes of fat acidity, amylase activity, viscosity of thus irradiated rice were examined during storage. The results were as follows.
1) Fat acidity increased slightly in the range of 30∼50 Krad but remarkably in the range of 600∼800 Krad. However, the rate of increase was low in comparison with the storage under the room temperature.
2) The amylase activity of both the low dose lot and the control decreased in the same rate during the storage. However the high dose lot had more remarkable decrease of the amylase activity from the beginning.
3) The viscosity by Brabender amylogram showed the slightly decreasing tendency in both the low 30∼50 Krad lot and the control lot of the polished rice powder during storage. On the other hand, the high dose lot of 600 or 800 Krad marked the similar decreasing rate but by far the lower values of the viscosity.
4) The results of the organoleptic test presented no differences between the low dose lot and the control lot, but the high dose lot and the control lot differed significantly only in the color.
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