The rice qualities including cooking and eating qualities were studied using recommended Korean rice varieties (20 of japonica and 3 of indica type; IR 667) which were grown at Suwon, Korea in 1971. As the result, followings were obtained.
1. Amylose contents of white rice were varied with the varieties 21.1 to 25.5% and the average was 23.0%.
Three indica type varieties (IR 667) showed higher amylose contents than the other japonica type varieties except Mankyung.
Among japonica type varieties, Palkum, Mankyung composed the group of the highest amyloes content and Kimmaje was the lowest.
2. Blue values were distributed in the range of 0.38 to 0.48 and the average was 0.42.
IR 667 varieties showed the highest blue value among them.
Among japonica type varieties, Jaegun showed the highest blue value and Sooseung, Shirogane showed successively lower values, Shin #2, Nongbaik, Palkweng, Suwon #82, Mankyung, Nonglim #25 and Nongkwang relatively lower blue values.
3. Alkali numbers were in the range of 6.0 to 7.4 and the average was 6.8. Much difference was not shown in alkali number between IR 667 group and the japonica varieties group.
4. Gelatinization temperature were ranged from 59.5 to 64.0
IR 667 varieties showed relatively higher gelatinization temperature than japonica type varieties.
5. Water uptake ratios were measured in the range of 2.67 to 2.92 and the average was 2.79.
IR 667 varieties were belonged to the group of highest water uptake ratio.
Among japonica type varieties Kimmaje, Suwon #82, Nonglim #29, Deungpan #5, Jaegun, Jinhung, were belonged to the group of relatively high water uptake ratio and Palkweng, Palkeum and Paldal to the relatively low water uptake ratio.
6. Expaned volums were ranged from 29.8 to 33.7 and the average was 31.8.
IR 667 varieties showed higher expanded volumes than japonica type varieties.
7. Intensities of starch-iodine blue value of residual liquid indicated 0.35 to 0.58. Among them IR 667 varieties showed relatively high intensities.
8. The range of total solids in residual liquids was 0.605 to 0.810 and the average was 0.700
Much difference was not shown in total solids in residual liquid between IR 667 varieties and japonica varieties.
9. pH values of residual liquids were in the range of 6.3 to 7.3 and the average was 6.95.
IR 667 varieties showed lower pH than japonica type varieties.
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