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In this study the effects of grain moisture content, variety and whitening time on whiteness index, as well as the percentage of breakage were examined. The varieties used were Alikazmi, Binam and Khazar with three moisture content levels of 12.5-14%, 11-12.5% and 9.5-11% on a wet basis. Whitening times were 15, 30, 45 and 60 seconds. The results showed that the whitening times had no significant effect on breakage percentage, but increase in whitening time from 15 to 60 sec. caused an increase in whiteness index. There were significant differences observed among the varieties. Aliazemi and Khazar sustained a maximum and minimum rice breakage, respectively. Whiteness index of Khazar variety was significantly higher than that in the other two varieties. Rice breakage was a minimum in the range of 9.5-11% moisture content for all the three varieties