Effects of Rewetting on Milling Quality of Wet Season Japanese Rice

Abstract

Study on rewetting of wet season Japanese rice after harvest was conducted at Faculty of Agriculture, Chiang Mai University. The rewetting process was simulated by spraying water at different amounts on the paddy which was mechanically dried to the pre-determine moisture contents of 15-21%. The paddy was sprayed with water until its moisture increased 3% and 6%. The grain was kept for 12 hours before redried to 12-13% moisture level and milled. Results of the experiment showed that rewetting of 3% gave no milling quality difference from the unwetted crop both in terms of % head rice and% broken rice. But when the paddy was wetted until its moisture increment was 6% a significantly different head rice yield and broken rice percentage from the control were observed. Moreover, it was found that the paddy moisture content and the amount of water rewetted had interacted effects on milling quality of the Japanese rice. Nonetheless the rewetting effect of 3 and 6% on the rice in wet season not serious since the broken rice yield did not exceed 10% which was commercially acceptable.