Improving head rice rate with water cooling process

In order to reduce the formation and growth of cracks within milled rice kernel caused by air cooling before the further polishing process, a new technical process was explored. The influences of temperature of cooling water and cooling time on the final temperature of rice, and the effects of water cooling method on the head rice rate of polished rice were investigated on a self-design test-bed for the water-cooling rice. And the complex heat transfer coefficient of rice with water cooling method was determined. The head rice rate of rice after the polishing process was abtained with water and air cooling method respectively. Excel and SAS software were used to analyze the experimental data. The results showed that, the temperature of cooling water and cooling time had significant effects on the final temperature of rice; the complex heat transfer coefficient of rice of 181.13 kJ/(m2·℃·h) was determined; the head rice rate with water cooling was 4 to 9 percentage higher than that with air cooling method when the moisture content of the brown rice was 15%-16%. The results can provide a theoretical basis for water cooling method of rice and design of water cooling equipment.