Brokens for Head Rice Yield Determination

Milled rice from a laboratory mill and a commercial–scale mill was evaluated for head rice yield using a shaker table and a machine–vision system called the GrainCheck. Comparisons were made for both medium– and long–grain rice varieties. For each variety, samples with different levels of broken kernels were analyzed to determine the performance of the two instruments over a range of head rice yields. Percentage head rice was also measured by the FGIS for commercially milled samples to compare the shaker table and the GrainCheck with an official measurement. Head rice yield values were found significantly different between the two instruments for all of the laboratory–milled samples but the mean head rice yield variation was equivalent for both instruments. Commercially milled rice showed that the FGIS and GrainCheck percentage whole kernel measurements were equivalent while the shaker table average was seven percentage points less. Similar trends were found for both varieties.