Abstract
It is very difficult to discriminate black-wedged and pecky rice grains from healthy unhulled ones. Detection of these infested grains is generally made in hulled rices. However, this method is time-consuming and laborious. In the present experiment, the author attempted to develop a simple and rapid discriminating method of these infested grains and found that when unhulled rice grains were soaked in water for 20∼24 hours, both of the black-wedged and pecky grains could be easily distinguished in a semitransparent white plastic container placed on a light. The results of discrimination were dependent on the water temperature; a high temperature more than 30°C gave a poor result, but constant or varying temperatures in the range from 5° to 25°C gave a satisfactory one. Accelerated water absorption of rice grains in a vacuum chamber may provide a prompt detection of infested grains when required.
