REMOVING METHOD OF PRECURSOR FOR DIMETHYL SULFIDE FROM RICE

PURPOSE:To remove a precursor for dimethyl sulfide with a high efficiency, by reacting a proteolytic enzyme and an acid with rice in dipping the rice in water. CONSTITUTION:In dipping rice in water, a proteolytic enzyme and an acid are added and reacted with the rice to remove a precursor for dimethyl sulfide from the rice. The method provides a particularly high removal ratio of the precursor amounting to >=90% when the dipping temperature is 40-60 deg.C. The optimal dipping temperature or rice has been 10-15 deg.C in the past, and the dipping at a relatively high temperature of >=20 deg.C causes the contamination of the rice with bacteria. The resultant contaminated rice is known to color to reddish brown by cooking with steam. According to the method, the contamination by the bacteria will not occur even by dipping the rice at a relatively high temperature >=20 deg.C, and the loss of starch by flowing out is scarcely caused. The treated rice can be cooked with steam by the conventional method to give the aimed snow white cooked rice.