PREPARATION OF KOJI

PURPOSE:To produce KOJI (malt of rice, soybean, etc.) for SAKE, MISO, etc., with saved labor, without boiling or steaming the raw material, by mixing seed malt to the raw material composed of carbohydrates and vegetable proteins, feeding the mixture to an extruder controlled to a specific temperature and extruding the mixture through an extrusion die to effect the expansion of the extrudate. CONSTITUTION:A seed malt is mixed to a carbohydrate raw material and/or vegetable protein raw material (preferably rice, barley or soybean), and supplied to an extruder having a barrel temperature of 80-150 deg.C, preferably 80-120 deg.C. The mixture is extruded through the extrusion die to effect the expansion, and preferably the expanded product is imposed to the KOJI-preparation condition to obtain the objective KOJI. The water-content of the mixture of the above raw material and seed malt is preferably adjusted to 13-35%.