PROBLEM TO BE SOLVED: To provide a method for producing natto utilizing the characteristics of charcoal and capable of producing more delicious and more satisfactory natto.SOLUTION: Provided is a method for producing natto utilizing the characteristics of charcoal continuously performing: the first step where raw material beans are immersed in water and are smothered thereafter, next, Bacillus natto is inoculated thereto so as to be subdivided by prescribed quantity, and they are stored in a fermentation chamber in which Bincho charcoal is arranged at the inner wall face the second step where fermentation with the Bacillus natto is performed at a room temperature of 40 to 60°C for 1 to 2 hours in the fermentation chamber the third step where the temperature in the fermentation chamber is increased and the concentration of oxygen in the fermentation chamber is reduced by burning charcoal from oak (Quercus), thus the concentration of carbon dioxide and the concentration of carbon monoxide are increased to suppress the fermentation by the Bacillus natto the fourth step where the fermentation chamber is opened and air is taken therein, thus the concentration of the oxygen in the fermentation chamber is rapidly increased and the temperature in the fermentation chamber is controlled to 40 to 45°C to rapidly activate the suppressed fermentation by the Bacillus natto and the fifth step where, after the progression of the fermentation, the temperature is reduced to finish the fermentation.SELECTED DRAWING: None
