On the contrary, moisture content decreased with the fermentation time. It changed from 35-40% to 19-22% during 72 h of fermentation in 3 different combinations of substrates (Fig. 1b). The sample contained higher content of soybean showed higher initial moisture content. The decreasing of moisture content was caused by the mycelia growth of A. oryzae S. during fermentation. Moreover, moistening brings a suitable aw for mold growth because of the easy penetration of mycelia into the substrates [9]. It was opposite to the results of Chutmanop et al. [5] that the moisture content of fermented wheat and rice bran increased during fermentation. It might be due to the different substrates. Soybean particle is bigger than rice and wheat bran. It supports air circulation and affect oxygen and heat transfer in the substrate.