Quality Characteristics of Gochujang Meju Prepared with Different Fermentation Tools and Inoculation Time of Aspergillus oryzae

To standardize a preparation method for traditional gochujang, 4 types of meju were prepared using different fermentation tools and inoculation time of Aspergillus oryzae with Bacillus subtilis. The acidic protease activities of the S-1 and S-2 were higher and significantly different than those of S-3 and S-4 on 8-day fermentation at 30 C. The free amino acid contents of the meju were high, in the order of S-2 (275.9 mg%, w/w) > S-1 (238.3 mg%) > S-3 (215.0 mg%) > S-4 (189.9 mg%). The amino-type nitrogen contents of the S-1 (355.6 +/- 12.3 unit/mL) and S-2 (327.0 +/- 5.8 unit/mL) were higher and significantly different than those of S-3 and S-4 on 4-day fermentation. However, no consistent differences were observed between S-1 and S-2 during the fermentation period. Therefore, we conclude that meju fermentation was largely affected by the inoculation time of A. oryzae rather than the fermentation tool (tray or net).