Table 4 Amino nitrogen contents and protease activities of cheonggukjang fermented with millimeter wave irradiation

Sample	Amino-type nitrogen contents (mg %)	Protease activity (U/g)
Control	597.33±21.391)^b2)	0.075±0.016^b
60 GHz	527.33±32.33^c	0.069±0.006^c
70 GHz	779.33±16.17^a	0.093±0.011^a

Mean±S.D
^a-cMeans with different superscripts in each column indicate significant differences (p< 0.05).