Table 4. Changes in free amino acid contents (mg%, w/v) of brown rice vinegar during fermentation periods

Free amino acid	Fermentation time (day)
Free amino acid	0	4	8	12	16
Leu	1.97±0.01¹⁾^c2)	1.82±0.01^b	1.81±0.04^b	1.77±0.02^ab	1.70±0.06^a
Ile	0.70±0.00^b	0.65±0.00^ab	0.67±0.03^ab	0.66±0.04^ab	0.62±0.02^a
Met	0.43±0.01^b	0.40±0.01^a	0.38±0.01^a	0.37±0.00^a	0.38±0.02^a
Thr	0.57±0.05^a	0.65±0.00^a	0.63±0.05^a	0.66±0.01^a	0.65±0.03^a
Phe	1.35±0.00^b	1.29±0.00^a	1.27±0.00^a	1.25±0.01^a	1.24±0.04^a
Lys	1.52±0.01^a	1.50±0.02^a	1.50±0.01^a	1.48±0.01^a	1.48±0.04^a
His	0.44±0.00^a	0.46±0.01^a	0.46±0.01^a	0.46±0.01^a	0.46±0.01^a
Gly	0.66±0.00^a	0.66±0.01^a	0.66±0.01^a	0.65±0.01^a	0.63±0.01^a
Ser	0.78±0.06^b	0.75±0.01^ab	0.69±0.06^ab	0.7±0.01^ab	0.68±0.01^a
Glu	2.11±0.04^d	1.64±0.01^c	1.51±0.01^b	1.47±0.04^ab	1.43±0.04^a
Pro	1.30±0.01^e	1.11±0.02^d	1.00±0.04^c	0.82±0.06^b	0.72±0.05^a
Tyr	1.07±0.00^a	1.06±0.00^ab	1.06±0.00^ab	1.03±0.00^a	1.03±0.01^a
Ala	1.31±0.02^a	1.58±0.05^b	1.57±0.01^b	1.55±0.02^b	1.52±0.05^b
Asn	0.53±0.01^a	ND³⁾	ND	ND	ND
Asp	0.72±0.03^a	ND	ND	ND	ND
Arg	0.17±0.01^ab	0.18±0.01^b	0.17±0.01^ab	0.17±0.01^ab	0.16±0.01^a
GABA	1.00±0.01^e	0.85±0.02^d	0.77±0.01^c	0.67±0.04^b	0.47±0.04^a
Total amino acid	21.84±0.34^c	20.07±0.19^b	19.62±0.18^ab	19.24±0.08^ab	18.79±0.59^a

Values are mean±SD (n=2).
Different lower-case letters (^a-e) in the same row indicate a significant difference according to Duncan's multiple test (p<0.05).
ND is an abbreviation for not detected.