Table 2. Color of dark muscles and white muscles of mackerel fillets stored under different conditions

Type of muscle	Item	Storage method	Storage period (days)				SEM¹⁾
Type of muscle	Item	Storage method	0	1	3	6	SEM¹⁾
Dark muscle	CIE L*	A	44.91	40.62	44.41	42.36	1.637
		I	44.91	41.37	45.30	42.55	0.826
		R	44.91	41.70	41.46	41.62	1.504
		FTW	44.91^a	37.68^b	39.44^b	39.80^b	1.583
		FTR	44.91	43.70	41.13	43.84	1.248
		SEM²⁾	-	1.486	1.737	1.386
	CIE a*	A	11.88	14.42^xy	12.84^xy	15.61^x	0.928
		I	11.88	16.36^x	15.01^x	16.51^x	0.639
		R	11.88	14.79^bxy	16.06^ax	16.99^ax	0.436
		FTW	11.88	13.41^y	11.24^y	10.70^y	0.826
		FTR	11.88^b	13.53^ay	12.90^axy	10.99^by	0.215
		SEM²⁾	-	0.510	0.986	0.402
	CIE b*	A	15.25^c	17.82^ab	17.42^b	19.47^a	0.408
		I	15.25^b	17.65^ab	18.44^a	18.59^a	0.382
		R	15.25^b	17.26^ab	17.02^ab	18.52^a	0.304
		FTW	15.25^b	18.10^a	17.01^ab	17.75^ab	0.991
		FTR	15.25^ab	18.41^a	18.32^a	18.42^a	0.428
		SEM²⁾	-	0.627	0.649	0.634
	H	A	52.65	51.62	55.41	51.25^y	1.931
		I	52.65	47.22	50.92	48.74^y	1.655
		R	52.65	48.82	47.00	47.43^y	0.832
		FTW	52.65	53.41	56.69	58.85^x	1.798
		FTR	52.65^b	53.48^b	54.82^b	59.16^ax	0.690
		SEM²⁾	-	1.283	2.205	1.523
White muscle	CIE L*	A	52.45	56.55	53.17	55.35	1.518
		I	52.45	60.81	51.69	60.11	2.301
		R	52.45^b	59.39^a	50.91^b	59.83^a	1.355
		FTW	52.45	58.31	51.11	53.61	2.050
		FTR	52.45^b	61.33^a	55.23^ab	54.16^b	1.363
		SEM²⁾	-	2.467	1.077	1.423
	CIE a*	A	2.91	2.16	4.18^xy	1.70^y	0.524
		I	2.91^ab	1.63^b	5.47^ax	2.56^aby	0.751
		R	2.91^ab	1.23^b	5.77^ax	1.99^by	0.417
		FTW	2.91^ab	0.87^b	4.44^axy	1.90 ^aby	1.130
		FTR	2.91^ab	1.27^b	2.73^aby	5.61^ax	0.724
		SEM²⁾	-	0.428	0.537	0.604
	CIE b*	A	15.34	16.17^yz	15.65^yz	16.29^xy	0.279
		I	15.34^ab	15.42^abyz	16.43^axyz	14.60^by	0.354
		R	15.34	14.50^z	15.01^z	15.14^xy	0.451
		FTW	15.34	16.98^xy	16.68^xy	15.88^xy	0.493
		FTR	15.34^b	18.13^ax	17.42^ax	17.31^ax	0.393
		SEM²⁾	-	0.395	0.322	0.506
	H	A	79.14	83.45	77.85^xy	83.99^x	1.542
		I	79.14	84.42	71.86^yz	80.05^xy	2.596
		R	79.14^ab	85.15^a	69.44^bz	82.65^axy	1.687
		FTW	79.14	86.74	75.27^xyz	83.11^x	3.944
		FTR	79.14^ab	86.00^a	81.57^abx	72.19^bz	2.172
		SEM²⁾	-	1.488	1.716	2.155

Dark muscle, brown or reddish tissue on the flesh; white muscle, white to off-white tissue on the flesh.
n=3 of standard error of the least square mean.
n=15 of standard error of the least square mean.
Different superscripts indicate significant difference among means (p<0.05).
Different superscripts indicate significant difference among means (p<0.05).
A, ambient; I, ice; R, refrigerator; FTW, frozen and thawed in water; FTR, frozen and thawed in a refrigerator; H, hue angle.