Protein degradation of olive flounder (Paralichthys olivaceus) muscle after postmortem superchilled and refrigerated storage

Figures & data

Figure 1. Changes in EC of olive flounder during chilled storage for 15 days. Data are the mean of triple replicates and vertical bars indicate ± SD.

Figure 2. Changes in shear force of olive flounder during chilled storage for 15 days. Data are the mean of triple replicates and vertical bars indicate ± SD.

Figure 3. Changes in TCA-soluble peptides of olive flounder during chilled storage for 15 days. Data are the mean of triple replicates and vertical bars indicate ± SD.

Table 1. Changes in FAA (mg/100g sample) content of olive flounder during chilled storage for 15 days.

		Samples stored at −2°C			Samples stored at 4°C
FAA	Taste attribute	0d	9d	15d	0d	9d	15d
Asp	Umami/sweet	0.52	1.19	3.34	0.52	7.89	13.97
Thr	Sweet	1.58	9.43	11.31	1.58	12.91	25.98
Ser	Sweet	3.14	9.75	4.55	3.14	12.9	14.74
Glu	Umami	1.52	16.69	24.92	1.52	29.56	78.41
Gly	Sweet/umami	1.08	5.02	10.9	1.08	8.98	30.97
Ala	Sweet/umami	7.39	4.48	43.91	7.39	38.35	90.12
Val	Bitter/sweet	2.7	29.05	14.7	2.7	12.61	49.51
Cys	Sweet/bitter/sulfurous	0.11	0.94	1.68	0.11	2.5	7.97
Met	Bitter/sweet/sulfurous	1.37	1.87	11.21	1.37	7.22	47.32
Ile	Bitter	2.09	3.16	12.26	2.09	9.67	48.09
Leu	Bitter	2.98	5.04	22.95	2.98	17.62	94.17
Tyr	Bitter	2.47	2.62	12.76	2.47	8.97	41.72
Phe	Bitter	1.93	2.75	13.92	1.93	9.04	62.56
Lys	Bitter/sweet	1.91	22.55	35.42	1.91	34.88	58.84
His	Bitter	1.21	1.89	5.5	1.21	4.28	13.49
Arg	Bitter/sweet	0.52	6.2	6.48	0.52	13.74	41.08
Pro	Bitter/sweet	1.48	4.65	8.96	1.48	7.97	10.81
Total FAA		33.99	127.28	244.76	33.99	239.09	729.75
NH3		0.02	0.06	0.1	0.02	0.07	0.29

Figure 4. Changes in proteolysis index of olive flounder during chilled storage for 15 days. Data are the mean of triple replicates and vertical bars indicate ± SD.

Figure 5. Changes in microstructure of olive flounder muscle during storage at −2°C (a) and 4°C (b) for 15 days. Arrows indicated gapping of muscle fibres.

Figure 6. SDS-PAGE pattern of olive flounder muscle proteins during chilled storage for 15 days (a: MFP samples at −2°C; b: SSP samples at −2°C; c: MFP samples at 4°C; d: SSP samples at 4°C).