Table 2.
Effects of treatments and storage time on colour changes in pork chops.
| Item | Treatment | Storage Time (Days) | |||||
|---|---|---|---|---|---|---|---|
| 0 | 5 | 10 | 15 | 20 | 25 | ||
| L *1 | T0 | 52.50 ± 1.93 b | 59.02 ± 1.22 a | 58.48 ± 1.72 a | 61.08 ± 1.28 a | 61.03 ± 1.09 a | 60.40 ± 1.36 a |
| T1 | 52.31 ± 2.68 b | 52.57 ± 2.16 b | 54.12 ± 1.64 b | 55.54 ± 1.25 b | 58.50 ± 1.48 a | 58.76 ± 1.98 a | |
| T2 | 53.47 ± 2.16 b | 54.34 ± 2.31 b | 54.27 ± 1.99 b | 55.80 ± 1.51 b | 55.24 ± 1.38 b | 56.04 ± 1.40 b | |
| T3 | 54.33 ± 1.85 b | 55.79 ± 2.17 b | 55.91 ± 0.78 b | 56.33 ± 1.54 b | 54.50 ± 1.63 b | 54.84 ± 1.17 b | |
| a *1 | T0 | 2.56 ± 0.43 a | 2.05 ± 0.38 a | 1.55 ± 0.33 b | 1.20 ± 0.29 c | 1.22 ± 0.32 c | 1.19 ± 0.02 c |
| T1 | 1.76 ± 0.60 b | 1.60 ± 0.57 b | 1.54 ± 0.43 b | 1.25 ± 0.24 c | 1.26 ± 0.18 c | 1.14 ± 0.49 c | |
| T2 | 1.78 ± 0.52 b | 1.71 ± 0.36 b | 1.65 ± 0.18 b | 1.61 ± 0.32 b | 1.60 ± 0.18 b | 1.61 ± 0.10 b | |
| T3 | 1.78 ± 0.36 b | 1.70 ± 0.24 b | 1.72 ± 0.07 b | 1.62 ± 0.22 b | 1.60 ± 0.12 b | 1.59 ± 0.11 b | |
| b *1 | T0 | 11.83 ± 0.58 c | 12.78 ± 0.19 b,c | 12.07 ± 0.63 b,c | 12.69 ± 0.21 b,c | 13.30 ± 0.75 a,b | 13.84 ± 0.35 a |
| T1 | 10.44 ± 1.01 c | 10.10 ± 1.25 c | 10.94 ± 1.02 c | 11.36 ± 0.78 c | 13.13 ± 0.90 a,b | 13.22 ± 0.22 a | |
| T2 | 10.49 ± 1.21 c | 11.22 ± 0.95 c | 11.35 ± 1.05 c | 11.50 ± 1.04 c | 11.46 ± 0.80 c | 11.18 ± 0.79 c | |
| T3 | 10.51 ± 1.57 c | 11.73 ± 0.89 c | 11.03 ± 1.34 c | 11.12 ± 1.32 c | 11.84 ± 0.83 c | 11.85 ± 0.65 c | |
| L *2 | T0 | 38.60 ± 1.37 d | 38.96 ± 0.79 d | 43.73 ± 1.39 c | 54.37 ± 1.77 a | 53.61 ± 1.42 a | 52.34 ± 1.55 a |
| T1 | 45.80 ± 1.94 c | 43.17 ± 2.25 c | 43.69 ± 1.23 c | 51.24 ± 0.94 b | 54.45 ± 1.19 a | 54.27 ± 1.87 a | |
| T2 | 43.82 ± 1.35 c | 45.04 ± 1.71 c | 46.47 ± 2.89 b,c | 51.88 ± 1.03 b | 49.33 ± 1.22 b | 48.13 ± 0.66 b | |
| T3 | 43.74 ± 2.32 c | 43.70 ± 0.70 c | 48.83 ± 0.82 b,c | 50.67 ± 1.27 b | 50.04 ± 1.75 b | 49.65 ± 1.52 b | |
| a *2 | T0 | 20.17 ± 1.70 a | 22.82 ± 1.49 a | 18.21 ± 0.03 b | 6.14 ± 1.37 e | 6.94 ± 1.16 e,f | 5.08 ± 0.46 f |
| T1 | 13.64 ± 0.82 c | 12.56 ± 0.87 c | 8.76 ± 0.66 e | 6.44 ± 0.71 e | 6.39 ± 0.55 e | 5.05 ± 0.83 e,f | |
| T2 | 12.30 ± 0.54 c | 11.43 ± 1.73 c,d | 11.83 ± 0.37 d | 8.23 ± 1.82 e | 7.51 ± 0.47 e | 6.20 ± 0.52 e | |
| T3 | 14.52 ± 0.98 c | 13.80 ± 1.51 c | 10.88 ± 1.62 d | 7.92 ± 0.31 e | 7.37 ± 0.53 e | 6.76 ± 0.53 e | |
| b *2 | T0 | 17.71 ± 1.84 a | 17.44 ± 1.55 a | 17.19 ± 0.70 a | 12.73 ± 0.54 b | 10.74 ± 1.52 c | 10.35 ± 1.28 c |
| T1 | 17.59 ± 1.56 a | 16.11 ± 1.33 a | 12.15 ± 0.70 b | 9.71 ± 0.72 c | 9.91 ± 0.78 c | 9.69 ± 0.87 c | |
| T2 | 14.29 ± 1.58 a,b | 14.26 ± 1.82 a,b | 11.09 ± 1.00 b,c | 10.91 ± 1.69 c | 10.69 ± 0.58 c | 10.82 ± 0.30 c | |
| T3 | 14.43 ± 1.41 a,b | 12.31 ± 1.19 b | 11.52 ± 0.95 b,c | 10.72 ± 1.87 c | 10.79 ± 0.33 c | 10.42 ± 1.21 c | |
Values expressed as mean ± standard deviation. *1, colour of meat surface; *2, colour of bone surface; T0, non-coated chops without antioxidant; T1, chitosan without GTWE; T2, chitosan with 0.1% of GTWE; T3, chitosan with 0.5% of GTWE; Different superscripts (a–f) indicate significant differences among treatment x storage time effects (p < 0.05).