Ripening   0 5 10 15 20 Aspartic acid 1527.35 ± 44.99b1) 1534.48 ± 36.71b 1752.82 ± 33.76a 1781.01 ± 50.90a 1802.22 ± 41.13a Threonine2) 740.21 ± 16.44d 783.60 ± 15.63c 852.09 ± 18.14b 834.53 ± 26.29b 888.54 ± 17.49a Serine 724.18 ± 16.39c 769.84 ± 16.51b 791.23 ± 10.04b 793.12 ± 18.09b 831.63 ± 19.03a Glutamic acid 2329.09 ± 58.42b 2330.84 ± 73.62b 2558.86 ± 61.10a 2564.70 ± 58.43a 2456.46 ± 65.36a Proline 620.39 ± 17.23c 714.29 ± 14.37b 741.68 ± 21.18b 814.61 ± 18.38a 793.08 ± 17.29a Glycine 624.45 ± 13.01c 551.28 ± 13.63d 693.65 ± 18.41b 686.05 ± 20.55b 781.34 ± 18.51a Alanine 881.80 ± 23.40c 944.16 ± 26.17b 964.70 ± 21.32b 971.95 ± 19.83b 1121.70 ± 25.75a Cystine 442.49 ± 9.81d 572.17 ± 12.98b 633.86 ± 15.86a 643.50 ± 16.09a 479.49 ± 11.11c Valine2) 614.94 ± 12.91e 659.55 ± 15.73d 756.12 ± 23.82b 719.27 ± 16.38c 833.40 ± 20.06a Methionine2) 468.07 ± 14.88c 573.19 ± 13.27b 574.75 ± 13.18b 588.87 ± 12.74b 658.12 ± 16.49a Isoleucine2) 536.29 ± 11.26d 632.76 ± 15.12c 666.18 ± 20.12b 654.92 ± 15.56bc 745.56 ± 17.53a Leucine2) 1143.01 ± 28.11c 1385.55 ± 27.20b 1364.98 ± 35.10b 1385.89 ± 32.10b 1451.89 ± 27.64a Tyrosine 428.94 ± 9.79c 546.49 ± 14.60b 545.34 ± 11.27b 543.82 ± 12.83b 587.60 ± 6.48a Phenylalanine2) 485.92 ± 9.57c 571.08 ± 13.03b 586.59 ± 16.41b 580.41 ± 15.28b 641.28 ± 6.61a Histidine2) 495.43 ± 11.33d 542.02 ± 15.42c 563.04 ± 13.75bc 565.72 ± 7.39b 589.03 ± 12.56a Lysine2) 1642.29 ± 43.70c 1914.07 ± 42.24b 1929.84 ± 61.10b 1941.10 ± 58.08b 2046.92 ± 46.96a Arginine 836.61 ± 18.24c 969.63 ± 22.74b 982.25 ± 21.06b 992.97 ± 22.26ab 1028.61 ± 28.58a Total 14541.46 ± 344.49c 15995.01 ± 486.39b 16957.98 ± 383.33a 17062.46 ± 372.28a 17736.87 ± 516.11a

1) Values are means ± SD (n = 3). Values with different superscripts in the same row are significantly different at P<0.05 by Duncan's multiple range test.2) Essential amino acid

Table 5: Total amino acid contents of skate during different ripening periods (mg/100 g).