This study was conducted to investigate the effects of different tempering methods and freeze-thaw cycles on melanosis and quality parameters of pacific white shrimp. Frozen pacific white shrimps tempered with radio frequency tempering (RFT) were compared to that in water tempering (WT) and refrigerator tempering (RT) in terms of temper loss, total volatile base nitrogen (TVBN), polyphenol oxidase (PPO) activity, melanosis, total sulfhydryl contents, differential scanning calorimetry (DSC), and texture properties after 0, 1, 3, 5 freeze-thaw cycles. Results showed that crushed ice was effective as an effective surrounding medium for six layers of frozen shrimp reaching −2 °C within 6 min in RFT. For quality attributes, the temper loss of samples tempered with radio frequency is lower than that of RT and WT after all freeze-thaw cycles, and RFT resulted in the lowest TVBN value (9.17 mgN/100 g) of shrimps after the 5th freeze-thaw cycle. The PPO activity and melanosis of samples increased as the number of freeze-thaw cycles increased, and RFT effectively inhibited the development of melanosis. After the 3rd freeze-thaw cycle, the enthalpy change (△H) and the sulfhydryl content (0.16 mmol/gprot) of radio frequency tempered samples was significantly higher (p < 0.05) than that of WT and RT. RFT retained the hardness and chewiness of shrimp samples in all freeze-thaw cycles. Therefore, RFT effectively inhibited melanosis and reduce protein oxidation in Pacific white shrimp during freeze-thaw cycles with its fast and uniform heating characteristics.

本研究旨在研究不同回火方法和冻融循环对太平洋白虾黑变病和质量参数的影响。将用射频回火 (RFT) 回火的冷冻太平洋白虾与水回火 (WT) 和冰箱回火 (RT) 在回火损失、总挥发性基氮 (TVBN)、多酚氧化酶 (PPO) 活性、黑变病方面进行比较、总巯基含量、差示扫描量热法 (DSC) 和 0、1、3、5 次冻融循环后的质地特性。结果表明，碎冰可作为有效的周围介质，使六层冷冻虾在 RFT 中在 6 分钟内达到 -2°C。对于质量属性，在所有冻融循环后，射频回火样品的回火损失低于 RT 和 WT，在第 5 次冻融循环后，RFT 导致虾的最低 TVBN 值（9.17 mgN/100 g）。样品的PPO活性和黑变病随着冻融循环次数的增加而增加，RFT有效抑制了黑变病的发展。第 3 次冻融循环后，焓变 (△H ) 和射频回火样品的巯基含量 (0.16 mmol/gprot) 显着高于 WT 和 RT ( p < 0.05)。RFT 在所有冻融循环中都保留了虾样品的硬度和咀嚼性。因此，RFT以其快速均匀的加热特性有效抑制了太平洋白虾在冻融循环过程中的黑变病并减少了蛋白质氧化。