高湿度结合不同温度解冻对猪肉理化及蛋白特性的影响

探究相对湿度（relative humidity，RH）90%下，不同温度（0、4、8?℃和12?℃）解冻对猪肉品质特性的影响，以鲜肉和传统低温（4?℃，RH?65%～73%）解冻肉为对照，分析处理组和对照组的解冻效率、保水性、嫩度、色泽、脂质过氧化、pH值、新鲜度的变化，并利用差示扫描量热仪和流变仪测定蛋白热变性及动态流变特性。结果表明：相较于传统低温解冻，高湿（RH?90%）、低温（0～12?℃）解冻可提高解冻效率，且解冻后猪肉的保水性、色泽、嫩度显著提高（P＜0.05），明显抑制脂肪氧化程度，降低蛋白变性程度，可最大限度维持“鲜肉”的品质；其中，高湿环境下4?℃和8?℃解冻效果明显优于0、12?℃处理组，解冻后猪肉的保水性、色泽、嫩度得到改善，脂肪氧化程度降低，同时4?℃和8?℃解冻后猪肉蛋白变性程度较低，G′较高。因此RH?90%、4～8?℃解冻是较合适的解冻条件，该条件可提高解冻效率、维持猪肉品质。

Effect of High-Humidity Thawing under Different Temperatures on Physicochemical Characteristics and Protein Properties of Frozen Pork

This study was conducted to analyze the effect of different thawing temperatures (0, 4, 8 and 12 ℃) under high relative humidity (RH 90%) on the quality characteristics of frozen pork. Fresh pork and conventional low temperature thawing (4 ℃, RH 65%–73%) were considered as control. Thawing rate as well as physicochemical characteristics including water-holding capacity (WHC), tenderness, color, lipid oxidation (2-thiobarbituric acid reactive substances (TBARS) content), pH and freshness were measured and compared among various groups. Protein thermal denaturation and rheological properties were examined as well by a differential scanning calorimeter (DSC) and a rheometer, respectively. The results showed that compared with the conventional low temperature thawing, high-humidity low-temperature thawing could improve the thawing efficiency. The WHC, color and tenderness were improved and lipid oxidation was inhibited significantly (P < 0.05). Also, protein denaturation was reduced. As a result, high-humidity low-temperature thawing provided the best maintenance of fresh pork quality, and thawing at 4 and 8 ℃ was significantly better than at 0 and 12 ℃ as evidenced by improved WHC, color and tenderness, reduced lipid oxidation, lower degree of protein denaturation, and higher storage modulus G’. Therefore, thawing at 90% humidity and 4–8 ℃ could enhance the thawing efficiency, and maintain pork quality and could be more suitable for frozen pork.