姜汁提取物对鸭肉嫩化及肌原纤维微观组织结构的影响

Effects of Ginger Extract on Tenderness and Myofibrillar Ultrastructure of Duck Breast Muscle

本研究探讨了姜汁提取物对鸭肉的嫩化、肌肉全蛋白SDS-PAGE电泳以及微观组织结构的影响。利用姜汁提取物对鸭肉在4±1℃条件下腌制48 h。对照组和姜汁处理组(5%,姜汁:鸭肉=mL:g)分别在不同时间(0 h、6 h、12 h、24 h、36 h和48 h)取样分析。结果表明:整个腌制过程,色差未受影响(p>0.05);24 h腌制时间内,姜汁处理组的p H值、持水力和MFI(肌原纤维小片化指数)分别由5.92、26.00%和76.38增高到5.98、35.04%和97.45(p<0.05);肌原纤维蛋白含量和剪切力值分别由108.01 mg/mL、32.71 N下降到83.78 mg/mL和23.75 N(p<0.05);24 h以上未有显著改变(p>0.05)。SDS-PAGE电泳显示,24 h后肌球蛋白和肌动蛋白发生了明显的降解。透射电镜观察,腌制24 h的鸭肉肌节明显变短,Z线断裂溶解,出现了肌原纤维小片化现象。相对于对照组,5%的生姜提取物在4±1℃下对鸭肉进行腌制处理24 h,即可显著降解肌原纤维,提高鸭肉的嫩度,改善鸭肉的品质。

The changes in the tenderness and myofibrillar ultrastructure of duck breast muscles upon marination in ginger extract（GE） were evaluated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis（SDS-PAGE）. Duck breast muscles were marinated for 48 h in GE at 4±1 ℃. Samples from the control group and the GE-marinated group（5% GE：duck breast muscle = mL：g） were collected after 0, 6, 12, 24, 36, and 48 h of marination. Little difference was found in color between the control and GE-marinated samples after 48 h. However, between 0 and 24 h of marination, the p H, water-holding capacity, and the myofibrillar fragmentation index（MFI） of the GE-marinated samples increased from 5.92, 26.00%, and 76.38 to 5.98, 35.04%, and 97.45（p〈0.05）, respectively. In contrast, myofibrillar protein solubility and shear force value decreased from 108.01 mg/mL and 32.71 N to 83.78 mg/mL and 23.75 N（p〈0.05）, respectively, in the same amount of time. No significant changes were observed in any of the parameters after 24 h（p〉0.05）. The SDS-PAGE results indicated that myosin and actin bands in the GE-marinated samples degraded rapidly after 24 h. Transmission electron microscopy（TEM） also revealed shortening of sarcomeres and breakdown and dissolution of Z-discs, in addition to the occurrence of myofibrillar fragmentation. Compared to the control samples, samples marinated for 24 h in 5% GE at 4±1 ℃ could significantly degrade myofibrils and enhance the tenderness of duck breast muscles, thereby improving its quality.