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

摘要:

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pH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。

Abstract:

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 pH, 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.