摘要
取屠宰后5头杂交牛（鲁西黄牛X西门塔尔）的背最长肌，置于2—4℃贮藏7d，注射样品重10％的血管紧张素Ⅱ，观察在成熟过程中血管紧张素Ⅱ对牛肉剪切力、肌原纤维小片化指数（MFI）、凋亡酶活力，以及肌纤维直径变化的影响。结果显示：贮藏期间对照组和处理组样品剪切力均显著下降（P〈0．05），MFI值逐渐增大，caspase-3、6、9酶活力宰后迅速激活随后其活力逐渐下降；血管紧张素Ⅱ注射处理显著降低了牛肉的剪切力值和肌纤维直径（P〈0．05），而对MFI值及caspase-3、6,9活力无显著影响。因此，caspase-3、6,9对牛肉嫩度的影响可能仅发生在宰后初期极短的一段时间内；肌细胞宰后生理和活体状况下不太一致，血管紧张素Ⅱ注射降低了牛肉剪切力可能由于它能显著防止肌纤维的收缩。
Five crossbred cattles （Luxi × Simmental） were slaughtered and LD samples obtained from carcasses were aged for 7 days, meanwhile the influences of the injection of Angiotensin Ⅱ solution （10% of weight） on beef shear force, myofibrillar fragmentation index （MFI）, activity of caspase-3,6,9 and diameter of myofibers were observed. Results showed that during storage, the shear force decreased significantly （P 〈0.05） as well as the MFI increased gradually both in the control group and in the injection groups, while caspase -3,6,9 were activated and their activity fell off gradually. The injection of Angiotensin Ⅱ could lead to the significant decline of shear force and diameter of myofibers in skeletal muscle postmortem（P 〈0.05）, while it had no significant influence on the MFI and activity of caspase-3,6,9. Therefore, the effects of caspase-3,6,9 on beef quality might take place only in the very short period after slaughter. The decrease of shear fore by Angiotensin Ⅱ was possibly due to its obvious inhibition to the contraction of the myofibers.
出处
《江西农业学报》
CAS
2009年第11期114-117,共4页
Acta Agriculturae Jiangxi
基金
江苏省高等学校大学生实践创新训练计划项目(JSS0801)
