Department of the Science of Food of Animal Origin, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
Meat Sci. 1995;41(1):7-17. doi: 10.1016/0309-1740(94)00066-G.
Tenderisation of bovine Mm. longissimus dorsi and triceps brachii and factors impacting tenderisation were studied. Mm. longissimus dorsi and triceps brachii of 12 Friesian-Holstein cows (age 3-11 years; 212-349 kg carcass weight) were sampled at various times post mortem (p.m.) for determination of pH, temperature, fibre type and morphology, connective tissue distribution, SDS-PAGE of myofibrillar proteins, Warner-Bratzler shear force, sarcomere length and osmolality. The stretched position of the M. triceps brachii (sarcomere length 2.35 ± 0.24 μm) resulted in a relatively low shear force at 1 day p.m. (6.2 ± 0.9 kg/cm(2)) with further storage having little additional effect. M. longissimus dorsi entered rigor in a more contracted state (sarcomere length 1.65 ± 0.11 μm), resulting in a relatively high shear force at 1 day p.m. (10.3 ± 2.3). Stepwise linear regression was used to calculate the best 1- to 3-variable equations for shear force of M. longissimus dorsi at 1, 7 and 14 days p.m. and the decrease in shear force between 7 and 14 days p.m. Shear force at 1 day p.m. appeared to be determined mainly by the speed of pH- and temperature-decline. Proteolysis of myofibrillar proteins and animal age appeared to be the main determinants for shear force at 1 and 14 days p.m. The average surface area of type I fibres could explain part of the variation in the decrease in shear force between 1 and 14 days p.m.
研究了牛的腰最长肌和肱三头肌的嫩化以及影响嫩化的因素。在死后不同时间（p.m.）从 12 头弗里斯兰荷斯坦奶牛（年龄 3-11 岁；212-349kg 胴体重量）中取样，用于测定 pH 值、温度、纤维类型和形态、结缔组织分布、肌原纤维蛋白的 SDS-PAGE、华纳-布拉泽尔剪切力、肌节长度和渗透压。肱三头肌的拉伸位置（肌节长度 2.35±0.24μm）导致 1 天 p.m.时剪切力相对较低（6.2±0.9kg/cm(2)），进一步储存几乎没有额外影响。腰最长肌以更收缩的状态进入僵硬状态（肌节长度 1.65±0.11μm），导致 1 天 p.m.时剪切力相对较高（10.3±2.3）。逐步线性回归用于计算 1、7 和 14 天 p.m.时腰最长肌剪切力以及 7-14 天 p.m.期间剪切力下降的最佳 1-3 变量方程。1 天 p.m.时的剪切力似乎主要由 pH 值和温度下降的速度决定。肌原纤维蛋白的蛋白水解和动物年龄似乎是 1 天和 14 天 p.m.时剪切力的主要决定因素。I 型纤维的平均表面积可以解释 1 天和 14 天 p.m.之间剪切力下降的部分变化。
