Department of Animal Sciences, Quality of Food of Animal Origin, Georg-August-University Goettingen, D-37075, Goettingen, Germany.
Poult Sci. 2011 Aug;90(8):1774-81. doi: 10.3382/ps.2010-01073.
Broilers from the lines Ross 308, Ross 708, and Cobb 700 were slaughtered at 28 and 41 d of age at a commercial abattoir. After slaughter, the carcass, breast, and leg weights as well as the breast and leg yields were determined. Further investigations analyzed the color [lightness (L*), redness (a*), and yellowness (b*)], pH at 24 h postmortem, electrical conductivity (EC), drip loss, grill loss, and shear force values as well as the muscle fiber cross-sectional areas of the breast muscles. The 41-d-old broilers had higher carcass, breast, and leg weights than the 28-d-old birds. The breast yield values were higher and the leg yields were lower in the 41-d-old broilers. The fiber cross-sectional area values were also higher in the older birds. Within the younger birds the slaughter characteristics were approximately comparable among the lines. The EC, L*, grill loss, and shear force values increased but the drip loss and a* values decreased with the age of the broiler. The genetic lines differed within the 28-d-old broilers with regard to EC, grill loss, and shear force values and within the 41-d-old broilers with regard to the EC, L*, grill loss, and shear force values. The pH correlated negatively with the EC, L*, b*, drip loss, and shear force values. During storage, L* and b* values of the breast muscles increased and a* values decreased in all genetic lines, whereas the L* values were generally higher in the older broilers and the a* and b* results were generally higher in the breast muscles of the younger broilers. In conclusion, the carcass and meat quality characteristics of broilers changed with age with positive (carcass and breast muscle weight, drip loss) but also negative (L*, a*, grill loss) effects. The effect of the genetic line was rather low. Despite the age-related changes of meat quality parameter, the pH values remained unchanged, indicating muscle structural influences on the muscle-to-meat-transition with increasing age of the broiler.
罗斯 308、罗斯 708 和科布 700 品系的肉鸡分别在 28 日龄和 41 日龄在商业屠宰场进行屠宰。屠宰后，测定屠体、胸肌和腿重以及胸肌和腿的出肉率。进一步的研究分析了胸肌的颜色（亮度（L*）、红度（a*）和黄度（b*））、宰后 24 h 的 pH 值、电导率（EC）、滴水损失、烤损失、剪切力值以及肌肉纤维横截面积。41 日龄的肉鸡屠体、胸肌和腿重均高于 28 日龄的肉鸡。41 日龄的肉鸡胸肌出肉率较高，腿肉出肉率较低。较老的鸡的纤维横截面积值也较高。在较年轻的鸡中，不同品系的屠宰特征大致相似。随着肉鸡年龄的增长，EC、L*、烤损失和剪切力值增加，而滴水损失和 a值降低。在 28 日龄的肉鸡中，不同品系的 EC、烤损失和剪切力值存在差异，在 41 日龄的肉鸡中，不同品系的 EC、L、烤损失和剪切力值存在差异。pH 值与 EC、L*、b*、滴水损失和剪切力值呈负相关。在所有遗传品系中，胸肌的 L和 b值在贮藏过程中增加，a值降低，而在较老的肉鸡中 L值通常较高，在较年轻的肉鸡中 a和 b值通常较高。总之，随着年龄的增长，肉鸡的屠体和肉质特性发生了变化，具有积极的（屠体和胸肌重量、滴水损失）和消极的（L*、a*、烤损失）影响。遗传品系的影响相当低。尽管肉质参数随年龄变化，但 pH 值保持不变，这表明随着肉鸡年龄的增长，肌肉结构对肌肉向肉的转变有影响。
