肌原纤维特性与鸡肉原料肉品质的关系

【目的】研究不同品种鸡胸肉肌原纤维特性与原料肉品质的关系，为筛选鸡肉加工专用品种、明确原料肉品质特性对鸡肉加工制品的影响提供理论依据。【方法】通过扫描电镜和透射电镜观察8个品种鸡胸肉的微观结构以及超微结构，利用Image-Pro Plus 6.0软件定量分析肌原纤维直径、密度以及肌节长度；同时结合原料肉蒸煮损失率、剪切力、质构特性以及肌原纤维小片化指数（MFI）等品质指标，借助相关分析，建立肌原纤维特性与原料肉品质之间的相关性。试验数据采用SAS9.2软件进行方差分析、多重比较分析和相关性分析。【结果】通过比较8个品种鸡胸肉的基本化学组成成分，发现不同品种鸡胸肉化学组成成分之间存在显著差异（P＜0.05），其中，乌鸡的水分含量为75.44%，显著高于（P＜0.05）其它品种，而柴母鸡的水分含量最低；蛋白质含量变幅较小，为22.03%—24.53%，三黄鸡的蛋白质含量最高，贵妃鸡的蛋白质含量最低；贵妃鸡的肌内脂肪含量为3.11%，显著高于（P＜0.05）其它品种。通过对8个品种鸡胸肉的基本品质指标分析，结果表明，不同品种鸡胸肉的色泽、pH、嫩度、持水能力及质构特性存在显著差异（P＜0.05）；矮脚鸡的亮度值和红度值显著高于（P＜0.05）其它几个品种；乌鸡胸肉的pH最高；贵妃鸡、清远鸡、乌鸡及童子鸡胸肉的剪切力较其它几个品种鸡小；乌鸡胸肉的蒸煮损失率最低。8个品种鸡胸肉的微观结构和超微结构观察结果显示，不同品种鸡胸肉的肌原纤维直径、密度、肌节长度及肌原纤维小片化指数之间也存在显著差异（P＜0.05），其中贵妃鸡、清远鸡、乌鸡及童子鸡的肌原纤维直径较细，密度较大；清远鸡的肌节长度最长；三黄鸡和贵妃鸡的MFI值较其它品种的大，分别为138.67和134.67。相关分析结果表明，肌原纤维直径与剪切力呈显著正相关（P＜0.05），肌原纤维密度与剪切力呈显著负相关（P＜0.05）；肌节长度与蒸煮损失存在显著负相关关系（P＜0.05）。【结论】肌原纤维特性与原料肉的品质存在密切的关联性，肌原纤维特性会对原料肉品质以及加工特性产生重要影响。

Study on Relationship Between Myofibril Characteristics and Meat Quality of Chicken Raw Meat

【Objective】The relationship between myofibril characteristics and meat quality of breast of different chicken varieties was investigated. The purpose of the present study was to provide a scientific basis for selection of special varieties and understanding of the effect of raw meat quality on the quality of meat products. 【Method】The microstructures and ultrastructures of breast muscle myofibril of eight Chinese native chickens were observed by scanning electron micrograph (SEM) and transmission electron microscope (TEM) , the quantitative analysis of myofibril characteristics was conducted by Image-Pro Plus 6.0, at the same time cooking loss, shear force, texture profile analysis (TPA) and myofibril fragmentation index (MFI) were measured. The correlation between myofibril characteristics and processing features was established by correlation analysis. The Statistic Analysis System 9.2 (SAS9.2) was used to analyze the variance, multiple comparison and correlation.【Result】Eight Chinese native chickens showed a significant difference in basic chemical compositions, colour, pH, tenderness, water holding capacity, texture properties, fibre diameter, fibre density, sarcomere length and MFI (P＜0.05). The water content of Silkie was significantly higher than the other varieties (P＜0.05) , and the Chai hens’ was the lowest. The protein contents of eight Chinese native chickens were ranging from 22.03% to 24.53%, and the extent of variation was minor. The protein content of Princess chicken was the lowest, but its fat content was the highest. The lightness and redness of Bantam were significantly higher than the other varieties (P＜0.05). The pH of Silkie was the highest. The shear forces of Princess chicken, Tsingyuan’s chicken, Silkie and Spring chicken were lower than the other varieties and the cooking loss of Silkie was the lowest. The fibre diameters of Princess chicken, Tsingyuan’s chicken, Silkie and Spring chicken were thinner, the fibre densities were denser; the sarcomere length of Tsingyuan’s chicken was the longest. MFI of Sanhuang chicken and Princess chicken were higher than the other varieties. The correlation analysis showed that the fibre diameter was positively correlated (P＜0.05) with shear force, but the fibre density was negatively correlated (P＜0.05) with shear force, the sarcomere length was negatively correlated (P＜0.05) with cooking loss.【Conclusion】There was a significant correlation between myofibril characteristics and meat quality, the myofibril characteristics had an important effect on meat quality.