考察了热处理温度对清远麻鸡腿肉蒸煮损失、质构、剪切力、微观结构及蛋白降解的影响。结果表明:清远麻鸡腿肉的蒸煮损失在55～85℃间显著增加;随着温度的升高,鸡腿肉的硬度不断增大,咀嚼性和弹性在低于75℃时显著增大,之后又持续减小;剪切力值在75～95℃间显著增加;加热对微观结构有破坏作用,在55～65℃时,肌膜发生热收缩,肌纤维直径减小,并出现"颗粒化";75～85℃时,肌纤维直径增大,肌纤维间隙显著减小,"颗粒化"现象逐渐减少;85～95℃时,肌纤维蛋白剧烈变性收缩,肌纤维间隙几乎消失,相邻肌纤维排列密实。全肌蛋白电泳表明分子质量66ku的原肌球蛋白以及55ku蛋白在75℃以上时降解消失,一个29ku的降解蛋白新条带在85～95℃被检出;渗出液电泳检出了高分子质量的可溶性胶原蛋白谱带。

Research was undertaken to investigate the effects of temperature on cooking loss,texture,shear force,microstructure and protein degradation of Qingyuan chicken thighs.The cooking loss increased significantly between 55~85℃.With temperature increasing,the hardness of chicken thighs increased continuously.When temperature was lower than 75℃,chewiness and springiness obviously increased with temperature increasing,while decreased when temperature was higher than 75℃.Heating treatment destroyed the microstructure of muscle.At 55-65℃,sarcolemma was shrink,muscle fiber diameter decreased and a phenomenon of granulation was observed.At 75~85℃,the muscle fiber diameter increased,gap between muscle fiber significantly reduced and "granular" phenomenon gradually reduced.While at 85~95℃,myofibrillar proteins was shrink severely because of denaturizing.Muscle fiber gap almost disappeared and adjacent muscle fiber arrangement became more compact and firmer.The SDS-PAGE patterns of whole muscle protein showed that the propomyosin with a molecular weight of 66 ku and protein with a molecular weight of 55KDa disappeared as a result of degradation when muscle was heated to above 75 ℃.While a new protein band with a molecular weight of 29 ku was detected at 85~95 ℃.A band of heat-soluble collagen with a higher molecular weight was detected in the exudates electrophoresis.