Brunton N P, Lyng J G, Zhang L, Jacquier J C
Department of Food Science, Faculty of Agriculture, University College Dublin, Belfield, Dublin 4, Ireland.
Meat Sci. 2006 Feb;72(2):236-44. doi: 10.1016/j.meatsci.2005.07.007. Epub 2005 Aug 26.
Dielectric properties of beef biceps femoris muscle were recorded during heating (5-85°C) to assess their linkage to phase changes monitored by differential scanning calorimetry (DSC) and rheology. DSC indicated endotherms between 56 and 81°C corresponding to denaturation of actin, collagen and myosin. Matching changes in dielectric properties (dielectric constant (ε') and loss factor (ε″)) were noted at radio and/or microwave frequencies though the nature of the change differed depending upon frequency. The main observation in ε' was an increase above 65-66°C, most likely due to fluid release on collagen denaturation. This fluid plus liquid from myosin denaturation most likely solvated ions freed during myosin denaturation which manifested as an ε″ increase. However, it must be noted that meat structural protein denaturation is compounded with physical shrinkage which can also influence dielectric properties. Rheological parameters of beef muscle heated from 5 to 85°C also displayed marked changes relating to structural protein denaturation.
在加热（5 - 85°C）过程中记录了牛肉股二头肌的介电特性，以评估其与通过差示扫描量热法（DSC）和流变学监测的相变之间的联系。DSC表明在56至81°C之间存在吸热峰，对应于肌动蛋白、胶原蛋白和肌球蛋白的变性。尽管变化的性质因频率而异，但在射频和/或微波频率下观察到了介电特性（介电常数(ε')和损耗因子(ε″)）的匹配变化。ε'的主要观察结果是在65 - 66°C以上增加，这很可能是由于胶原蛋白变性时释放的液体所致。这种液体加上肌球蛋白变性产生的液体很可能使肌球蛋白变性过程中释放的离子溶剂化，这表现为ε″增加。然而，必须注意的是，肉类结构蛋白变性与物理收缩同时存在，这也会影响介电特性。从5加热到85°C的牛肉肌肉的流变学参数也显示出与结构蛋白变性相关的显著变化。
