Morphological changes in cooked longissimus dorsi muscle of pig, buffalo, sheep, goat and poultry

In an effort to establish the morphological differences between the cooked muscles of pig, buffalo, sheep, goat and poultry longissimus dorsi were examined. Cooking at 100 degrees C produced shrinkage of muscle fibres in all species. The demarcation of the fascicles was also lost. Cooking at 121 degrees C destroyed even the granulated structure of collagen, reducing it to an amorphous state. The transverse striations were lost and the muscle fibres showed cracking, breaking and splitting. In relation to the control the per cent values of the cross-sectional area of the muscle fibre after treatment at 100 degrees C decreased by 28.6% in pig, 17.8% in buffalo, 20.4% in sheep, 24.3% in goat and 34.8% in poultry, whereas the respective values after cooking at 121 degrees C were 38.3%, 28.6%, 32%, 33.9% and 44.1%. Besides, the muscle fibre diameter in all species was also reduced after cooking. The number of muscle fibres and fascicles per mm2 were found to increase after cooking at 100 degrees C and 121 degrees C.