Ultrastructure of mechanically tenderised pork muscle

Porcine biceps femoris muscles were mechanically tenderised by the use of a meat activator. The kind and degree of damage of muscle tissue were then examined under an electron microscope. It was observed that several changes, known from the studies of the post mortem muscles, were much more frequent in tenderised than in intact muscles. Additional changes were found as: disruption of the contractile system or its expansion till the A- and I-bands disconnected. Thus we suggest that mechanical tenderisation, by destroying several linkages between muscle fibres, between myofibrils and within myofibrils, may be responsible for lattice expansion and increase of brine uptake and overcoming the myofibrillar and connective tissue toughness of porcine meat.