Effects of high pressure on textural characteristics of cod (Gadus morhua) muscle

Comparison of the effects of pressure and heat on cod muscle showed marked differences in their effects on texture. Chewiness, gumminess and hardness of samples treated at 400 and 600 MPa increased significantly (p<0.05) when compared to the fresh and to samples treated at 200 or 800 MPa. in contrast to pressure treatment heat treatment was shown to lead to a significant (p<0.05) decrease in chewiness, gumminess and hardness. However both pressure and heat treatment has only a small effect on the springiness of samples. Furthermore, pressure treated samples (400 MPa) are harder than cooked (50 degrees C) ones (p<0.01). However cooking pressure treated caused the hardness to decrease to values similar to those found on cooking alone. It is suggested that while heat treatment gives rise to structures which are primarily stabilised by disulphide bonds and hydrophobic interactions, pressure involved myosin gels are stabilised by hydrogen and disulphide bonds.