The effect of phosphate solutions on the denaturation of frozen cod muscle

Summary The effect of treating cod fillets with phosphate solutions prior to freezing was studied. Little influence on subsequent denaturation of the cold stored material was found, as measured by protein extractability in dilute salt solution. However, the treatment invalidated the cell fragility method by producing very low values. Electron microscopy showed that these were the result of the solvent action of the phosphate solutions, which removed some of the protein from the myofibrils and made the cell fragility homogenate correspondingly less dense. Some of the dissolved protein was shown to be deposited on the surface of treated fillets, and it is the resulting film which probably seals the fluids in the fillet and causes the well‐known reduction in thaw‐drip.