Effects of phosphates and salt in ground raw and cooked farmed cod (Gadus morhua) muscle studied by the water holding capacity (WHC), and supported by P-NMR measurements.

A model system consisting of ground farmed cod muscle (80%, w/w) and added brine (20%, w/w) with different content and combinations of salt (0% and 3% in brine) and phosphorus compounds (mono-, di-, tri- and hexametaphosphates; 0% and 3% in brine) was used to simulate industrial brining of muscle foods. Individual phosphorus component concentrations and breakdown as function of time (0, 23 h) were analyzed using (31)P-NMR spectroscopy. The effects of salt and phosphate on water holding capacity (WHC) were measured at similar sampling times, and interrelations between phosphorous components determined by NMR and WHC were established. Addition of salt led to a significant increase (+18%) in WHC, and the combined effect of salt and phosphates was even more pronounced (+29%). The positive effect of triphosphate and salt on WHC was also seen after cooking (+36% in raw and +41% in cooked cod muscle, relative to control), although NMR analysis showed a rapid breakdown of di- and triphosphates.