Effects of type and concentration of salts on physicochemical properties in fish mince

- KCl and MgCl2 were used as NaCl -replacer in a cooked haddock mince.
- Ionic strength had more effect on cooking loss than type of cations.
- Replacing NaCl with MgCl2 decreased WHC, pH and breaking force.
- MgCl2 gave lower cooking loss compared to KCl and NaCl at same concentration.
- WHC for minces made with NaCl decreased when fresh fillets were replaced with frozen.

Cooked minces made from both fresh and frozen haddock with NaCl, KCl, or MgCl2 at concentrations from 0.07 to 0.34 mol/kg fish mince were prepared and analysed for physicochemical properties. The properties of the minces varied both with the type and amount of added salt. Minces added the same molar amount of NaCl or KCl had fairly similar properties, but pH in minces made with KCl was slightly higher. Minces made with MgCl2 had lower pH than the corresponding minces made with NaCl. Minces made from fresh raw material with 0.07 mol/kg MgCl2 had significantly lower WHC than the rest of the minces, while minces made with 0.34 mol MgCl2/kg had lower moisture and breaking force than the corresponding minces with KCl or NaCl. Low field NMR T2 relaxation data indicated differences in the protein structure as an effect of addition of small amounts of salt. Cooking loss decreased with increasing salt content both when fresh and frozen raw materials were employed, and the results indicate that this could be due to the increased ionic strength. WHC for minces made with NaCl decreased significantly, whereas WHC did not change much for minces made with KCl or MgCl2.