Influence of sodium chloride and its combination with Fe (II) or Cu (II) on the oxidative alteration of butter model systems

Abstract

The effect of the incorporation of different levels of NaCl at 10.7, 21.4, 46 and 66 g kg^-1, and the combinations of NaCl (10 or 20 g kg^-1) and Fe(II) or Cu(II) (25 or 50gg^-1) in model systems of water dispersion in butter fat (WDIBFS) during storage was investigated by measuring peroxide value, p-anisidine index and TOTOX. The results indicated that NaCl at 10.7, 21.4 and 46 g kg^-1 levels had a significant retarding effect against fat oxidation during 6 months of storage, while the higher concentration of 66 g kg^-1 salt showed a significant prooxidant effect. NaCl significantly (p 0.05) increased the prooxidant effect of Cu(II) in all combinations, whereby the increase was directly proportional to the salt concentration. On the other hand, the addition of NaCl significantly increased the prooxidant effect of Fe(II) ions with no significant differences between the two salt levels (10 and 20 gkg^-1). Ferrous ions were more effective as prooxidant than Cu(II) ions in the salt free WDIBFS. However, the addition of salt almost canceled the observed differences of the prooxidant influence of Fe(II) and Cu(II) ions.