Determining the Effect of Whitening Agents on Physico-chemical and Functional Properties of Sardine Surimi (Sardina pilchardus)

The effects of treatments with calcium carbonate (CaCO3), sodium bicarbonate (NaHCO3), and hydrogen peroxide (H2O2) were investigated in order to enhance the whiteness and functional qualities of sardine surimi (Sardina pilchardus). To explore their effects and establish the ideal dosages of each whitening agent utilised, Principal Component Analysis (PCA) was used. Total 13 treatment lots were made as follows: control (conventional washing process), surimi treated with whitening agents at three concentrations for each one (H2O2 (1%; 1.5%; 2% and 2.5%), NaHCO3 (0.1%; 0.3%; 0.5% and 0.7%) and CaCO3 (0.5%; 0.75%; 1% and 1.5%)). The study's findings showed that addition of CaCO3 and H2O2 significantly improved whiteness of surimi in comparison to NaHCO3 treatments (p < 0.05). Some textural damage and a reduction in WHC values were observed for surimi treated with H2O2 and NaHCO3 (p < 0.05). Since 1.5% CaCO3 sample lies closer to these functional attributes vector lines than the other treatments, PCA biplot demonstrated that 1.5% CaCO3 tended to improve whiteness, WHC, and textural features. Whereas, 2.5% H2O2 had positively affected only the whiteness parameter.

The findings showed that adding the right kind and amount of whitening agent to mince can enhance its functional qualities, especially when it comes from fish species with darker meat, like sardines.