| Abstract: | Formaldehyde formation and reaction with muscle proteins in lean fish species during frozen storage is considered to be a major factor affecting texture and functionality deterioration. Formaldehyde formation and reaction with muscle compounds was reduced in lean fish minces and model systems when lipids with different degrees of oxidation were added. In order to increase the lipid content and slow down functional and textural changes, hake (Merluccius merluccius) and sardine (Sardina pilchardus) minces mixed in the ratios 3:1; 1:1 and 1:3 (w/w) were stored at ?20 °C and studied for 1 year. Dimethylamine formation and, by deduction, formaldehyde formation increased. However, less free formaldehyde was detected, probably owing to reaction with muscle compounds in the mixed minces. Nevertheless, addition of sardine minces improved the texture, protein solubility and viscosity of the mixed minces compared with the hake minces. In the mixed lots, formation of large protein aggregates was delayed or prevented. This suggests that in the mixed minces formaldehyde reacted with proteins in a different way from that in lean fish or reacted with other muscle components not directly involved in textural changes. © 2002 Society of Chemical Industry |
