Low‐level heat‐treatment to extend shelf‐life of fresh fish

The application of heat to reduce the microbial load and extend the lag phase was studied on whole fish and with bacterial isolates from fresh fish in mixed culture. Bacterial isolates obtained from fresh horse‐mackerel (Trachurus trachurus) were heat treated at 60°C for 20s and stored in nutrient broth on ice. the flora were shown to be heat sensitive and the initial numbers were reduced by over 2.0 log₁₀ cycles. Heating at 60°C extended the lag phase but subsequent growth rates were increased, giving a shelf‐life extension of a day and a half. There were no significant effects on visual EC grades of whole fish or on the flavour of cooked fillets.