Gamma radiation effect on quality changes in vacuum-packed squid (Illex argentinus) mantle rings during refrigerated (4-5°C) storage

Abstract

The effect of gamma radiation (0, 1.8, 3.3 and 5.8kGy) on microbiological, chemical and colour characteristics of vacuum-packed squid (Illex argentinus) mantle rings was studied. Total viable counts; psychrotrophic bacteria counts, Escherichia Coli, Staphylococcus aureus and Clostridium perfringens; total volatile basic nitrogen (TVBN) and colour difference were analysed during 29days of storage at 4-5°C. Higher doses of gamma radiation significantly reduced Total Viable, phychrotrophic counts and TVBN production (P<0.05) in a dose-dependent way, delaying squid spoilage. Colour difference of non-irradiated samples with respect to first day significantly increased while it was constant in radiated samples during 22days (P<0.05). Independently from the dose, radiation avoided colour changes of squid rings. Gamma irradiation was effective in delaying deterioration reactions, improving microbiological, chemical and colour quality of vacuum-packed squid rings stored at 4-5°C.