Radurisation process for Indian salmon /Eleutheronesma tetradactylum/ and black pomfret /Parastromateus niger/

A radurization process comprising anaerobic packaging, irradiation at 0.1 Mrad and storage at 0-20C has been described for the extension of shelf-life of Indian salmon and black pomfret. The radurized fillets showed an extension of shelf-life up to 20-25 days without much change in natural freshness characteristics as against the unirradiated controls which spoiled within 8-10 days. Fillets exposed to higher doses of 0.2 or 0.3 Mrad and stored under aerobic conditions manifested oxidative changes in the form of rise in TBA (2-thiobarbituric acid) reacting substances and formation of rancid odours. Anaerobic packaging minimised these changes. Solubility of heme pigments decreased by 50-70% during storage in ice of fillets exposed to 0.2 or 0.3 Mrad. This effect was more pronounced during aerobic storage conditions as compared to anaerobically stored fillets. (F.J.)