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Studies of the effect of treatment of haddock (Melanogrammus aeglefinus) with solutions of sodium salts of ethylenediaminetetraacetic acid (EDTA) have shown that a 1% solution of tetrasodium EDTA used as a dip can extend the storage life in ice (0 C) for 11 days over that of untreated controls. The texture of these fillets remained acceptable for the whole of their storage lives.Fillets treated with 0.5 and 0.75% tetrasodium EDTA had a storage life extension of 5 days and those treated with 1% disodium EDTA had a storage life of 6 days longer than the untreated control fillets. Fillets treated with 0.5 and 1.0% disodium calcium EDTA solution showed 0- and 1-day storage life extension respectively.Increase in trimethylamine (TMA) during storage was reduced by treatment with EDTA with the tetrasodium EDTA-treated fillets having the lowest rate of increase. Samples were rejected by the taste panel as spoiled with TMA values of between 3 and 9.5 mg TMA nitrogen (TMA-N) per 100 g.Although treatment of fillets with EDTA extended the storage life in ice and suppressed the increase in TMA, there was little or no effect on the growth of the bacterial population.

Storage studies of iced irradiated scallops (Placopecten magellanicus Gmelin) have shown that treatment with a dose of 75,000 rads of gamma radiation increases the useful storage life at 0 °C with negligible changes in odour and texture. The raw scallops remained acceptable for 28 days, while the scallops assessed after cooking remained unchanged for 35 days and did not become unacceptable until 43 days storage. Doses of gamma radiation greater than 75,000 rads caused undesirable changes in texture and odour with a consequent loss of quality. Neither irradiated nor fresh iced scallops rated as high organoleptically as frozen control scallops which had been rapidly frozen in a pre-rigor condition and immediately stored at −26 °C.

Slicing cod fillets longitudinally into slices [Formula: see text] inch (13 mm) thick can increase the efficiency of candling cod fillets for codworms to over 95%. The increase is greater in the larger fillets than in the smaller fillets if sliced. If fillets are not sliced the candling efficiency decreases with increasing size of fillets.

Studies of the storage life of iced haddock (Melanogrammus aeglefinus) fillets after treatment with doses of gamma radiation of 75,000, 150,000, and 250,000 rads, have shown that a useful extension of the storage life is made possible by irradiation. The fillets irradiated with the 75,000-rad dose and assessed after cooking became unacceptable after about 25 days at 0 °C. The unirradiated control became unacceptable after 12 days. Fillets irradiated at the two higher levels were of lower quality initially than the fillets irradiated at the 75,000-rad level but showed no significant decrease in acceptability up to 27 days storage in ice. Raw fillets developed an objectionable odour and appearance just prior to becoming unacceptable to the taste panel.

Irradiation of cooked lobster (Homarus americanus) meat with a dose of gamma radiation of 75,000 rads extended the storage life, in ice, to between 28 and 35 days for both tail and claw meats from 14 to 21 days for unirradiated iced samples. Higher irradiation levels caused an immediate loss of quality due to toughening and loss of flavour. The growth of trimethylamine-producing bacteria was inhibited 10 days longer on irradiated samples than on the unirradiated iced control.