Studies on the combined effect of gamma radiation and cooking on the nutritional value of fish

Abstract

The effect of irradiation (0.6 Mrad), cooking and a combination of both treatments has been measured on the protein nutritive value and on the B-complex vitamins, nicotinic acid, riboflavin and thiamine, in cod fish fillets. Microbiological assay methods were used throughout. Protein nutritive value was unaffected by irradiation, whereas cooking caused a 9% loss: this loss was not increased by prior irradiation treatment. Irradiation did not affect nicotinic acid and a 4 % loss caused by cooking was again not increased by a combination of treatments. Riboflavin was reduced 6 % by radiation, 9 % by cooking, and 16% after both treatments, whilst for thiamine the losses were 47% by radiation, I0 % by cooking and 54 % by combined treatment.It was concluded that irradiation followed by cooking produced a total loss which was the sum of the losses produced by each treatment. The importance of loss of nutrients in fish due to radiation processing is discussed.

Radiation Processing to Improve the Quality of Fishery Products

“…No loss of niacin in cod fillets irradiated at 6 kGy and kept on ice for 7 days has been reported. 148 Similar results have also been reported with respect to irradiated (10 kGy) ground mackerel and cod fillet. 291 In general, irradiationdependent loss of vitamins was not significant.…”

“…66 The nutritional quality of irradiated foods, including seafoods, has been investigated in detail. 2,148,291 The effect of irradiation on chemical changes in the foods depends on a variety of factors such as initial food composition, temperature during irradiation, as well as treatment conditions such as radiation source used, dose rate, and absorbed dose. The changes that occur are quite negligible especially at lower doses and therefore are difficult to detect in treated foods.…”

Effect of gamma irradiation on the keeping quality and nutrients of tilapia (Oreochromis mossambicus) and silver carp (Hypophthalmichthys molitrix) stored at 1.C

“…Thiamin losses of raw pork irradiated at 0.57 and 1.91 kGy were 7.7 and 23.5 respectively; post-irradiation cooking resulted in additional thiamin loss of about 11 YO (Jenkins et a1 1989). Thiamin in cod was reduced 47% by radiation at 6.0 kGy, 10% by cooking and 54% by combined treatment (Kennedy and Ley 1971). It is apparent that thiamin content in foods decreased as irradiation dose increased.…”

Impact of Irradiation on Fish and Seafood Shelf Life: A Comprehensive Review of Applications and Irradiation Detection

“…Przybylski et al, 1989 Cultured channel catfish (Ictalurus punctatus) 0, 0. (Continued on next page) The 2 processes produced a total loss which was the sum of the losses produced by each process regarding niacin, riboflavin and thiamin Kennedy and Ley, 1971 98 Downloaded by [MacEwan University Libraries] Rhodes et al (1964), found that the optimum irradiation dose was 1-3 kGy. However, this was based only on appearance and odor.…”

“…Panelists found that the odor of irradiated Kwamegi was better than that of control and indicated that a unique fishy off-odor of the saury decreased in irradiated samples. Kennedy and Ley (1971) measured the effect of irradiation (6 kGy) and cooking on niacin, riboflavin, and thiamin in cod fish fillets, and concluded that irradiation followed by cooking produced a total loss which was the sum of the losses produced by each treatment.…”