Chemical Properties of Oils in Gamma-Radiated Fish Meat and Products-Part I

When fish or its products are subjected to the gamma radiation for preservation, their taste is often degenerated, and there are reasons to assume that this is caused by changes in chemical properties of oil contained in fish. The aim of the present study is to find out means, if any, to avert the degeneration of the taste in as much as the assumption is proved true. In the experiments conducted for this purpose, the authors have found that when the fatty abdominal meat of tuna is exposed to the gamma radiation from a cobalt-60 isotope (radiation dose 1, 000, 000 r), it shows a dark brown color with an offensive ordor, the oil of the meat turning rancid (Table 2). On the other hand, fish sausages irradiated did not show, despite the presence of an amount of fat, any remarkable changes as to palatability (Table 3 and 4).