Investigations on the influence of gamma irradiation on boiled sausage

Ideally, preservation processes affect the status of a food as little as possible. The use of gamma radiation, which is imperceptible to humans, with its harmful effects on organisms, seems to be an obvious option for killing germs while preserving the food properties. Past investigations, however, showed very quickly that meat and meat products, among other things, can lead to massive changes in the sensory status of the food, mainly due to the release of free radicals. Therefore, the use of gamma rays as the sole preservation method is ruled out, but is fundamentally of interest as an accompanying factor to increase the shelf life of meat and meat products.

AHN et al. investigated the influence of gamma irradiation on the composition and properties of cooked sausage stored at 4 °C (Effects of gamma irradiation on residual nitrite, residual ascorbate, color, and N-nitrosamines of cooked sausage during storage). The samples were irradiated with 5, 10 or 20 kGy both under aerobic conditions and stored under vacuum and compared with the corresponding, unirradiated controls. It was shown that radiation doses above 5 kGry significantly reduced the red component of the samples, regardless of the packaging. A lower content of nitrosomyoglobin could be detected in the vacuum-packed samples. Likewise, the residual nitrite content was reduced in all irradiated samples in combination with a partial reduction in the ascorbic acid content. The levels of N-nitrosodiethylamine in the vacuum-packed samples were immediately reduced by irradiation with 5 or 10 kGy. This applied to the N-nitrosopyrrolidine content of the samples that were not vacuum-packed. With increasing storage time, this effect on the N-nitrosopyrrolidine content could also be demonstrated in the vacuumed samples. This work does not allow any conclusions to be drawn about the health risks of such preserved foods.

Source: Kulmbach [NITSCH]