Effects of gamma-irradiation upon biogenic amine formation in Egyptian ripened sausages during storage

The effects of gamma-irradiation upon the biogenic amine inventory in Egyptian fermented sausages were investigated during storage for up to 30 days. Typical contents of biogenic amines in non-irradiated sausages ranged between 277 and 5815 mg/kg(DW); irradiation with 2,4 and 6 kGy decreased the total contents to 186-111, 188-98 and 180-57 mg/kg(DW) by the end of storage, respectively. Cadaverine was the major amine in non-irradiated samples - where it accounted for 44\% of the total by 30 days: however, tyramine dominated in irradiated samples, where it accounted for 50\%. On the other hand, the histamine content in non-irradiated sausage by 30 days of storage (i.e. 768 mg/kg(DW)) clearly exceeded the maximum allowable of 100 mg/kg, unlike happened in their irradiated counterparts. Therefore, the dramatic reduction observed in the histamine levels suggests that the use of this preservation technique will be beneficial for such a traditional processed meat. Industrial relevance: Traditional fermented sausages are a major food product in the Egyptian market, which consists of more that 70 million people. However, there are safety problems regarding this product owing to microbial contamination during processing that leads to biogenic amines; fermentation resorts only to its adventitious microflora (which in addition effect proteolysis, thus releasing free amino acids) and no thermal treatments are allowed (that would disturb its unique flavour). Hence, irradiation is in principle a promising alternative for industrial level production - viz, in controlling said biogenic amines. This manuscript addresses the lack of data in this particular field of obvious industrial interest. (C) 2010 Elsevier Ltd. All rights reserved.