Establishing luminescence methods to detect irradiated foods

摘要

Since 1989, Ministry of Agriculture, Fisheries and Food (MAFF) funded research into the luminescence detection of irradiated foods has been undertaken at SURRC. Initial work on the origins of thermolumi-nescence (TL) demonstrated that TL is associated with silicate minerals present as contaminants in herbs and spices, and formed the basis, following interlaboratory trials, for the United Kingdom (UK) validated and current European standard methods. As a result of the extension of TL methods to fruits and vegetables and shellfish, MAFF commissioned further international collaborative trials to assess the case for validation. These trials were initiated in 1996, have recently been completed and are described briefly below. The photo-stimulated luminescence (PSL) method developed at SURRC provides both a rapid screening technique, and in combination with calibration or with a confirmation technique (eg TL), a reliable means of confirming compliance with labelling regulations. PSL systems are now being used in a number of UK and overseas laboratories. With this in mind the MAFF trials were extended to include PSL analysis of shellfish and herbs, spices and seasonings.