Irradiation to ensure the safety and quality of prepared meals. Results of the coordinated research project (2002-2006)

The consumption of prepared meals has increased enormously during the last decade, not only in developed countries but also in developing countries where many types of ethnic foods are now also prepared as convenience foods. Consumer studies carried out on the consumption of these types of foods have shown that perceived time pressures contribute positively to the purchase of both prepared meals and takeaway meals. Other reasons are also mentioned in the literature, among them are the increasing proportion of working women outside of the home, not enjoying cooking for oneself and the need of family members to eat at different times. Traditionally, prepared meals are retort processed, or, more recently, stored frozen, whereas an increasing demand exists for chilled commodities, partly due to their fresh appearance. However, the chilled prepared meals are non-sterile and potential survival of some pathogenic microorganisms and/or post-processing contamination before packaging creates microbiological risks and a considerable limitation of shelf life. This is particularly important for countries where the microbiological safety of many ethnic prepared meals is questionable and their shelf life limited due to the conditions under which they are produced, stored and distributed. Food irradiation used on its own, or in combination with other technologies, could significantly enhance the microbial safety of such products as well as extend their shelf life. Although extensive research has been carried out on the microbiological, chemical, nutritional and sensorial effects of irradiating individual uncooked food items, little work has been reported on the irradiation of complex food systems such as prepared meals. In 2002, the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture initiated in a Coordinated Research Project on Irradiation to Ensure the Safety and Quality of Prepared Meals. This project included the studies of participants from different regions of the world. In total, more than 50 different prepared meals were investigated. This publication presents the results of studies conducted over a five year period (2002-2006) on the safety, shelf life and overall quality of the meals stored under ambient, chilled or frozen conditions