Assessment and Control of Foodborne Pathogens in Ireland

Abstract

Consumers are increasingly demanding food that is free from pathogens, but with less preservatives and additives. As a response to these conflicting demands, current trends in the food industry include minimal processing, and the investigation of alternative inhibitors for use in foods. Additionally, the manufacture of an increasing range of novel foods, and the inclusion of non-dairy ingredients into dairy products, and vice versa, poses additional dangers with respect to safety. Furthermore, the dramatic increase in incidence of food-borne illness internationally, as a result of contamination with food-borne pathogens such as Listeria monocytogenes, is a cause of considerable consumer concern. Bacteriocins are inhibitory peptides produced by a number of Lactic Acid Bacteria which are capable of killing other bacteria. These natural inhibitors have widespread applications in the preservation of foods, since they can kill a number of pathogenic and spoilage bacteria. The broad spectrum bacteriocin Lacticin 3147 (discovered in a previous project and patented - see DPRC No. 3) is produced by Lactococcus lactis subsp. lactis DPC3147, a food-grade strain, similar to strains used for commercial cheese manufacture. Lacticin 3147 is effective in the inhibition of all Gram positive bacteria tested including the food pathogens Listeria monocytogenes and Staphylococcus aureus and food spoilage bacteria such as Clostridia and Bacillus species. As part of this project the bacteriocin Lacticin 3147 was assessed as a food preservative for improving food safety via inhibition of pathogenic organisms. Thus the project plan followed a "twin-track" approach to assessing and controlling the food safety aspects of Irish food. The first of these was designed to investigate the current safety status of Irish dairy products. The second approach involved an attempt to exploit natural antimicrobial substances, including Lacticin 3147, to protect foods from pathogenic bacteria.