Use of natural antimicrobials to extend the shelf-life of vacuum-packaged cooked cured meats

Abstract

Typical spoilage microorganisms, 'Leuconostoc mesenteroides ' ssp. 'mesenteroides', 'Lactobacillus sakei ' and 'Lactobacillus curvatus', were subjected to a variety of preliminary testing against natural antimicrobial agents derived from spices (eugenol, allyl isothiocyanate), an organic acid (potassium lactate), a fatty acid (monolaurin), and lactic acid bacterial fermentations (bacteriocins--Alta (R) 2341 and Alta Mate(R)). The inhibitory activity of these agents was tested in mixtures which included an aqueous extract of wood smoke (liquid smoke) and a variety of phosphates and phytic acid as metal ion chelators. Individual inhibitors and their combinations were tested against bacteria in broth and agar diffusion tests where a variety of formats were used. Some of the tests used included monitoring changes in viable bacterial numbers or optical density in broth as well as formation of inhibition zones around discs or wells made in agar inoculated with test organisms. As the work progressed, 'Lb. curvatus' was eliminated from testing because all three organisms showed similar sensitivity profiles, but the two bacteria retained for further study demonstrated greater overall resistance. (Abstract shortened by UMI.)