INCORPORATION OF NISIN INTO A MEAT BINDING SYSTEM TO INHIBIT BACTERIAON BEEF SURFACES

In two separate experiments, the bacteriocin, nisin, was incorporated into a commercially available meat binding system (Fibrimex(R)) and ap plied to meat surfaces as a way inhibiting the meat spoilage organism, Brochothrix thermosphacta during extended refrigerated storage. In ex periment 1, pre-rigor lean beef carcass tissue (BCT) was inoculated wi th B. thermosphacta, left untreated (U), treated with 10 mu g ml(-1) n isin (N), Fibrimex(R) (F) or Fibrimex(R) containing 10 mu g ml(-1) nis in (FN), held aerobically at 4 degrees C for up to 7 d, and population s of B. thermosphacta and nisin activity determined. Experiment 2 dete rmined the effects of the same treatments but on post-rigor, frozen an d thawed lean BCT that was inoculated, vacuum-packaged, and stored at 4 degrees C for up to 14 d. In both experiments, N- and FN-treated tis sues exhibited significantly lower populations of B. thermosphacta com pared to U- and F-treated tissues, for the duration of refrigerated st orage. Nisin activity was detected up to 7d in N- and FN-treated sampl es from experiment 1. However, activity was detected only to days 0 an d 2 in FN- and N-treated samples, respectively, from experiment 2. The se studies indicate that the addition of a bacteriocin to a meat bindi ng system and application to meat surfaces may be useful in reducing u ndesirable bacteria in restructured meat products.