Effects of natural preservative and modified atmosphere packaging on shelf-life of sliced beef ham

The influences of natural preservative and modified atmosphere package on the shelf-life of sliced beef ham stored at 9℃ under fluorescence lighting conditions were studied with vacuum-packaged products as controls. The results show that the number of Lactobacilli in the vacuum-packaged products grow rapidly and exceeded 6.70 log(cfu·g)^-1 at 28 d with continuous decline of pH values. The growth of lactic acid bacteria is not retarded in the modified atmosphere package(MAP)(60%CO₂+40%N₂). The a^* values(redness) of MAP products decrease significantly(p<0.05). The natural preservative(150 mg/kg Nisin + 0.3% tea polyphenols) has significant bacteriostatic activities against Lactobacilli, and the effects of bacteriostatic are better by dipping after slicing(DAS) than that by incorporation before curing(IBC). During storage, the a^* values of products are not affected by natural preservative(p<0.05). The MAP or natural preservative has little effects on TBARS changes.