Antimicrobial activity of cell-free supernatant of lactic acid bacteria on spoilage bacteria of vacuum-packed sliced emulsion-type sausages.

BACKGROUND

Spoilage is very common in vacuum-packed sliced emulsion-type sausages during refrigerated storage. This study aimed to investigate the inhibitory effects of cell-free supernatant (CFS) of lactic acid bacteria (LAB) on the spoilage bacteria isolated from vacuum-packed sliced emulsion-type sausages as biological preservatives.

METHODS

These products from various companies were examined to find the spoilage bacteria. A total of 43 LABs were screened for inhibitory activity against the spoilage bacteria. The MIC of protective bacteria and the inhibitory effect of different components obtained from these bacteria was investigated.

RESULTS

Four LAB were confirmed as the predominant spoilage bacteria, including Enterococcus mundtii, sakei Latilactobacillus curvatus, and Weissella viridescens. Six strains, including ATCC 4356, PTCC 1332, CEC 17484, LL441, ATCC 53103, and DSM 20284 were able to produce proteinaceous antimicrobial metabolites against the four spoilage agents, which were selected as protective bacteria. CFS of the protective bacteria inhibited four spoilage bacteria by more than 88%. The MIC of all protective bacteria was less than 10 mg/ml against and . After neutralizing acid and HO of the CFS of , it was still quite effective against and . The sausage's pasteurization temperature did not affect the bacteria's active metabolites.

CONCLUSION

The substances derived from these bacteria can be applied as biopreservatives in sliced sausage, even in the pre-pasteurization stage of these products.