CONTROL OF LISTERIA MONOCYTOGENES AND STAPHYLOCOCCUS AUREUS IN MEAT AND MEAT PRODUCTS BY CELL-FREE SUPERNATANT OF BREVIBACILLUS LATEROSPORUS BGSP7 AND BGSP9

Abstract

The presence of pathogens in food has increased awareness of food safety, but it also causes large economic losses. Fresh meat and meat products contain a sufficient quantity of proteins, lipids, water, and a favorable pH that stimulates the growth of various microorganisms, including pathogens.

The aim of this study was to investigate the efficacy of Brevibacillus laterosporus BGSP7 (CFS-BGSP7) and BGSP9 (CFS-BGSP9) cell-free supernatants in the control of Listeria monocytogenes and Staphylococcus aureus in raw meat and meat products.

Raw meat and meat products were sliced and then aseptically treated by immersion for 2 minutes into solutions containing: i) CFS-BGSP7; ii) CFS-BGSP9; iii) no treatment. The samples were then artificially contaminated with: Group I – L. monocytogenes (~4 log cfu g-1); Group II – S. aureus LMM322 (~4 log cfu g^-1). Each sample was individually aseptically vacuum-packed and stored at 4°C for 8 weeks. The number of surviving bacteria in the samples were analyzed immediately after contamination with L. monocytogenes and S. aureus and at regular time-intervals: after 1, 3, 5 and 8 weeks of storage at 4°C.

Meat samples treated with CFS-BGSP7 and CFS-SP9 showed a significant decrease in the cell counts of L. monocytogenes and S. aureus. When meat samples treated with CFS-BGSP7 and CFS-BGSP9 are compared, the results show a more intense reduction rate of both L. monocytogenes and S. aureus in all samples treated with CFS-BGSP7.