Influence of lactic acid on the survival of Salmonella on poultry carcass surfaces

摘要

The aim of this study was to determine the influence of different lactic acid concentrations on Salmonella bacilli in microbiological media and on the surfaces of chicken carcasses. For the contamination of samples the following strains were used: Salmonella Enteritidis, Salmonella Typhimurium, Salmonella Hadar, Salmonella Infantis and Salmonella Virchow. Each strain from each dilution was placed on nutrient agar without the addition of chemical substances (the control), and on nutrient agar with various amounts of substances were added 0.02%, 0.05%, 0.1%, 0.25%, 0.5%, 1%, 2% solutions of lactic acid. A concentration of up to 0.02% of lactic acid did not have a significant effect on the quantitative growth of Salmonella spp. Starting from the concentration of 0.1%, lactic acid completely inhibits the growth of all the studied strains of Salmonella. 150 samples from broiler chicken breasts were immersed for 2 minutes in 80 ml of Salmonella suspension containing 10(7) CFU. The samples were then transferred to sterile beakers with 250 ml of 2% and 5% solutions of lactic acid for a period of 5 minutes. Compared to the control, at a lactic acid concentration of 2% the number of Salmonella reductions ranged from 0.18 to 1.21 log. At the lactic acid concentration of 5%, the number of Salmonella, compared to the control, reductions ranged from 2.69 log to 3.67 log. From the conducted tests it can be concluded that it is possible to reduce the number of Salmonella bacilli on the surfasses of chicken carcasses through lactic acid concentrations of at least 2%.