Herbert W. Ockerman1*, Komkhae Pilasombut**,
Jutarat Sethakul,** and Adisorn Sawetwiwat#
*The Ohio State University Department of Animal Sciences
**King Mongkut's Institute of Technology Ladkrabang (KMITL)
Department of Animal Production Technology, Thailand and
#Department of Agricultural Industry,Thailand
This experiment studied the effect of lactic acid and chlorine solutions for microbial inhibition. Lactic acid solutions of 0, 1, 2, and 3% (v/v) and chlorine solutions of 0, 20, 40, and 60 ppm were added to 108 concentrations of Salmonella derby or Staphylococcus aureus. The mixture was incubated at 0 to 4C. After 0, 1, 2, 3, 4, 5, 24, and 48 hours, colonies were counted. The result indicated that lactic acid has an anti-microbial effect. As the concentration of lactic acid increased, the number of Salmonella derby decreased (P < 0.01). Although, Staphylococcus aureus was also significantly inhibited by the lactic acid solution, the result indicated no significant differences at concentration of 1, 2, and 3% (v/v). The application of a sodium hypochlorite solution, showed a significant effect only on the number of Salmonella derby. No significant difference was found with Staphylococcus aureus, for the chlorine solutions application of 20, 40, and 60 ppm. The effect of contact time with lactic acid decreased the number of Salmonella derby significantly. The same decreasing trend was found for Stappylococcus aureus. For chlorine solutions, time of application had no effect on either the numbers of Salmonella derby or Staphylococcus aureus.
Major concern of the meat industry is to reduce foodborne pathogen particularly salmonella sp. and Staphylococcus aureus which cause a food poisoning problem. Microbiological standard for fresh meat indicates it should not contin Salmonella. In many areas of the world, it has been reported that salmonella sp, particularly salmonella derby and Staphylococcus aureus, are contaminates on fresh meat. Lactic acid is generally regarded as a safe (GRAS) substance. The U.S. Food and Drug Administration (FDA) has no limitation on the concentration of lactic acid that can be use in food products (Kotula and Theappurate, 1994). Also, chlorinated chill water has been shown to be effective in reduceing cross contamination of salmonella sp from carcass to carcass in the poultry immersion chill tank (Thomson et al., 1979). For there reason, lactic acid and sodium hypochlorite solution should be investigated for meat safety.
1For more information, contact at: 015 Animal Science Building, 2029 Fyffe Road, Columbus, OH 43210; 614-292-4317; Fax: 614-292-2929, Email: ockerman.2@osu.edu