The determination of efficacy of antimicrobial rinses on turkey carcasses using response surface designs

Chlorine, lactic acid, TSP (trisodium phosphate) and a commercial phosphate blend (AvgardTM) were evaluated for their potential bactericidal effects on faecally contaminated turkey carcasses. Carcasses were sprayed for 10 s with each bactericide, at various concentrations and pressure combinations, derived from a response surface central composite design. For all the bactericides, variation in pressure had no significant (P . 0.05) effect in reducing either total or coliform counts. Lactic acid at various concentrations showed a significant effect (P < 0.20) in reducing total and coliform counts. The results indicate that lactic acid at 4.25% (ww) has the potential for reducing the total microbial load and coliforms by more than 95%. Chlorine, TSP and AvgardTM concentration did not significantly (P > 0.20) affect the microbial load when compared with a water spray, i.e. no bactericide. Preliminary presumptive testing indicated that lactic acid and AvgardTM had some effect against Salmonella spp. Chlorine and TSP, irrespective of concentration and pressure, were not effective against Salmonella spp. Overall, these findings suggest that lactic acid was the most effective bactericide for reducing microbial contamination and improving the safety of poultry meat.