REDUCTION OF SALMONELLA ON POST-CHILL CHICKEN CARCASSES BY TRISODIUM PHOSPHATE (NA3PO4) TREATMENT

The use of trisodium phosphate (TSP) in rinsing chicken carcasses was evaluated for salmonellae reduction. Post-chill carcasses were dipped into a 10%-TSP solution at 10 or 50C for 15 s. After storing 0, 1 or 6 days at 4C, the incidence and reduction of salmonellae were measured using a nitrocellulose (NC) membrane lifting technique, conventional culture methods and most probable number (MPN) technique. In a trial using non-inoculated carcasses, the incidences of salmonellae were decreased from 12 similar to 24% in controls to 0 similar to 8% in TSP-treated groups. When the carcasses were inoculated with S. typhimurium (2x10(4) CFU/carcass), the NC membrane lifting method detected 27 similar to 46% less incidences of salmonellae in TSP-treated groups. However, culture methods failed to show any difference between TSP-treated and untreated carcasses. Another trial using MPN method showed a significant reduction of salmonellae (1.6 similar to 1.8 logs) in TSP-treated groups (P<0.01) at both 1 and 6 days. Although SOC-TSP treatment gave 0.4 log greater reduction than 10C-treatment, the difference was not statistically significant. Total plate counts(TPC) revealed a similar reduction trend to MPN results of salmonellae.