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 ∼ 24% in controls to 0 ∼ 8% in TSP‐treated groups. When the carcasses were inoculated with S. typhimurium (2×104 CPU/carcass), the NC membrane lifting method detected 27 ∼ 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 ∼ 1.8 logs) in TSP‐treated groups (P < 0.01) at both 1 and 6 days. Although 50C‐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.