Destruction of salmonella enteritidis in poultry feed by combination of heat and propionic acid

A factorial laboratory experiment was conducted to assess the effects of heating times of 0, 20, 40, and 80 sec at 160 F and propionic acid concentrations of 0, 0.1%, and 0.2% on reduction of Salmonella enteritidis in poultry feed with approximately 15% moisture. The results showed that after 80 sec heating time an approximately 10,000-fold reduction in living salmonella was obtained in the samples with 0.2% propionic acid. Survival in the 0.2% acid group was 2 log₁₀ lower than in the 0.1% and control groups. This difference was statistically significant. Multivariate analysis with repeated measures showed there was no interaction between heating time and propionic acid concentration (P < 0.4113). There were overall significant effects for both acid concentration (P < 0.0001) and heating time (P < 0.0001).