| Abstract: | The microbial decontamination of chicken feed, obtained from a commercial pellet mill, was evaluated using a direct-fired steam conditioner (DFSC; APC System?). The standard plate count of the feeds before (mash) and after (pellets) conditioning ranged from 65×104 to 83×105 colony forming units (CFU) g?1 and from 91×101 to 92×103 CFU g?1, respectively. The incidence of Escherichia coli , Salmonella and Listeria in the feeds before conditioning was 61·7, 8·3 and 27·1%, respectively. Following conditioning these levels were reduced to 1·7, 1·7 and 0%, respectively. Species of Listeria and Salmonella identified included L monocytogenes , L innocua and S agona , S ohio , S heidelberg , S senftenberg , S tallahasse and S braenderup , respectively. Compared with a conventional, indirect-fired boiler-generated-steam conditioner (IFSC) the direct-fired steam conditioner proved superior in regards to pathogen decontamination; no E coli , Salmonella or Listeria were recovered from mash lots positive for these microorganisms. However, with the IFSC system, both E coli and L monocytogens were recovered at levels of 11·1 and 5·6%, respectively. |
