Survival of Arcobacter butzleri on vacuum packaged chill stored beef

The ability of Arcobacter butted to survive and the effect of initial cell numbers on their survival on vacuum packed chill stored beef were examined. In addition, the effect of natural microflora present on commercial beef on the survival of A. butzleri under vacuum packaged chill stored conditions was also examined. The numbers of A. butted on sterile beef cores stored under vacuum packaged conditions at -1.5 or 4 degrees C dropped significantly (P<0.05) over the time of the study (6 wks). In contrast, survival of A. butzleri on commercial vacuum packaged beef (beef with natural microflora) was significantly (P<0.05) enhanced, resulting in only 03 and 13 log cfu cm(-2) drops in numbers at -1.5 degrees C and 4 degrees C, respectively, at the end of 6 wks. Survival of A. butted on sterile beef cores inoculated with higher initial numbers was significantly (P<0.05) higher than on core inoculated with lower initial numbers, while on commercial vacuum packaged beef initial A. butted numbers had no significant (P>0.05) effect on its survival. Cores inoculated with similar to 10(6) cfu cm(-2) A. butted, irrespective of storage temperature or packaging conditions, could be enumerated by direct plating up to day 35. However, cores inoculated with similar to 10(4) cfu cm(-2), irrespective of packaging conditions, A. butted could be enumerated by direct plating up to 28 and 21 days from cores held at -1.5 and 4 degrees C, respectively. On commercial vacuum packaged beef, irrespective of initial inoculated A. butted cell numbers or temperature of storage, A. butted could be enumerated by direct plating even at 6 wks (end of the study). The presence of inoculated A. butted on commercial vacuum packaged beef, irrespective of the initial cell numbers had no significant (P>0.05) effect on the natural microflora numbers compared to uninoculated controls. These results show that natural microflora on commercial vacuum packaged beef afford enhanced survival of A. butted, irrespective of their initial cell numbers on the surface of beef stored at industry standard vacuum packaging and chill stored conditions. These findings reinforce the requirement for strict hygienic practices or the implementation of decontamination technologies to ensure safety of beef with respect to this pathogen. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.