|Porto, Anna - FORMER EMPLOYEE|
|Yoder, Lisa - HATFIELD MEAT PRODUCTS|
|Byrne, Caitriona - VISITING SCIENTIST|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 17, 2003
Publication Date: June 30, 2002
Citation: Porto, A., Luchansky, J.B., Call, J.E., Yoder, L., Byrne, C. 2002. Ability of listeria monocytogenes to withstand re-heating of frankfurters. International Association for Food Protection. Abstract # P71, p. 103. Technical Abstract: Listeria monocytogenes (Lm) has been associated with some ready-to-eat meats, including frankfurters. This study was conducted to investigate the effect of temperature, time, and product formulation on the survival of Lm on frankfurters. Individual links containing 0 or 2% potassium lactate were inoculated with approximately 8.0 log10 CFU/package of a five-strain mixture of Lm, vacuum-packaged, and stored at 4 deg C for up to 3 days. Next, frankfurters were heated to a surface temperature of 60 deg, 70 deg, 80 deg or 90 deg C for up to eight minutes by submersing the packages in a water bath. Survivors were recovered and enumerated by rinsing each package with sterile peptone water and direct plating onto MOX selective agar. The data for each of two trials were averaged: D-values at 60 deg, 70 deg, 80 deg and 90 deg C were 2.5, 0.3, 0.2, and 0.06 minutes for frankfurters containing 2% potassium lactate and 2.4, 0.3, 0.1, and 0.06 minutes for frankfurters without added potassium lactate, respectively. Similar result were obtained using frankfurters inoculated with Lm and stored at 4 deg C for 15 days and at -18 C for 30 days prior to cooking. In general, statistical analyses revealed a significant (P less 0.05) decrease in D- values with an increase in temperature. Product formulation did not appreciably affect D-values for any of the parameters tested. These findings estalish cooking guidelines that can be followed by consumers to ensure that frankfurters, which may be contaminated with low levels of Lm after unpackaging, are adequately re-heated before consumption.