Purpose: This study was conducted to compare the effectiveness of common collection solutions at neutralizing different concentrations of representative sanitizers used in the food processing environment.
Methods: Sterile sponges, hydrated with 10 ml of either Neutralizing Buffer, Letheen Broth, or HiCap(R) were used to collect samples.
Results: Approximately 2.0 logs of Listeria were recovered from the control units and samples with the lowest concentration of sanitizers; indicating that all three collection solutions could effectively neutralize approximately 0.2 ml of residual sanitizer. Approximately 2.0 logs were recovered from HiCap and Neutralizing Buffer samples containing the 1.0 ml level of sanitizer for all three sanitizers and from the Letheen Broth samples with hypochlorite sanitizer. Only HiCap demonstrated an ability to neutralize the sanitizers at the 4.0 ml residual sanitizer level. No Listeria were recovered from the Letheen Broth samples at the 4.0 ml sanitizer level for any of the sanitizers and 0.8, 0.8, and 0.0 logs of Listeria were recovered from the Neutralizing Buffer samples with quat, peroxyacetic acid, and hypochlorite sanitizers, respectively.
Significance: Selection of a collection solution can significantly impact the accuracy of environmental surface test results.