Effectiveness of sanitizing agents in inactivating Escherichia coli in Golden Delicious apples

Research was undertaken to develop improved methods of sanitizing apples contaminated with Escherichia coli, Unwaxed Golden Delicious apples, inoculated with nonpathogenic E. coli, were washed with 200 ppm Cl-2, commercial washing formulations, 5% H2O2, or combinations of H2O2 with commercial formulations at ca, 20 degrees C or 50 degrees C, Heated commercial formulations achieved a 2.5 log reduction in E. coli load, compared to a 2 log reduction for 200 ppm Cl-2. However, heated combinations of H2O2 with acidic surfactants achieved a 3-4 log reduction. Residual H2O2 in treated apples dissipated within several hours. These results demonstrate the efficacy of H2O2 in decontaminating apples containing E. coli.