45F-2 |
Efficacy of 1% hydrogen peroxide wash in decontaminating apples and cantaloupe melons |
G. M. SAPERS and J. E. Sites. Food Safety Intervention Technologies Research Unit, USDA-ARS-Eastern Regional Research Center, 600 E. Mermaid Ln., Wyndmoor, PA 19038-8598 Improved methods of decontaminating fruits and vegetables are needed to reduce the risk of produce-related foodborne illness. Previous studies have demonstrated efficacy of 5% hydrogen peroxide in inactivating E. coli on artificially contaminated apples. Recent action by the U.S. Environmental Protection Agency now exempts use of up to 1% hydrogen peroxide, applied post-harvest to agricultural food commodities, from the requirement of a tolerance. Our objective was to investigate efficacy of 1% hydrogen peroxide in decontaminating apples and cantaloupes containing human pathogens. Apples inoculated with Escherichia coli (ATCC 25922, 3 cider outbreak strains of O157:H7, or a 5-strain O157:H7 cocktail) were washed with 1% hydrogen peroxide at 20 or 40 °C for 15 or 30 min or with 200 mg/L chlorine (as hypochlorite). Cantaloupes were inoculated with E. coli 766 (ATCC 9637, a surrogate for Salmonella Poona) and given the same wash treatments. Surviving populations were enumerated on TSA, overlayed with MAC to allow for recovery of injured cells. Hydrogen peroxide stability was monitored during treatment application. To confirm promising results, selected laboratory-scale washing treatments were applied in a pilot plant-scale wet dump tank. Population reductions obtained with inoculated apples were between 2 and 3 logs for all E. coli strains and treatments, equal to or greater than reductions obtained with 200 mg/L chlorine. However, these treatments were ineffective against E. coli 766 on inoculated cantaloupes. Apple treatments were carried out successfully in the dump tank. Hydrogen peroxide solutions were stable during treatment application and effective in inactivating E. coli, even in the presence of leached apple soluble solids. Our results indicate that treatment with 1% hydrogen peroxide is a potential alternative to use of chlorine in sanitizing apples. This treatment can be applied in a dump tank, equipment that is widely available to fruit packers.
Session 45F, Fruit & Vegetable Products: Fruits (Fresh)
|