|YUANYUAN - Jiangnan University|
Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/1/2021
Publication Date: N/A
Interpretive Summary: We have recently demonstrated that cold plasma-activated hydrogen peroxide reduced populations of bacteria on the surfaces of various fresh produce items. However, the residue levels of hydrogen peroxide, a strong oxidizing agent, on treated fresh produce have not been quantified. In the present study, the residue on apples, tomatoes, cantaloupe, and Romaine lettuce was analyzed after treatments with activated hydrogen peroxide at conditions that achieved maximum reductions of Salmonella. Results showed that levels of residue on fresh produce surfaces decomposed rapidly and did not pose a safety concern. The information would help facilitate the commercialization of the novel technology.
Technical Abstract: Hydrogen peroxide (H2O2) has long been studied as an aqueous sanitizer to enhance microbial safety of fresh produce. Recently, we demonstrated that cold plasma-activated H2O2 aerosols, hereafter referred to as ionized hydrogen peroxide (iHP), reduced populations of Salmonella, Listeria, and E. coli by up to 5.5 logs on surfaces of various produce items. However, the amount and fate of H2O2 residue left on fresh produce after treatments have not been evaluated. In the present study, H2O2 residue levels on apples, tomatoes, cantaloupe, and Romaine lettuce were analyzed after treatments with 7.8% iHP at conditions that had been optimized and tailored for Salmonella reductions and each produce items. Results showed that higher residue levels were found on lettuce than on cantaloupes, tomatoes and apples immediately after treatments. During storage at 10 and 22°C, H2O2 levels decreased rapidly and fell below <1 mg/kg within 1 day after treatments for all fresh produce items. Furthermore, the decrease was faster at 22°C than at 10°C. Most importantly, the levels of H2O2 residue on the fresh produce items were lower than those after wash with 1% H2O2 for 1 min. Overall, our results demonstrated that levels of H2O2 residue on fresh produce surfaces decomposed rapidly after treatment with iHP and did not appear to pose a safety concern after 1 day of storage.