Title: Cold Plasma Inactivates Salmonella and Escherichia coli O157:H7 on Fresh Produce Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 10, 2008
Publication Date: June 29, 2008
Citation: Niemira,B.,Sites,J. 2008. Cold Plasma Inactivates Salmonella and Escherichia coli O157:H7 on Fresh Produce [abstract].Institute of Food Technologists Annual Meeting. New Orleans,LA.p.1. Technical Abstract: This presentation will summarize recent advances in cold plasma technology at the USDA’s Eastern Regional Research Center. Cold plasma generated in a gliding arc was applied to outbreak strains of Escherichia coli O157:H7 and Salmonella Stanley inoculated on the surfaces of golden delicious apples. Cold plasma treatments resulted in significant (p<0.05) reductions from the untreated control. Inactivation followed a time-dependent reduction when plasma was applied at different flow rates of the feed gas. Maximum reductions were obtained after 180 seconds of treatment, and ranged from 2.9 to 3.7 log cfu/ml for S. Stanley, and 3.4 - 3.6 log cfu/ml for E. coli O157:H7. Temperature increase of the treated apples was also related to exposure time for all flow rates. The maximum temperature of any plasma treated apple was 50.8C (28C above ambient), indicating that antimicrobial effects were not the result of heat. Using an advanced form of the arc discharge, a treatment of 10 seconds reduced Salmonella and E. coli O157:H7 on agar plates by approximately 1 log cfu. A status summary of systems development and applications progress of these technologies will be discussed.