Use of a Nanotechnology Surface Coating (BioShield®75) Against Foodborne Pathogenic Bacteria

Abstract

Biostatic agents that are intended for surface application can inhibit the growth of microorganisms, and their use is becoming increasingly popular throughout the food industry (1). BioShield®75 is a surfactant designed to inhibit microorganisms through the use of the Octadeylaminodimethyltrihydroxysilylpropylammonium chloride molecule. This compound is in the family of quaternary ammonium antimicrobials and was tested against two common foodborne bacteria, Listeria monocytogenes and Salmonella. Stainless steel coupons were used to simulate a typical food processing surface. BioShield®75 was applied to half the coupons, with Salmonella and Listeria monocytogenes applied to all. After storage at room temperature for two hours, the coupons were enumerated on trypticsoy agar (TSA); a nonselective media. This media was effective because only one bacteria strain was on each coupon at a time therefore selective media wasn’t needed. After plate counting BioShield®75 was shown to be effective against Listeria monocytogenesproducing an average reduction of viable cells by 3.5 log Colony Forming Units (CFU). Salmonella was only killed by 1 log CFU both with and without BioShield®75, proving the compound has very little effect on the bacterium. After completing the trials it appears that BioShield®75 may be useful to prevent Listeria monocytogenes contamination, but it may not be effective against other bacteria.