Abstract #T140

# T140
The effect of xenon pulsed-light technology on biofilm adhered to stainless steel surfaces.
Stephanie Jacquez*1, Rafael Jimenez-Flores1, 1California Polytechnic State University, San Luis Obispo, CA.

In food processing, inadequate sanitation procedures lead to the formation of biofilms, in which bacteria attach to surfaces and aggregate in a hydrated polymeric matrix of their own synthesis. Formation of these sessile communities and their inherent resistance to existing sanitation agents are at the root of the risk of bacterial infections for consumers. Based on this evidence, an effective method for reducing biofilm formation in dairy processing equipment is necessary. UV pulsed light technology has proven effective in eliminating microorganism populations on food products. The objective of this work is to evaluate the effect of pulsed light technology on a biofilm consisting of different dairy media (e.g., whey protein concentrate (WPC) and pure lactose) as well as 3 strains of spore forming Bacillus species (B. subtilis, B. coagulans, and B. licheniformis) adhered to square, 2.5 × 2.5, ASI 304, stainless steel coupons . Four treatment levels (no treatment, 5 bursts, 10 s, and 20 s) were applied to the coupon surfaces using the Xenon model RC847 machine. Each coupon was placed at a distance of 10.5 cm away from the UV lamp. The pulsed light effect was evaluated using the pour plate technique with 0.2% (w/v) starch TSA and incubated for 48h at 55 C. The adhesion of Bacillus to stainless steel in water as matrix was 1000 to 3000/cm2 as measured in our laboratory. When compared with the No treatment group, there was a maximum of a 3.96 delta log kill rate in the biofilm created with whey protein concentrate when exposed to 20 s of pulsed UV light. Results indicate a difference between kill rates at 20 s with biofilms created with 5% whey protein concentrate and 5% lactose.