Antibacterial effectiveness of laser surface textured metal on meat-borne bacteria

Abstract

This study evaluated the potential of using laser-textured metal surfaces (etched coupons) designed and manufactured using an ultrafast laser to prevent bacterial attachment. The etched and unetched surfaces were compared for bacterial attachment against Escherichia coli AGR5151 and Brochothrix thermosphacta NZRM 3320 at high (∼8 Log colony-forming unit (CFU)/coupon) and low (∼5 Log CFU/coupon) inoculum levels. For B. thermosphacta, one out of the five etched surfaces showed significantly (p < 0.05) lower attachment by 0.2–1.3 Log CFU/coupon using the high inoculum, whereas four out of five etched surfaces exhibited significantly (p < 0.05) reduced attachment compared to the control with the lower inoculum. Similarly, for E. coli, three surfaces demonstrated significantly (p < 0.05) lower attachment by 0.7–1.2 Log CFU/coupon with the high inoculum and four surfaces showed lower attachment by 0.1–1.4 Log CFU/coupon compared to the control with the lower inoculum. Only one type of etched surface/coupon was common in its ability to reduce attachment for both the bacteria tested. It can be concluded that the bacterial strain being targeted can be one of the major factors that determine the efficacy of these surfaces to inhibit attachment. The findings also suggest a potential link between effectiveness and surface characteristics like roughness and wettability.