Main content area

Photocatalytic TiO2 coating of plastic cutting board to prevent microbial cross-contamination

Yemmireddy, Veerachandra K., Hung, Yen-Con
Food control 2017 v.77 pp. 88-95
Escherichia coli O157, antibacterial properties, coatings, cross contamination, cutting boards, foods, light intensity, nanoparticles, oxygen, polyethylene, risk, titanium dioxide, ultraviolet radiation, washing
Kitchen cutting boards are one common source of microbial cross-contamination in foods. In this study, a method was developed to create an antimicrobial coating on HDPE cutting board using UV-activated TiO2 nanoparticles (NPs). The antimicrobial efficacy of the developed coatings was tested against E. coli O157: H7 for 3 h at 0.5 ± 0.05 mW/cm2 UVA light intensity. In addition, the effect of NP loading (0.0125, 0.0625, and 0.125 mg/cm2), and surface treatment of coatings by oxygen plasma for 1–15 min on the bactericidal efficacy was investigated. Further, the bactericidal efficacy of the TiO2 coated cutting board on repeated use (i.e. 1, 2, 3 and 5 times) was also evaluated. The results showed that by increasing the NP loading from 0 to 0.125 mg/cm2 has increased the log reduction from 0.37 to 1.18 CFU/cm2. However, no significant difference (P > 0.05) in the reduction was observed between NP loadings at 0.0625 and 0.125 mg/cm2. Oxygen plasma treatment of the coated surfaces for 5–15 min significantly increased (P ≤ 0.05) the log reduction compared to control sample without plasma treatment. Under the tested conditions, TiO2 coating with 0.0625 mg/cm2 NP loading followed by oxygen plasma treatment for 5 min was found to achieve the greatest reduction up to 2.67 log CFU/cm2. Also, the coated-surfaces were found to retain the original bactericidal property even after up to 5 times washing treatment. The developed TiO2 coating on cutting board showed promise to mitigate the risk of microbial cross-contamination by providing a stable antimicrobial activity for extended use. Plasma treatment further enhanced the bactericidal property of the developed coatings without affecting physical stability.