Background: Although surface characteristics of food contact materials are known to alter the efficacy of cleaning procedures there is a lack of data establishing how cleaning/sanitization practices affect the surface characteristics of materials used for produce handling on-farm. The overall objective of this work was to characterize the effects of cleaning and sanitization procedures on the surface properties of new and extended-wear polyethylene bins used for produce harvest and handling.
Results: Compared to detergent cleaned samples, chlorine and quaternary ammonium sanitization resulted in a decrease in advancing contact angle from 100° to 88° and 59°, respectively, after 2 min exposure. However, changes in surface chemistry were not observed. Increasing sanitization time to 144 min (representative of 4320 sanitization cycles) resulted in an increase in contact angle to 73° for quaternary ammonium sanitization and a decrease in contact angle to 75° for chlorine sanitization. Abrasion increased contact angle hysteresis due to enhanced surface roughness. The hysteresis effect of abraded material was reduced with quaternary ammonium treatment.
Conclusions: This work indicates that sanitizing agents employed in on-farm cleaning can alter the surface characteristics of polyethylene picking bins and should be considered in developing cleaning and sanitization procedures.
Keywords: abrasion; bins; cleaning; produce; sanitization; tomato.
© 2013 Society of Chemical Industry.