Effect of Voltage on the Mechanical and Water Resistance Properties of Zein Films by Electrophoretic Deposition

Abstract

The electrophoretic deposition (EPD) technique is widely commercially used in the productions of enormous films and coatings prepared at industrial-scale. In literature, very little information regarding the impact of the voltage on the properties of food-grade protein film is released. In this study, zein film was successfully produced using EPD. The effects of the voltage electrophoretic deposition on the mechanical properties, water resistance features, and microstructures of zein films were investigated. The results indicate that the enhancement of the voltage induced the improvements of tensile strength and elongation of zein film initially and the maximum tensile strength and elongation were achieved at 100 V of the voltage. However, an excessively high voltage could result in the reduction in mechanical properties of zein films. In addition, an increase of the voltage led to the decrease in water vapor permeability (WVP) and water absorption of zein films at the beginning phase. At 100 V, the most hydrophobic film was formed. Compared to the control, SEM results revealed the compact and homogenous structures of zein film using EPD. In conclusion, the findings of this study could potentially facilitate the development of protein-based films using electrophoretic deposition at the optimal voltage with desirable mechanical and water resistance characteristics for food and pharmaceutical packaging purposes.