The goals of this study were: (1) to identify the conditions for egg white protein (EWP) film making through extrusion and calendering processes for industry adaptation, and (2) to investigate the current possibilities of the EWP film as a food packaging material by inquiring into the effect of surrounding environment on its properties and by comparing EWP film with PLA. The necessary processing conditions of extrusion and calendering to obtain EWP films were identified and led to transparent (90-94% at 600nm), continuous, and uniform films with a thickness of 110μm. Exposing the films to combinations of temperature (4 or 23°C) and RH (0, 55, or 95%) showed that temperature, RH, and their interactions have significant effect on the properties of EWP films. At 23°C, the film has higher transmittance and lower water and ethanol permeability than at 4°C (p≤0.05). The decrease in RH increases the flexibility and thickness but it decreases the water permeability and transmittance of the films significantly (p≤0.05). The films became more reddish and less yellowish at 55%RH. Neither temperature nor RH had an effect on the tensile strength, first second-order transmission temperature, fungal resistance and lightness of the films. Comparison of EWP films with PLA films shows that both materials have similar optical properties but different tensile and barrier properties. The EWP films reduced the growth of P. pinophilum and A. niger after 48 hours at 100%RH and 23°C. This study proves the feasibility of producing EWP films using the most common filmmaking processing technology and shows that EWP film can be used for specific food packaging applications.
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