Utilization of lentil flour as a biopolymer source for the development of edible films

Lentils are one of the cheapest and most nutritional protein sources for vegetarians. Our objective in this study was to evaluate the feasibility of using lentil flour as a raw material for the development of edible films and to investigate the effects of the glycerol concentration (C_g = 1%, 1.5%, and 2%) and process temperature (T_p; 70 and 90 °C) on the physical properties of these films. The films were characterized via their density; water solubility; thermal, morphological, and chemical characteristics; water vapor permeability (WVP); and tensile and optical properties. The lentil flour films were highly transparent and had lower water solubility values yet similar WVPs and mechanical properties compared to most other biodegradable films. An increase in C_g led to the formation of more flexible films with increased hydrophilicity. A T_p of 90 °C resulted in yellower, more transparent films with increased stiffness compared to a T_p of 70 °C. In this study, lentil flour was shown to be an ideal source for edible film production. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46356.