Pumpkin oil cake protein isolate films as potential gas barrier coating

► Pumpkin oil cake protein isolate (PuOC PI) films could be formed in the range of pH, except at pH=4–8. ► The pH of film-forming solutions influenced all examined film’s characteristics. ► The amount of added glycerol significantly affected TS, EB, and film solubility. ► Films prepared with 0.4g glycerol/g PI showed excellent barrier for O2, N2, CO2, and air. ► Obtained films have improved EB and gas permeability characteristics compared to PuOC films. This work was aimed to investigate the potential of PuOC protein isolate (PuOC PI) in preparation of biodegradable films at different pH values (2–12) and plasticizer content (0.3–0.6g glycerol/g PuOC PI). Results showed that films could be formed in a wild range of pH, except at pH=4–8. Films with 0.4 and 0.5g glycerol/g PuOC PI were suitable for further analysis. The pH of film-forming solutions influenced all examined film’s characteristics. The amount of added glycerol significantly affected (p