A novel curdlan/methyl cellulose/walnut green husk polyphenol edible composite film for walnut packaging.

In this study, polyphenols were extracted from walnut green husk, an agricultural waste, and were incorporated into curdlan (CD) and methyl cellulose (MC) to create a novel edible composite film. For structural character, the film matrix was tightly bound primarily by non-covalent bonds and the addition of walnut green husk polyphenols (WGHP) significantly reduced the surface roughness of the composite film. For mechanical properties, the addition of WGHP improve the flexibility of films, and it significantly improved the barrier ability of ultraviolet rays and water-vapor. Furthermore, the incorporation of WGHP to the CD-MC film resulted in enhanced antioxidant and antibacterial effects, which effectively retards lipid oxidation in fried walnuts. Consequently, the fabricated CD-MC-WGHP composite film bears immense potential for use in food preservation applications, particularly in extending the shelf life of fried walnuts. • The polyphenols were extracted from walnut green husk and applied to a new edible composite film. • The addition of WGHP resulted a smooth and uniform film surface. • The incorporation of WGHP could endow the films with strong barrier properties. • WGHP improved the antioxidant and antibacterial activities of films. • The composite film could restrain the deterioration of lipid in fried walnuts. [ABSTRACT FROM AUTHOR]