Mechanical, Chemical, Physical and Antimicrobial Properties of Chitosan-Based Film Incorporated With Walnut Septum

Chitosan films incorporated with various concentrations of raw walnut septum powder wereprepared and investigated for the production of biodegradable plastics, especially in packaging to improvethe quality, delay the spoilage of packaged food, as well as increase the safety and shelf life of food. Walnutseptum ultrafine powder was produced with the following steps selecting raw materials, cleaning, drying,freezing, and rapidly placing the frozen walnut septum in a crusher and then crushing and screening thewalnut septum powder. So as to obtained the walnut septum (WNS) ultrafine powder having crushinggranularity being ۳۰۰ meshes.In the present study, the efficacy of response surface models was analysed to optimize experimentalconditions for maximum improve of film thickness (FT), Tensile strength (TS), elongation at break (EB)water vapor permeability (WVP) and oxygen permeability (OP).۲The estimated overall optimum conditions by overlaying the responses of BoxBehnken design of responsesurface methodology were found to be FT=۰.۰۹۷±۰.۰۰۵ (chitosan without WNS= ۰.۱۰۱±۰.۰۶)TS=۲۹.۵۸۱±۰.۳۸۱ (۱۳.۸۷۱±۰.۶۳۱), EB=۳۴.۱۲±۲.۱۵ (۳۱.۹۷±۱.۳۳), WVP=۲.۱۱±۰.۰۵ (۲.۶۶±۰.۰۳)×۱۰-۱۰ andOP=۰.۴۸±۰.۰۵ (۱.۴۱±۰.۰۴)×۱۰-۱۸In optimum condition, chitosan films incorporated with WNS showed the strongest antimicrobial activityand was significantly increased in tensile strength (TS) of film and decreased water vapor permeability andoxygen permeability. Microstructure of the film incorporated with WNS was investigated by Fouriertransform infrared spectroscopy and scanning electron microscopy (SEM) and it was Found WNS wasdispersed homogenously into chitosan matrix. Surface morphology of the film with WNS revealed ahomogeneous structure. Overall, chitosan films with WNS could be used as novel food packaging materialdue to their excellent antimicrobial and mechanical properties