Extrusion-Blown PBAT/Thermoplastic Starch (TPS) Active Films Incorporated with Grape Seed Extract for Extending the Shelf Life of Peanut Butter

In this study, poly(butylene adipate-co-terephthalate) (PBAT), starch, glycerol, and grape seed extract (GSE) were blended and extruded to fabricate PBAT/thermoplastic starch(TPS)/GSE active films by blow molding. The interaction between GSE and TPS primarily occurred through hydrogen bonding, with little interaction observed with PBAT. The oxygen barrier property of the film was improved by the incorporation of GSE into the films, whereas the mechanical properties slightly decreased. The PBAT/TPS/GSE films had excellent UV blocking properties imparted by PBAT and visible light blocking properties endowed by GSE. The films containing GSE offered antimicrobial activity against <i>Escherichia coli</i> and <i>Staphylococcus aureus</i> by delaying bacterial growth. Also, the GSE-added films exhibited antioxidant activity with strong dose dependence due to the free radical scavenging ability of polyphenolic compounds in GSE. The shelf life of peanut butter packaged with the PBAT/TPS/GSE-5 film was expected to exceed 300 days, which was approximately twice that of LDPE film packaging. The proposed active films had good material properties, functional activities, and excellent ability to prolong the shelf life of peanut butter.