Red Wine Vinegar Residues as a Sustainable Source of Antioxidant Bacterial Cellulose Materials

Materials made from bacterial cellulose (BC) have attracted considerable attention; however, wider adoption remains constrained by the high cost of conventional culture media. Here, we characterize a preexisting BC byproduct from red wine vinegar fermentation and present a valorization strategy that leverages wine-derived polyphenolics naturally incorporated into the BC network. Film performance was improved through iron-mediated metal−phenolic network formation and incorporation of low molecular weight polyethylene glycol (3.0 wt %) as a plasticizer, yielding biodegradable films with a tensile strength of 9.6 ± 0.5 MPa and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity of 95.4%. Overall, this work demonstrates a practical route to transform a widely available fermentation byproduct into antioxidant BC-based films while advancing circularity in the vinegar industry.