Cellulose‐Reinforced Banana Starch Edible Films Incorporating Quercetin Nanoemulsions: Structure–Property Relationships, Antioxidant Activity, and Simulated Gastrointestinal Release

ABSTRACT Biodegradable active films were developed using banana starch reinforced with nanocellulose and functionalized with quercetin‐loaded nanoemulsions (QNE). The films were prepared by casting and evaluated for mechanical, barrier, optical, antioxidant, and gastrointestinal release properties. QNE incorporation reduced tensile strength (from 26.3 to 9.4 MPa) while increasing elongation at break (from 12.3% to 78.2%), indicating a plasticizing effect. Water vapor permeability and solubility decreased with QNE addition, reflecting enhanced moisture resistance. Optical properties were altered, with reduced luminosity and increased yellow color intensity due to quercetin presence. Moisture sorption studies showed decreased monolayer water content and increased sorption energy, indicating reduced water affinity. DPPH assays confirmed that antioxidant activity was maintained after film formation, reaching up to 75.2% in the highest‐QNE formulation. In vitro digestion studies showed limited quercetin release in gastric fluid but a marked increase in intestinal conditions, suggesting effective protection and targeted release. These findings demonstrate the potential of QNE‐loaded starch films as edible packaging materials with improved flexibility, water resistance, antioxidant capacity, and controlled polyphenol delivery.