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Abstract
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The increasing accumulation of plastic packaging waste and the limited shelf life of fresh-cut produce have created a need for sustainable packaging materials capable of simultaneously reducing environmental impacts and improving preservation of fresh-cut produce. To address this challenge, in this study we formulated biodegradable active films using potato starch (PS) added with potato peel extract (PPE) obtained via sustainable ultrasound-assisted extraction (UAE) with water (pulsed mode: 5 s on/5 s off; 300 W; 30 kHz; 25 min; 45 °C). PPE was incorporated into PS films at concentrations of 2–10% (w/w), and the resulting films were examined for mechanical, physical, optical, barrier, antioxidant and antimicrobial properties. SEM analysis demonstrated smoother, more compact surfaces with higher PPE content, while FTIR confirmed enhanced hydrogen bonding without altering the starch backbone. Films thickness increased from 0.01 ± 0.01 mm (T0) to 0.31 ± 0.01 mm (T5), whereas moisture content, water solubility, and water vapor permeability decreased significantly, indicating improved structural integrity and barrier performance. Color parameters and transparency showed dose-dependent changes due to phenolic compounds, while mechanical strength slightly decreased at higher extract concentrations. Antioxidant activity increased progressively, with TPC reaching 18.71 mg GAE/g, TFC 3.92 mg QE/g, and DPPH scavenging 40.81%. Films exhibited dose-dependent antimicrobial activity against S. aureus (2.09–19.13 mm), E. coli (1.91–31.34 mm), and S. enterica (1.45–21.61 mm). Biodegradability tests showed complete degradation of low-extract containing films by 15 days, while higher PPE containing films degraded nearly completely, contrasting with non-degradable polyethylene controls. Application on fresh-cut potatoes demonstrated that films with higher PPE concentrations (T4–T5) reduced visible browning and delayed spoilage-associated visual changes during 7 days of ambient storage.
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