{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T17:00:58Z","timestamp":1790182858539,"version":"4.1.0"},"reference-count":88,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,8,24]],"date-time":"2025-08-24T00:00:00Z","timestamp":1755993600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>Due to the prevalence of plastic-packaged foods, as well as the need for real-time food monitoring by consumers, reducing plastic pollution is essential for a healthier environment and nutrition. For these reasons, in this work, biodegradable pH-responsive chitosan films enriched with wine lees-derived anthocyanins were produced, and their pH sensitivity was thoroughly evaluated. Optimization of ultrasound-assisted extraction using ethanol\/water mixtures as conventional solvents was conducted and the optimal conditions (regarding total anthocyanin content, total phenolic content, and antioxidant activity) were used to perform a screening of extraction with 16 different Natural Deep Eutectic Solvents. Among them, choline chloride: butylene glycol (1:4), at a concentration of 50% v\/v in water, demonstrated the highest anthocyanin recovery and was selected for the preparation of the films. The resulting films exhibited an excellent colorimetric response to pH changes, with a color difference (\u0394E) exceeding 6.8 at all tested pH values, improved mechanical properties, nearly zero UV permeability, and their antioxidant activity increased by up to 6.1-fold compared to pure chitosan film. Finally, the film was applied in detecting the freshness of pork meat, exhibiting a \u0394E of 15.3. The results demonstrate that the developed film is a promising alternative for intelligent, bioactive, and biodegradable food packaging for food applications.<\/jats:p>","DOI":"10.3390\/gels11090676","type":"journal-article","created":{"date-parts":[[2025,8,25]],"date-time":"2025-08-25T00:09:53Z","timestamp":1756080593000},"page":"676","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["pH-Responsive Chitosan Films Enriched with NADES-Extracted Wine Lees Anthocyanins for In Situ Food Monitoring"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3135-8470","authenticated-orcid":false,"given":"Panagiotis E.","family":"Athanasiou","sequence":"first","affiliation":[{"name":"Laboratory of Biotechnology, Department of Biological Applications and Technology, University of Ioannina, 45110 Ioannina, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1051-9001","authenticated-orcid":false,"given":"Michaela","family":"Patila","sequence":"additional","affiliation":[{"name":"Laboratory of Biotechnology, Department of Biological Applications and Technology, University of Ioannina, 45110 Ioannina, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3958-6830","authenticated-orcid":false,"given":"Renia","family":"Fotiadou","sequence":"additional","affiliation":[{"name":"Laboratory of Biotechnology, Department of Biological Applications and Technology, University of Ioannina, 45110 Ioannina, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Iro","family":"Giotopoulou","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, University of Ioannina, 45110 Ioannina, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0917-3920","authenticated-orcid":false,"given":"Nektaria-Marianthi","family":"Barkoula","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, University of Ioannina, 45110 Ioannina, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9393-6267","authenticated-orcid":false,"given":"Epaminondas","family":"Voutsas","sequence":"additional","affiliation":[{"name":"Laboratory of Thermodynamics and Transport Phenomena, School of Chemical Engineering, National Technical University of Athens, Zografou Campus, 15780 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8196-4885","authenticated-orcid":false,"given":"Haralambos","family":"Stamatis","sequence":"additional","affiliation":[{"name":"Laboratory of Biotechnology, Department of Biological Applications and Technology, University of Ioannina, 45110 Ioannina, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1016\/j.tifs.2020.08.014","article-title":"PH-Sensitive (Halochromic) Smart Packaging Films Based on Natural Food Colorants for the Monitoring of Food Quality and Safety","volume":"105","author":"Mohammadian","year":"2020","journal-title":"Trends Food Sci. 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