{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T10:36:57Z","timestamp":1773916617308,"version":"3.50.1"},"reference-count":36,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T00:00:00Z","timestamp":1773705600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Funds by FCT\u2014Portuguese Foundation for Science and Technology","award":["UID\/04033\/2025"],"award-info":[{"award-number":["UID\/04033\/2025"]}]},{"name":"National Funds by FCT\u2014Portuguese Foundation for Science and Technology","award":["LA\/P\/0126\/2020"],"award-info":[{"award-number":["LA\/P\/0126\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The authentication of wines with Protected Designation of Origin (PDO) status is a key requirement for quality assurance, traceability, and consumer trust, particularly in traditional wine-producing regions such as the Douro Demarcated Region (Portugal). Among the certification criteria, the reliable identification of grape varieties remains technically challenging, especially when rapid and non-destructive analytical approaches are required. In this study, Fourier-transform infrared spectroscopy coupled with chemometric analysis was evaluated as a rapid screening approach for the differentiation of monovarietal Douro wines produced under standardized microvinification conditions. Twenty-one monovarietal wines were analyzed using mid-infrared spectra (1800\u20131000 cm\u22121) and classification models were developed using Partial Least Squares Discriminant Analysis (PLS-DA). The PLS-DA models showed preliminary discriminatory capacity, with apparent error rates of 10.2% for calibration and 19.3% under leave-one-out cross-validation. The results indicate that FTIR-ATR spectroscopy combined with chemometrics captures chemically relevant spectral variability associated with grape varietal differences and shows potential as a rapid exploratory screening approach within PDO traceability frameworks. Although the study is based on a limited number of biological replicates from a single vintage and sub-region, the findings provide a methodological baseline for future multi-vintage and multi-region investigations aimed at consolidating FTIR-based approaches for varietal authentication of Douro wines.<\/jats:p>","DOI":"10.3390\/molecules31061004","type":"journal-article","created":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T09:35:57Z","timestamp":1773740157000},"page":"1004","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["FTIR-ATR Spectroscopy and Chemometrics for Varietal Screening of PDO Douro Monovarietal Wines: An Exploratory Feasibility Study"],"prefix":"10.3390","volume":"31","author":[{"given":"\u00c2ngela","family":"Vieira","sequence":"first","affiliation":[{"name":"Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), Institute for Innovation, Capacity Building, and Sustainability of Agri-Food Production (Inov4Agro), Universidade de Tr\u00e1s-os-Montes e Alto Douro (UTAD), 5000-801 Vila Real, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3445-5479","authenticated-orcid":false,"given":"Amanda Priscila Silva","family":"Nascimento","sequence":"additional","affiliation":[{"name":"Academic Unit of Food Engineering, Federal University of Campina Grande (UFCG), Apr\u00edgio Veloso Avenue, 882, Campina Grande 58429-900, PB, Brazil"},{"name":"SENAI Institute of Technology for Operational Efficiency (IST EO), Federation of Industries of the State of Para\u00edba (FIEPB), Campina Grande 58429-900, PB, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-0816-0745","authenticated-orcid":false,"given":"Maria Z\u00e9lia","family":"Branco","sequence":"additional","affiliation":[{"name":"Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), Institute for Innovation, Capacity Building, and Sustainability of Agri-Food Production (Inov4Agro), Universidade de Tr\u00e1s-os-Montes e Alto Douro (UTAD), 5000-801 Vila Real, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8229-0117","authenticated-orcid":false,"given":"Paula","family":"Martins-Lopes","sequence":"additional","affiliation":[{"name":"Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), Institute for Innovation, Capacity Building, and Sustainability of Agri-Food Production (Inov4Agro), Universidade de Tr\u00e1s-os-Montes e Alto Douro (UTAD), 5000-801 Vila Real, Portugal"}]},{"given":"Jos\u00e9 Eduardo","family":"Eiras-Dias","sequence":"additional","affiliation":[{"name":"National Institute for Agricultural and Veterinary Research (INIAV), 2565-191 Dois Portos, Portugal"}]},{"given":"Jo\u00e3o","family":"Braz\u00e3o","sequence":"additional","affiliation":[{"name":"National Institute for Agricultural and Veterinary Research (INIAV), 2565-191 Dois Portos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3341-861X","authenticated-orcid":false,"given":"Lu\u00eds","family":"Ferreira","sequence":"additional","affiliation":[{"name":"Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), Institute for Innovation, Capacity Building, and Sustainability of Agri-Food Production (Inov4Agro), Universidade de Tr\u00e1s-os-Montes e Alto Douro (UTAD), 5000-801 Vila Real, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0380-0399","authenticated-orcid":false,"given":"Nelson","family":"Machado","sequence":"additional","affiliation":[{"name":"Institute for Systems and Computer Engineering, Technology and Science (INESC TEC), Faculty of Engineering, University of Porto (FEUP), 4200-465 Porto, Portugal"},{"name":"NESC TEC Campus da Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5834-6141","authenticated-orcid":false,"given":"Ana Novo","family":"Barros","sequence":"additional","affiliation":[{"name":"Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), Institute for Innovation, Capacity Building, and Sustainability of Agri-Food Production (Inov4Agro), Universidade de Tr\u00e1s-os-Montes e Alto Douro (UTAD), 5000-801 Vila Real, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ohana-Levi, N., and Netzer, Y. 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