{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T14:34:08Z","timestamp":1776177248180,"version":"3.50.1"},"reference-count":60,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2020,6,2]],"date-time":"2020-06-02T00:00:00Z","timestamp":1591056000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT - Foundation for Science and Technology","award":["UIDB\/05183\/2020"],"award-info":[{"award-number":["UIDB\/05183\/2020"]}]},{"name":"FCT - Foundation for Science and Technology","award":["UIDB\/05183\/2020"],"award-info":[{"award-number":["UIDB\/05183\/2020"]}]},{"name":"Project CENTRO-04-3928-FEDER 0000281 \u201cValidation of a new ageing technology for wine spirit from Lourinh\u00e3","award":["CENTRO-04-3928-FEDER 0000281"],"award-info":[{"award-number":["CENTRO-04-3928-FEDER 0000281"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Mathematics"],"abstract":"<jats:p>Fourier transform infrared spectroscopy (FTIR) with Attenuated Total Reflection (ATR) combined with functional data analysis (FDA) was applied to differentiate aged wine spirits according to the ageing technology (traditional using 250 L wooden barrels versus alternative using micro-oxygenation and wood staves applied in 1000 L stainless steel tanks), the wood species used (chestnut and oak), and the ageing time (6, 12, and 18 months). For this purpose, several features of the wine spirits were examined: chromatic characteristics resulting from the CIELab method, total phenolic index, concentrations of furfural, ellagic acid, vanillin, and coniferaldehyde, and total content of low molecular weight phenolic compounds determined by HPLC. FDA applied to spectral data highlighted the differentiation between all groups of samples, confirming the differentiation observed with the analytical parameters measured. All samples in the test set were differentiated and correctly assigned to the aged wine spirits by FDA. The FTIR-ATR spectroscopy combined with FDA is a powerful methodology to discriminate wine spirits resulting from different ageing technologies.<\/jats:p>","DOI":"10.3390\/math8060896","type":"journal-article","created":{"date-parts":[[2020,6,3]],"date-time":"2020-06-03T04:12:09Z","timestamp":1591157529000},"page":"896","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Application of Functional Data Analysis and FTIR-ATR Spectroscopy to Discriminate Wine Spirits Ageing Technologies"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0267-3252","authenticated-orcid":false,"given":"Of\u00e9lia","family":"Anjos","sequence":"first","affiliation":[{"name":"Instituto Polit\u00e9cnico de Castelo Branco, Escola Superior Agr\u00e1ria, 6001-909 Castelo Branco, Portugal"},{"name":"CEF, Instituto Superior de Agronomia, Universidade de Lisboa, 1349-017 Lisboa, Portugal"},{"name":"CBPBI, Centro de Biotecnologia de Plantas da Beira Interior, 6001-909 Castelo Branco, Portugal"}]},{"given":"Miguel","family":"Mart\u00ednez Comesa\u00f1a","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Heat Engines and Fluid Mechanics, Industrial Engineering School, University of Vigo, Maxwell s\/n, 36310 Vigo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2151-2008","authenticated-orcid":false,"given":"Ilda","family":"Caldeira","sequence":"additional","affiliation":[{"name":"INIAV, INIAV-Dois Portos, Quinta da Almo\u00ednha, 2565-191 Dois Portos, Portugal"},{"name":"MED\u2014MediterraneanInstitute for Agriculture, Environment and Development, Instituto de forma\u00e7\u00e3o avan\u00e7ada, Universidade de \u00c9vora, P\u00f3lo da Mitra, Ap. 94, 7006-554 \u00c9vora, Portugal"}]},{"given":"Soraia In\u00eas","family":"Pedro","sequence":"additional","affiliation":[{"name":"Instituto Polit\u00e9cnico de Castelo Branco, Escola Superior Agr\u00e1ria, 6001-909 Castelo Branco, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8616-9509","authenticated-orcid":false,"given":"Pablo","family":"Egu\u00eda Oller","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Heat Engines and Fluid Mechanics, Industrial Engineering School, University of Vigo, Maxwell s\/n, 36310 Vigo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9781-6481","authenticated-orcid":false,"given":"Sara","family":"Canas","sequence":"additional","affiliation":[{"name":"INIAV, INIAV-Dois Portos, Quinta da Almo\u00ednha, 2565-191 Dois Portos, Portugal"},{"name":"MED\u2014MediterraneanInstitute for Agriculture, Environment and Development, Instituto de forma\u00e7\u00e3o avan\u00e7ada, Universidade de \u00c9vora, P\u00f3lo da Mitra, Ap. 94, 7006-554 \u00c9vora, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Canas, S. 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