{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T01:30:38Z","timestamp":1777339838047,"version":"3.51.4"},"reference-count":44,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2024,5,23]],"date-time":"2024-05-23T00:00:00Z","timestamp":1716422400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FEDER funds through the COMPETE 2020 Program and National Funds through FCT\u2014Portuguese Foundation for Science and Technology","award":["LISBOA-01-0247-FEDER-039985\/POCI-01-0247-FEDER-039985"],"award-info":[{"award-number":["LISBOA-01-0247-FEDER-039985\/POCI-01-0247-FEDER-039985"]}]},{"name":"FEDER funds through the COMPETE 2020 Program and National Funds through FCT\u2014Portuguese Foundation for Science and Technology","award":["LA\/P\/0037\/2020"],"award-info":[{"award-number":["LA\/P\/0037\/2020"]}]},{"name":"FEDER funds through the COMPETE 2020 Program and National Funds through FCT\u2014Portuguese Foundation for Science and Technology","award":["UIDP\/50025\/2020"],"award-info":[{"award-number":["UIDP\/50025\/2020"]}]},{"name":"FEDER funds through the COMPETE 2020 Program and National Funds through FCT\u2014Portuguese Foundation for Science and Technology","award":["UIDB\/50025\/2020"],"award-info":[{"award-number":["UIDB\/50025\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Galactomannans are polysaccharides obtained from legume seed extraction. They present a chemical structure consisting of D-mannose chains linked by glycosidic bonds and galactose branches. The main focus lies in their use as thickeners in the food industry, aimed at improving the dielectric properties of food during heating processes within the radiofrequency and microwave ranges. In this work, the prepared galactomannan samples were electrically analyzed through impedance spectroscopy, which is a powerful physical technique. From the experimental measurements, the dielectric permittivity and loss tangent of the galactomannan solutions were analyzed and the electrical modulus formalism was used to study the dielectric relaxations. Crude galactomannans exhibited higher values of permittivity, conductivity, and losses compared to purified galactomannans. Increasing ethanol concentration in galactomannan purification causes an increase in the permittivity and conductivity of galactomannan solutions. In a 1% solution, at 1 kHz, the permittivity increased from 378.56 to 538.09, while in the 2% solution, this increase was from 656.22 to 1103.24. Regarding the conductivity, at the same frequency, the increase was from 1.6 \u00d7 10\u22123 to 3.3 \u00d7 10\u22123 \u03a9\u22121m\u22121 and from 2.9 \u00d7 10\u22123 to 5.5 \u00d7 10\u22123 \u03a9\u22121m\u22121, respectively. The rise of the ethanol concentration in galactomannan purification led to a decrease in the relaxation time, from 448.56 to 159.15 \u03bcs and from 224.81 to 89.50 \u03bcs in the solution with 1 and 2%, respectively. The results suggest that galactomannan from Adenanthera pavonina L. has potential for use in the food industry.<\/jats:p>","DOI":"10.3390\/polym16111476","type":"journal-article","created":{"date-parts":[[2024,5,23]],"date-time":"2024-05-23T05:35:20Z","timestamp":1716442520000},"page":"1476","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Dielectric Characterization of Solutions of Galactomannan Extracted from Adenanthera pavonina L.: Effects of Purification and Ethanol Concentration"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2217-4584","authenticated-orcid":false,"given":"Susana","family":"Devesa","sequence":"first","affiliation":[{"name":"CEMMPRE, ARISE, Department of Mechanical Engineering, University of Coimbra, Rua Lu\u00eds Reis Santos, 3030-788 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6858-9507","authenticated-orcid":false,"given":"Manuel P. F.","family":"Gra\u00e7a","sequence":"additional","affiliation":[{"name":"I3N and Physics Department, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Walajhone O.","family":"Pereira","sequence":"additional","affiliation":[{"name":"Instituto Federal do Maranh\u00e3o (IFMA)\u2014Campus Imperatriz, Imperatriz 65906-335, MA, Brazil"}]},{"given":"Guilherme L.","family":"Santos","sequence":"additional","affiliation":[{"name":"Instituto Federal do Maranh\u00e3o (IFMA)\u2014Campus Imperatriz, Imperatriz 65906-335, MA, Brazil"}]},{"given":"Jo\u00e3o F.","family":"da Silva Neto","sequence":"additional","affiliation":[{"name":"Instituto Federal do Maranh\u00e3o (IFMA)\u2014Campus Imperatriz, Imperatriz 65906-335, MA, Brazil"}]},{"given":"Filipe M. B.","family":"Amaral","sequence":"additional","affiliation":[{"name":"I3N and Physics Department, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"Polytechnic Institute of Coimbra, Coimbra Health School (ESTeSC), 3046-854 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9007-2221","authenticated-orcid":false,"given":"Imen","family":"Hammami","sequence":"additional","affiliation":[{"name":"I3N and Physics Department, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5205-8939","authenticated-orcid":false,"given":"Fernando","family":"Mendes","sequence":"additional","affiliation":[{"name":"Polytechnic University of Coimbra, ESTESC, UCPCBL, 3046-854 Coimbra, Portugal"},{"name":"H&TRC\u2014Health and Technology Research Center, Coimbra Health School, Polytechnic University of Coimbra, 3046-854 Coimbra, Portugal"},{"name":"Biophysics Institute of Faculty of Medicine, Coimbra Institute for Clinical and Biomedical Research (iCBR) Area of Environment Genetics and Oncobiology (CIMAGO), University of Coimbra, 3000-548 Coimbra, Portugal"},{"name":"Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3000-548 Coimbra, Portugal"},{"name":"Clinical Academic Center of Coimbra, Coimbra, Portugal, Polytechnic University of Coimbra, ESTESC, UCPNS, SM Bispo, 3045-093 Coimbra, Portugal"},{"name":"European Association for Professions in Biomedical Sciences, 1000 Brussels, Belgium"}]},{"given":"Ana A. M.","family":"Mac\u00eado","sequence":"additional","affiliation":[{"name":"Instituto Federal do Maranh\u00e3o (IFMA)\u2014Campus Imperatriz, Imperatriz 65906-335, MA, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"384","DOI":"10.1016\/j.ijrefrig.2020.06.029","article-title":"In-Situ Dielectric Analysis on the Responses of Vegetable Cells to Freezing Treatment","volume":"118","author":"Zhang","year":"2020","journal-title":"Int. J. Refrig."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1016\/j.jfoodeng.2015.08.008","article-title":"Dielectric Properties of Dried Vegetable Powders and Their Temperature Profile during Radio Frequency Heating","volume":"169","author":"Ozturk","year":"2016","journal-title":"J. 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