{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T22:19:12Z","timestamp":1774045152766,"version":"3.50.1"},"reference-count":44,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2024,9,26]],"date-time":"2024-09-26T00:00:00Z","timestamp":1727308800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Funds from FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","award":["UIDB\/50016\/2020"],"award-info":[{"award-number":["UIDB\/50016\/2020"]}]},{"name":"National Funds from FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","award":["619864-EPP-1-2020-1-BE-EPPKA1-JMD-MOB"],"award-info":[{"award-number":["619864-EPP-1-2020-1-BE-EPPKA1-JMD-MOB"]}]},{"name":"National Funds from FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","award":["UI\/BD\/152825\/2022"],"award-info":[{"award-number":["UI\/BD\/152825\/2022"]}]},{"name":"European Master of Science in Sustainable Food Systems Engineering, Technology and Business","award":["UIDB\/50016\/2020"],"award-info":[{"award-number":["UIDB\/50016\/2020"]}]},{"name":"European Master of Science in Sustainable Food Systems Engineering, Technology and Business","award":["619864-EPP-1-2020-1-BE-EPPKA1-JMD-MOB"],"award-info":[{"award-number":["619864-EPP-1-2020-1-BE-EPPKA1-JMD-MOB"]}]},{"name":"European Master of Science in Sustainable Food Systems Engineering, Technology and Business","award":["UI\/BD\/152825\/2022"],"award-info":[{"award-number":["UI\/BD\/152825\/2022"]}]},{"name":"Portuguese government","award":["UIDB\/50016\/2020"],"award-info":[{"award-number":["UIDB\/50016\/2020"]}]},{"name":"Portuguese government","award":["619864-EPP-1-2020-1-BE-EPPKA1-JMD-MOB"],"award-info":[{"award-number":["619864-EPP-1-2020-1-BE-EPPKA1-JMD-MOB"]}]},{"name":"Portuguese government","award":["UI\/BD\/152825\/2022"],"award-info":[{"award-number":["UI\/BD\/152825\/2022"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Processes"],"abstract":"<jats:p>Apple and ginger mixed pomace is a by-product that can be valorized by drying. In this study, mixed pomace was subjected to hot-air drying (HAD) at 45, 62, and 70 \u00b0C and stepwise at 45 \u00b0C followed by at 62 \u00b0C or the reverse, at 62 \u00b0C followed by at 45 \u00b0C (2.5 mm layer), and microwave drying (MWD) at 100, 180, and 300 W (2.5 mm and 1.5 mm layers) and stepwise at 100 W followed by at 300 W (2.5 mm layer). The results show that the Crank model well fitted the HAD kinetics, with a water effective diffusivity (Deff) of 2.28 \u00b1 0.06 \u00d7 10\u221210\u20134.83 \u00b1 0.16 \u00d7 10\u221210 m2\/s and energy of activation of 23.9 kJ\/mol. The step approach of drying at 45 \u00b0C followed by at 62 \u00b0C resulted in a higher Deff than the reverse approach (drying at 62 \u00b0C followed by at 45 \u00b0C). The Midilli et al. model presented a good fit for the MWD kinetics. The drying time was calculated using these models to achieve 12% moisture content in the pomace and found to be 125.0 \u00b1 9.2\u2013439.5 \u00b1 118.2 min for HAD, and 11.1 \u00b1 0.2\u201361.5 \u00b1 6.0 min for MWD. The specific energy required was 410.78 \u00b1 6.30\u2013763.79 \u00b1 205.4 kWh\/kg and 1.32 \u00b1 0.01\u20132.26 \u00b1 0.05 kWh\/kg, respectively. MWD at 180 W preserved the total phenolic content and the antioxidant activity (ABTS, DPPH) better than HAD at 62 \u00b0C. The former technology also preserved the pomace color well, with a low color difference, \u0394E, of 7.39 \u00b1 1.1. Therefore, MWD is more promising than HAD to dry apple and ginger pomace, reducing the environmental impact of the drying process due to its lower energy consumption, shorter drying time, and better quality. The dried product could be converted into apple and ginger pomace flour to be used as a novel food ingredient.<\/jats:p>","DOI":"10.3390\/pr12102096","type":"journal-article","created":{"date-parts":[[2024,9,26]],"date-time":"2024-09-26T11:40:27Z","timestamp":1727350827000},"page":"2096","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["A Comparative Study of Drying Technologies for Apple and Ginger Pomace: Kinetic Modeling and Antioxidant Properties"],"prefix":"10.3390","volume":"12","author":[{"given":"Beatriz Z. R.","family":"Araujo","sequence":"first","affiliation":[{"name":"CBQF\u2014Centro de Biotecnologia e Qu\u00edmica Fina\u2014Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5611-0263","authenticated-orcid":false,"given":"Valter F. R.","family":"Martins","sequence":"additional","affiliation":[{"name":"CBQF\u2014Centro de Biotecnologia e Qu\u00edmica Fina\u2014Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0760-3184","authenticated-orcid":false,"given":"Manuela E.","family":"Pintado","sequence":"additional","affiliation":[{"name":"CBQF\u2014Centro de Biotecnologia e Qu\u00edmica Fina\u2014Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5138-6941","authenticated-orcid":false,"given":"Rui M. S. C.","family":"Morais","sequence":"additional","affiliation":[{"name":"CBQF\u2014Centro de Biotecnologia e Qu\u00edmica Fina\u2014Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1059-9649","authenticated-orcid":false,"given":"Alcina M. M. B.","family":"Morais","sequence":"additional","affiliation":[{"name":"CBQF\u2014Centro de Biotecnologia e Qu\u00edmica Fina\u2014Laborat\u00f3rio Associado, Escola Superior de Biotecnologia, Universidade Cat\u00f3lica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"98","DOI":"10.1016\/j.wasman.2018.04.038","article-title":"Environmental impacts of food waste in Europe","volume":"77","author":"Scherhaufer","year":"2018","journal-title":"Waste Manag."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"285","DOI":"10.1080\/07388550802368895","article-title":"Processing of apple pomace for bioactive molecules","volume":"28","author":"Bhushan","year":"2008","journal-title":"Crit. Rev. Biotechnol."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Gumul, D., Kruczek, M., Ivani\u0161ov\u00e1, E., S\u0142upski, J., and Kowalski, S. (2023). Apple pomace as an ingredient enriching wheat pasta with health-promoting compounds. Foods, 12.","DOI":"10.3390\/foods12040804"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"e13098","DOI":"10.1111\/jfpp.13098","article-title":"Utilization of apple pomace in the preparation of fiber-enriched acidophilus yoghurt","volume":"41","author":"Issar","year":"2017","journal-title":"J. Food Proc. Preserv."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Jovanovi\u0107, M., Petrovi\u0107, M., Mio\u010dinovi\u0107, J., Zlatanovi\u0107, S., Lali\u010di\u0107 Petronijevi\u0107, J., Miti\u0107-\u0106ulafi\u0107, D., and Gorjanovi\u0107, S. (2020). Bioactivity and sensory properties of probiotic yogurt fortified with apple pomace flour. Foods, 9.","DOI":"10.3390\/foods9060763"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"109220","DOI":"10.1016\/j.lwt.2020.109220","article-title":"Modification of insoluble dietary fiber from ginger residue through enzymatic treatments to improve its bioactive properties","volume":"125","author":"Wang","year":"2020","journal-title":"LWT"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2772","DOI":"10.1080\/10942912.2023.2254014","article-title":"Bio valorization and industrial applications of ginger waste: A review","volume":"26","author":"Gulzar","year":"2023","journal-title":"Int. J. Food Prop."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Lyu, F., Luiz, S.F., Azeredo, D.R.P., Cruz, A.G., Ajlouni, S., and Ranadheera, C.S. (2020). Apple pomace as a functional and healthy ingredient in food products: A review. Processes, 8.","DOI":"10.3390\/pr8030319"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1016\/j.cep.2014.05.006","article-title":"Convective-intermittent drying of cherries preceded by ultrasonic assisted osmotic dehydration","volume":"82","author":"Kowalski","year":"2014","journal-title":"Chem. Eng. Proc."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1007\/s12393-012-9048-x","article-title":"Microwave drying of food and agricultural materials: Basics and heat and mass transfer modelling","volume":"4","author":"Feng","year":"2012","journal-title":"Food Eng. Rev."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"427","DOI":"10.1021\/ie50137a021","article-title":"The Rate of Drying of Solid Materials","volume":"13","author":"Lewis","year":"1921","journal-title":"J. Ind. Eng. Chem."},{"key":"ref_12","first-page":"169","article-title":"Grain drying theory. II. Temperature effects on drying coefficients","volume":"6","author":"Henderson","year":"1961","journal-title":"J. Agric. Eng. Res."},{"key":"ref_13","unstructured":"Crank, J. (1975). The Mathematics of Diffusion, Clarendon Press. [2nd ed.]."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1503","DOI":"10.1081\/DRT-120005864","article-title":"A new model for single-layer drying","volume":"20","author":"Midilli","year":"2002","journal-title":"Dry. Technol."},{"key":"ref_15","unstructured":"A.O.A.C (2005). Official Methods of Analysis, Association of the Official Analytical Chemists. [18th ed.]. Method A.O.A.C. 930.15;."},{"key":"ref_16","unstructured":"Slack, P.T. (1997). Analytical Methods Manual, Leatherhead Food R.A.. [3rd ed.]. Issue 2."},{"key":"ref_17","unstructured":"(2009). Food and Feed Products\u2014General Guidelines for the Determination of Nitrogen by the Kjeldahl Method (Standard No. ISO 1871:2009)."},{"key":"ref_18","unstructured":"A.O.A.C (2003). Official Methods of Analysis, Association of the Official Analytical Chemists. Method A.O.A.C. 991.43;."},{"key":"ref_19","unstructured":"A.O.A.C (2000). Official Methods of Analysis, Association of the Official Analytical Chemists. Method A.O.A.C. 985.29;."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"455","DOI":"10.1016\/j.jfoodeng.2004.06.023","article-title":"Modeling of olive cake thin-layer drying process","volume":"68","author":"Akgun","year":"2005","journal-title":"J. Food Eng."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Popescu, M., Iancu, P., Plesu, V., Bildea, C.S., and Manolache, F.A. (2023). Mathematical Modeling of Thin-Layer Drying Kinetics of Tomato Peels: Influence of Drying Temperature on the Energy Requirements and Extracts Quality. Foods, 12.","DOI":"10.3390\/foods12203883"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1192","DOI":"10.1016\/j.enconman.2010.09.014","article-title":"Evaluation of energy consumption in different drying methods","volume":"52","author":"Motevali","year":"2011","journal-title":"Energy Convers. Manag."},{"key":"ref_23","unstructured":"Commission Internationale de L\u2019Eclairage, C.I.E. (1978). Recommendations on Uniform Color Spaces, Color-Difference Equations, Psychometric Color Terms, C.I.E.. TC 1."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Martins, V.F.R., Ribeiro, T.B., Lopes, A.I., Pintado, M.E., Morais, R.M.S.C., and Morais, A.M.B. (2024). Comparison among Different Green Extraction Methods of Polyphenolic Compounds from Exhausted Olive Oil Pomace and the Bioactivity of the Extracts. Molecules, 29.","DOI":"10.3390\/molecules29091935"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2977","DOI":"10.1111\/1750-3841.15449","article-title":"Apple pomace as food fortification ingredient: A systematic review and meta-analysis","volume":"85","author":"Antonic","year":"2020","journal-title":"J. Food Sci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1016\/S0260-8774(03)00136-5","article-title":"Drying constant: Literature data compilation for foodstuffs","volume":"61","author":"Krokida","year":"2004","journal-title":"J. Food Eng."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Xu, X., Zhao, T., Ma, J., Song, Q., Wei, Q., and Sun, W. (2022). Application of two-stage variable temperature drying in hot air-drying of paddy rice. Foods, 11.","DOI":"10.3390\/foods11060888"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Mujumdar, A.S. (2006). Handbook of Industrial Drying, CRC Press. [3rd ed.].","DOI":"10.1201\/9781420017618"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1016\/S0260-8774(03)00144-4","article-title":"Modeling shrinkage during convective drying of food materials: A review","volume":"61","author":"Mayor","year":"2004","journal-title":"J. Food Eng."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1559","DOI":"10.1081\/DRT-120014052","article-title":"On the study of time-varying temperature drying\u2014Effect on drying kinetics and product quality","volume":"20","author":"Chua","year":"2002","journal-title":"Dry. Technol."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Tulej, W., and G\u0142owacki, S. (2022). Modeling of the Drying Process of Apple Pomace. Appl. Sci., 12.","DOI":"10.3390\/app12031434"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"983","DOI":"10.1007\/s00231-014-1470-6","article-title":"Effective moisture diffusivity determination and mathematical modelling of drying curves of apple pomace","volume":"51","author":"Kara","year":"2015","journal-title":"Heat Mass Transf."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Majumder, P., Sinha, A., Mishra, L., and Gupta, R. (2020). Prediction of moisture ratios (MRs) during fluidized bed drying of ginger (Zingiber officinale) cubes by using mathematical modeling and experimental validation. Advances in Mechanical Engineering, Proceedings of the ICRIDME 2018, Shillong, India, 8\u201310 November 2018, Springer.","DOI":"10.1007\/978-981-15-0124-1_66"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1016\/j.foodres.2006.07.017","article-title":"Mathematical modelling on hot air drying of thin layer apple pomace","volume":"40","author":"Wang","year":"2007","journal-title":"Food Res. Int."},{"key":"ref_35","first-page":"415","article-title":"Estimation of the moisture diffusivity and activation energy in thin layer drying of ginger slices","volume":"7","author":"Akpinar","year":"2013","journal-title":"Int. J. Nutr. Food Eng."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"425","DOI":"10.1007\/s00231-017-2152-y","article-title":"Simultaneous application of microwave energy and hot air to whole drying process of apple slices: Drying kinetics, modeling, temperature profile and energy aspect","volume":"54","author":"Horuz","year":"2018","journal-title":"Heat Mass Transf."},{"key":"ref_37","first-page":"110","article-title":"Industrial Microwave Dryer an Effective Design to Reduce Non-Uniform Heating","volume":"14","author":"Hazervazifeh","year":"2021","journal-title":"Eng. Agric. Environ. Food"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Barbosa-C\u00e1novas, G.V., Fontana, A.J., Schmidt, S.J., and Labuza, T.P. (2020). Water Activity in Foods: Fundamentals and Applications, Institute of Food Technologists.","DOI":"10.1002\/9781118765982"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1016\/j.fshw.2015.10.001","article-title":"Functional properties, phenolic constituents and antioxidant potential of industrial apple pomace for utilization as active food ingredient","volume":"4","author":"Rana","year":"2015","journal-title":"Food Sci. Hum. Wellness"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Vlad, C.C., P\u0103cularu-Burada, B., Vasile, A.M., Milea, \u0218.A., Bahrim, G.E., R\u00e2peanu, G., and St\u0103nciuc, N. (2022). Upgrading the functional potential of apple pomace in value-added ingredients with probiotics. Antioxidants, 11.","DOI":"10.3390\/antiox11102028"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"112250","DOI":"10.1016\/j.indcrop.2020.112250","article-title":"Analysis of polyphenols in apple pomace: A comparative study of different extraction and hydrolysis procedures","volume":"147","author":"Li","year":"2020","journal-title":"Ind. Crops Prod."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1186\/s43014-023-00141-4","article-title":"Effect of microwave-assisted vacuum and hot air oven drying methods on quality characteristics of apple pomace powder","volume":"5","author":"Bhat","year":"2023","journal-title":"Food Prod. Process. Nutr."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"801","DOI":"10.1016\/j.ijbiomac.2019.08.048","article-title":"Characterization and antioxidant activity of polysaccharides obtained from ginger pomace using two different extraction processes","volume":"139","author":"Chen","year":"2019","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_44","first-page":"69","article-title":"Optimal drying conditions for valorization of industrial apple pomace: Potential source of food bioactive compounds","volume":"17","author":"Gonelimali","year":"2021","journal-title":"Prog. Agric. Eng. Sci."}],"container-title":["Processes"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2227-9717\/12\/10\/2096\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:04:18Z","timestamp":1760112258000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2227-9717\/12\/10\/2096"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,9,26]]},"references-count":44,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2024,10]]}},"alternative-id":["pr12102096"],"URL":"https:\/\/doi.org\/10.3390\/pr12102096","relation":{},"ISSN":["2227-9717"],"issn-type":[{"value":"2227-9717","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,9,26]]}}}