{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,19]],"date-time":"2026-01-19T14:04:37Z","timestamp":1768831477485,"version":"3.49.0"},"reference-count":50,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,12,9]],"date-time":"2021-12-09T00:00:00Z","timestamp":1639008000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/BTA-BTA\/30902\/2017)"],"award-info":[{"award-number":["PTDC\/BTA-BTA\/30902\/2017)"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BD\/111911\/2015"],"award-info":[{"award-number":["SFRH\/BD\/111911\/2015"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["strategic funding of UIDB\/04469\/2020 unit,"],"award-info":[{"award-number":["strategic funding of UIDB\/04469\/2020 unit,"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Fermentation"],"abstract":"<jats:p>The hydrocarbon-based economy is moving at a large pace to a decarbonized sustainable bioeconomy based on biorefining all types of secondary carbohydrate-based raw materials. In this work, 50 g L\u22121 in COD of a mixture of food waste, brine and wastewater derived from a biodiesel production facility were used to produce organic acids, important building-blocks for a biobased industry. High salinity (12\u201318 g L\u22121), different reactors configuration operated in batch mode, and different initial pH were tested. In experiment I, a batch stirred reactor (BSR) at atmospheric pressure and a granular sludge bed column (GSBC) were tested with an initial pH of 5. In the end of the experiment, the acidification yield (\u03b7a) was similar in both reactors (22\u201324%, w\/w); nevertheless, lactic acid was in lower concentrations in BSR (6.3 g L\u22121 in COD), when compared to GSBC (8.0 g L\u22121 in COD), and valeric was the dominant acid, reaching 17.3% (w\/w) in the BSR. In experiment II, the BSR and a pressurized batch stirred reactor (PBSR, operated at 6 bar) were tested with initial pH 7. The \u03b7a and the VFA concentration were higher in the BSR (46%, 22.8 g L\u22121 in COD) than in the PBSR (41%, 20.3 g\/L in COD), and longer chain acids were more predominant in BSR (24.4% butyric, 6.7% valeric, and 6.2% caproic acids) than in PBSR (23.2%, 6.2%, and 4.2%, respectively). The results show that initial pH of 7 allows achieving higher \u03b7a, and the BSR presents the most suitable reactor among tested configurations to produce VFA from wastes\/wastewaters with high salinity.<\/jats:p>","DOI":"10.3390\/fermentation7040303","type":"journal-article","created":{"date-parts":[[2021,12,10]],"date-time":"2021-12-10T02:07:18Z","timestamp":1639102038000},"page":"303","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Volatile Fatty Acids (VFA) Production from Wastewaters with High Salinity\u2014Influence of pH, Salinity and Reactor Configuration"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4645-908X","authenticated-orcid":false,"given":"Maria Salom\u00e9","family":"Duarte","sequence":"first","affiliation":[{"name":"CEB\u2014Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9380-8428","authenticated-orcid":false,"given":"Jo\u00e3o V.","family":"Oliveira","sequence":"additional","affiliation":[{"name":"CEB\u2014Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal"}]},{"given":"Carla","family":"Pereira","sequence":"additional","affiliation":[{"name":"CEB\u2014Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal"}]},{"given":"Miguel","family":"Carvalho","sequence":"additional","affiliation":[{"name":"CEB\u2014Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal"}]},{"given":"Daniela P.","family":"Mesquita","sequence":"additional","affiliation":[{"name":"CEB\u2014Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal"}]},{"given":"Maria Madalena","family":"Alves","sequence":"additional","affiliation":[{"name":"CEB\u2014Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1016\/j.wasman.2017.11.033","article-title":"Comparison of the acidogenic and methanogenic potential of agroindustrial residues","volume":"72","author":"Perimenis","year":"2018","journal-title":"Waste Manag."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1016\/j.biortech.2017.06.121","article-title":"Enhanced volatile fatty acids production from anaerobic fermentation of food waste: A mini-review focusing on acidogenic metabolic pathways","volume":"248","author":"Zhou","year":"2018","journal-title":"Bioresour. 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