{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T03:28:31Z","timestamp":1787801311353,"version":"build-2784847793"},"reference-count":37,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2021,10,11]],"date-time":"2021-10-11T00:00:00Z","timestamp":1633910400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001321","name":"National Research Foundation","doi-asserted-by":"publisher","award":["129642"],"award-info":[{"award-number":["129642"]}],"id":[{"id":"10.13039\/501100001321","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The infrared heating of preconditioned cowpea improves its utilization and potential application in food systems. This study investigated the effect of optimizing preconditioning and infrared heating parameters of temperature and time on cooking characteristics of precooked cowpeas using response surface methodology (RSM). The moisture level (32\u201357%), infrared heating temperature (114\u2013185 \u00b0C), and time of processing the seeds (2\u201318 min) were optimized using a randomized central composite design to achieve optimal characteristics for bulk density and water absorption. A second-order polynomial regression model was fitted to the obtained data, and the fitted model was used to compute the multi-response optimum processing conditions, which were the moisture of 45%, the heating temperature of 185 \u00b0C, and time of 5 min. Precooked cowpea seeds from optimized conditions had a 19% increase in pectin solubility. The total phenolic and total flavonoid contents were significantly reduced through complexation of the seeds\u2019 phenolic compounds with other macromolecules but nonetheless exhibited antioxidant properties capable of scavenging free radicals. There was also a significant reduction in phytate and oxalates by 24% and 42%, respectively, which was due to the heat causing the inactivation of these antinutrients. The obtained optimized conditions are adequate in the production of precooked cowpea seeds with improved quality.<\/jats:p>","DOI":"10.3390\/molecules26206137","type":"journal-article","created":{"date-parts":[[2021,10,11]],"date-time":"2021-10-11T21:45:32Z","timestamp":1633988732000},"page":"6137","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Optimization of Infrared Heating Conditions for Precooked Cowpea Production Using Response Surface Methodology"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6264-8879","authenticated-orcid":false,"given":"Opeolu M.","family":"Ogundele","sequence":"first","affiliation":[{"name":"Department of Biotechnology and Food Technology, Faculty of Science, Doornfontein Campus, University of Johannesburg, Johannesburg P.O. Box 17011, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7869-0484","authenticated-orcid":false,"given":"Sefater","family":"Gbashi","sequence":"additional","affiliation":[{"name":"Department of Biotechnology and Food Technology, Faculty of Science, Doornfontein Campus, University of Johannesburg, Johannesburg P.O. Box 17011, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5760-541X","authenticated-orcid":false,"given":"Samson A.","family":"Oyeyinka","sequence":"additional","affiliation":[{"name":"Department of Biotechnology and Food Technology, Faculty of Science, Doornfontein Campus, University of Johannesburg, Johannesburg P.O. Box 17011, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eugenie","family":"Kayitesi","sequence":"additional","affiliation":[{"name":"Department of Consumer and Food Science, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3757-5137","authenticated-orcid":false,"given":"Oluwafemi A.","family":"Adebo","sequence":"additional","affiliation":[{"name":"Department of Biotechnology and Food Technology, Faculty of Science, Doornfontein Campus, University of Johannesburg, Johannesburg P.O. Box 17011, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Gomes, A.M.F., Draper, D., Nhantumbo, N., Massinga, R., Ramalho, J., Marques, I., and Ribeiro-Barros, A. (2021). 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