Properties of foamed concrete utilizing Fe(II) as foam stabilizer for hydrolyzed pumpkin seed protein

Properties of foamed concrete utilizing Fe(II) as foam stabilizer for hydrolyzed pumpkin seed protein | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Properties of foamed concrete utilizing Fe(II) as foam stabilizer for hydrolyzed pumpkin seed protein Ning Song, Zhongfeng Zhang, Wei Li, Guangqi Hu, Shaoqing Wang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8526017/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 10 Mar, 2026 Read the published version in Scientific Reports → Version 1 posted 10 You are reading this latest preprint version Abstract This paper introduces a novel strategy for the fabrication of ultra-stable protein foams mediated by transition metal ions. Specifically, the transition metal ion Fe(II) was utilized as the foam stabilizer for hydrolyzed pumpkin seed protein (HPSP) in this study. To maximize foaming performance, response surface methodology (RSM) was utilized to optimize key process parameters in hot-alkali experimental setups. The experimental findings indicated that the optimal reaction conditions were identified as a pH of 11.5, a temperature of 55 ℃, and a reaction time of 1.5 h; under these conditions, the HPSP foaming agent exhibited the highest foaming volume of 488 mL. The interaction and the mechanism of foam stabilization between transition metal ions Fe(II) and HPSP were studied. The results of high performance liquid chromatography (HCLP) showed that the HPSP solution contained a large amount of isoleucine which was beneficial to the stability of foam. Low temperature transmission electron microscopy (Cryo TEM) and small angle X-ray scattering (SAXS) experiments have confirmed that the addition of Fe(II) promotes the exposure of hydrophobic groups in proteins and increases the size of aggregates. Meanwhile, the properties of foam and foamed concrete prepared using self-made foaming agent (Fe-HPSP) and plant protein foaming agents readily available on the market (PS) were studied. Experimental findings reveal that HPSP foams incorporating Fe(II) exhibit enhanced density, stability and viscosity. Furthermore, the resistance to shrinkage and homogeneity of the resultant foamed concrete are also improved. This research offers a novel strategy for the advancement of protein-based foaming agents. Physical sciences/Chemistry Physical sciences/Engineering Physical sciences/Materials science Transition metal ions Hydrolyzing pumpkin seed protein Foam stabilizer Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 10 Mar, 2026 Read the published version in Scientific Reports → Version 1 posted Editorial decision: Revision requested 16 Feb, 2026 Reviews received at journal 05 Feb, 2026 Reviews received at journal 01 Feb, 2026 Reviewers agreed at journal 30 Jan, 2026 Reviewers agreed at journal 29 Jan, 2026 Reviewers invited by journal 28 Jan, 2026 Editor assigned by journal 27 Jan, 2026 Editor invited by journal 27 Jan, 2026 Submission checks completed at journal 12 Jan, 2026 First submitted to journal 12 Jan, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8526017","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":588012095,"identity":"b05623bb-f99a-4ee1-b2d4-5a950d87189b","order_by":0,"name":"Ning Song","email":"","orcid":"","institution":"Shangdong Agriculture and Engineering University","correspondingAuthor":false,"prefix":"","firstName":"Ning","middleName":"","lastName":"Song","suffix":""},{"id":588012096,"identity":"daf85556-8a82-410a-9ed3-a632093ec1d2","order_by":1,"name":"Zhongfeng Zhang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAxklEQVRIiWNgGAWjYBACfoYDiQ8+/LCRs29vIFKLZOOBx4Yze9KMDXgOEKnF4PDBZ9I8bIcTN0gkEGtL2+E0yRk8zIzbJR9vvMFQYxNNUAs/z7Fkiw8WbMyWs9OKLRiOpeU2ELRlxpnEmzN4eNgYbueYSTA2HCasxeD++w9Av0jwMNw8Q6yWAweSgFoMJAxu8BCpRbLhQDIwkBMMJHuAfkkgxi/QqPxf389+eOONDzU2hLWgOJLoqEHSQqqOUTAKRsEoGBkAAC/KRbUMgiX5AAAAAElFTkSuQmCC","orcid":"","institution":"Shangdong Agriculture and Engineering University","correspondingAuthor":true,"prefix":"","firstName":"Zhongfeng","middleName":"","lastName":"Zhang","suffix":""},{"id":588012097,"identity":"94d28e76-5d0d-45ba-a897-c1023d4a5646","order_by":2,"name":"Wei Li","email":"","orcid":"","institution":"Shangdong Agriculture and Engineering University","correspondingAuthor":false,"prefix":"","firstName":"Wei","middleName":"","lastName":"Li","suffix":""},{"id":588012098,"identity":"ebacee6d-9e3e-44d0-aee5-9e37b658ab79","order_by":3,"name":"Guangqi Hu","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Guangqi","middleName":"","lastName":"Hu","suffix":""},{"id":588012099,"identity":"bfac99fa-2614-48f7-a8b9-1e82dbc58546","order_by":4,"name":"Shaoqing Wang","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Shaoqing","middleName":"","lastName":"Wang","suffix":""}],"badges":[],"createdAt":"2026-01-06 03:08:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8526017/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8526017/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41598-026-43413-y","type":"published","date":"2026-03-10T15:59:49+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":104739784,"identity":"5f80a795-97e6-4a25-a70c-e5e03330d4ef","added_by":"auto","created_at":"2026-03-16 16:12:46","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1166995,"visible":true,"origin":"","legend":"","description":"","filename":"revisedmunscriptwithchangesmarked.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8526017/v1_covered_dbf017d9-de48-4f7b-a365-b16f55b75e40.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Properties of foamed concrete utilizing Fe(II) as foam stabilizer for hydrolyzed pumpkin seed protein","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Transition metal ions, Hydrolyzing pumpkin seed protein, Foam stabilizer","lastPublishedDoi":"10.21203/rs.3.rs-8526017/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8526017/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis paper introduces a novel strategy for the fabrication of ultra-stable protein foams mediated by transition metal ions. 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