{"paper_id":"4c6f3e4d-9f50-4b86-bbc8-e0727a51a665","body_text":"Understanding the impact of drying on the optical properties of cured muscle tissue: a case study of dried salt-cured cod | 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 Research Article Understanding the impact of drying on the optical properties of cured muscle tissue: a case study of dried salt-cured cod Vilde Vraalstad, Annelies Postelmans, Marion O'Farrell, Jon Tschudi, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6527119/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 11 You are reading this latest preprint version Abstract Optical techniques, such as near-infrared spectroscopy (NIRS), have previously been proposed for non-destructive monitoring of the industrial dry-curing of fish and meat, but existing prediction models often lack robustness due to the complexity of these products. This study investigates the interaction of light with cured muscle tissue during drying, focusing on dried salt-cured cod within a commercially relevant range ( \\(\\qtyrange[range-units=single,range-phrase=-]{45}{56}{\\percent}\\) water content). We quantified the wavelength-dependent bulk optical properties (absorption and scattering coefficients) using double integrating sphere (DIS) measurements across the \\(\\qtyrange[range-units=single,range-phrase=-]{500}{1700}{\\nano\\meter}\\) wavelength range on \\(36\\) samples of dried salt-cured cod muscle (excluding the salt layer). Complementary histological and low-field NMR analyses helped interpret the observed trends. As expected, light absorption by water decreased during drying. This was accompanied by an increase in the anisotropy coefficient, \\(g\\) , and a corresponding decrease in the reduced scattering coefficient, \\(\\mu_s'\\) , both stabilizing below \\(50%\\) water content. A corresponding degradation of muscle microstructure, caused by increasing salt concentration, is proposed as a key mechanism behind these changes. We also observed that scattering variation was weaker than initially expected and influenced by factors such as salting methods, fibre orientation, and fish size. While this study focuses on salt-cured cod, the insights gained are also applicable to other dry-cured products, such as ham. The findings provide a fundamental understanding of the optical properties of dry-cured foods, offering valuable insights for optimising NIRS-based technologies, improving prediction models, and enabling non-invasive quality monitoring in the dry-curing industry. Optical properties Scattering Absorption Microstructure Dried salt-cured cod Cured muscle tissue Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 22 Jun, 2025 Reviews received at journal 02 Jun, 2025 Reviews received at journal 06 May, 2025 Reviewers agreed at journal 04 May, 2025 Reviewers agreed at journal 04 May, 2025 Reviewers agreed at journal 03 May, 2025 Reviewers agreed at journal 02 May, 2025 Reviewers invited by journal 02 May, 2025 Editor assigned by journal 30 Apr, 2025 Submission checks completed at journal 29 Apr, 2025 First submitted to journal 25 Apr, 2025 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. We do this by developing innovative software and high quality services for the global research community. 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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-6527119\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":452684586,\"identity\":\"97e1f934-1374-4f9a-80c5-59e0ae3823c5\",\"order_by\":0,\"name\":\"Vilde Vraalstad\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABCUlEQVRIie3QMWrDMBSA4WcEmZJ6VSjEV5DpZOLDSBTiKe3QJUMHBYGyhGZ1pl7BR5B50CwpWT02NxAUiodQqtBkaWt1zaB/EJLgQ+gBhEKXGCGSnnbyuIyAHA+5j0RnEkkwQG4ccbuJ75kfREj4h7BNNG8s4H28qNW7fRwXz4vB5s1yuIu7CEYqKwGzcis0NS/FtMIrMS85PAzl32SoIn3dhwkDIzSYHk4r0k/VoAVRGQ85OJLs9sqaTywS5ciBd5OYOOJmylgjJK01ckBHwE9UtmQ5S5u9pq9PRVo5sl5yKtYdf+nFWDftjLLR7hbt7GOcJKstsy3PxapjYt+x31fUC0KhUCjk7wssj1yia4B8YAAAAABJRU5ErkJggg==\",\"orcid\":\"\",\"institution\":\"SINTEF Digital\",\"correspondingAuthor\":true,\"prefix\":\"\",\"firstName\":\"Vilde\",\"middleName\":\"\",\"lastName\":\"Vraalstad\",\"suffix\":\"\"},{\"id\":452684587,\"identity\":\"b60b484f-45c1-47ee-90bc-8ff5df2ddfff\",\"order_by\":1,\"name\":\"Annelies Postelmans\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"KU Leuven\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Annelies\",\"middleName\":\"\",\"lastName\":\"Postelmans\",\"suffix\":\"\"},{\"id\":452684588,\"identity\":\"19776391-8246-4f3d-b06d-beaeff3cc141\",\"order_by\":2,\"name\":\"Marion O'Farrell\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"SINTEF Digital\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Marion\",\"middleName\":\"\",\"lastName\":\"O'Farrell\",\"suffix\":\"\"},{\"id\":452684589,\"identity\":\"a90aebfe-eff4-461a-8447-acb01b5b15a0\",\"order_by\":3,\"name\":\"Jon Tschudi\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"SINTEF Digital\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Jon\",\"middleName\":\"\",\"lastName\":\"Tschudi\",\"suffix\":\"\"},{\"id\":452684591,\"identity\":\"e08fcb4d-85d4-4d94-9a76-91f08ff124d3\",\"order_by\":4,\"name\":\"Jens Petter Wold\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Nofima AS - 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This study investigates the interaction of light with cured muscle tissue during drying, focusing on dried salt-cured cod within a commercially relevant range (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\qtyrange[range-units=single,range-phrase=-]{45}{56}{\\\\percent}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e water content). We quantified the wavelength-dependent bulk optical properties (absorption and scattering coefficients) using double integrating sphere (DIS) measurements across the \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\qtyrange[range-units=single,range-phrase=-]{500}{1700}{\\\\nano\\\\meter}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e wavelength range on \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(36\\\\)\\u003c/span\\u003e\\u003c/span\\u003e samples of dried salt-cured cod muscle (excluding the salt layer). Complementary histological and low-field NMR analyses helped interpret the observed trends. As expected, light absorption by water decreased during drying. This was accompanied by an increase in the anisotropy coefficient, \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(g\\\\)\\u003c/span\\u003e\\u003c/span\\u003e, and a corresponding decrease in the reduced scattering coefficient, \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\mu_s\\u0026#039;\\\\)\\u003c/span\\u003e\\u003c/span\\u003e, both stabilizing below \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(50%\\\\)\\u003c/span\\u003e\\u003c/span\\u003e water content. A corresponding degradation of muscle microstructure, caused by increasing salt concentration, is proposed as a key mechanism behind these changes. We also observed that scattering variation was weaker than initially expected and influenced by factors such as salting methods, fibre orientation, and fish size. While this study focuses on salt-cured cod, the insights gained are also applicable to other dry-cured products, such as ham. The findings provide a fundamental understanding of the optical properties of dry-cured foods, offering valuable insights for optimising NIRS-based technologies, improving prediction models, and enabling non-invasive quality monitoring in the dry-curing industry.\\u003c/p\\u003e\",\"manuscriptTitle\":\"Understanding the impact of drying on the optical properties of cured muscle tissue: a case study of dried salt-cured cod\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2025-05-07 02:39:43\",\"doi\":\"10.21203/rs.3.rs-6527119/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"decision\",\"content\":\"Revision requested\",\"date\":\"2025-06-22T20:48:29+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2025-06-02T11:55:55+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2025-05-06T12:48:21+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"148775688735280666972255617352170675437\",\"date\":\"2025-05-04T18:39:10+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"184386010782417274877828508405438013158\",\"date\":\"2025-05-04T16:00:41+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"179419680979144381414953355281533692013\",\"date\":\"2025-05-03T06:45:29+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"156101939677341953837341891681781181920\",\"date\":\"2025-05-02T17:25:19+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewersInvited\",\"content\":\"\",\"date\":\"2025-05-02T16:37:29+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorAssigned\",\"content\":\"\",\"date\":\"2025-04-30T07:02:10+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"checksComplete\",\"content\":\"\",\"date\":\"2025-04-29T21:58:49+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"submitted\",\"content\":\"Food and Bioprocess Technology\",\"date\":\"2025-04-25T08:39:26+00:00\",\"index\":\"\",\"fulltext\":\"\"}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"food-and-bioprocess-technology\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"\",\"sideBox\":\"Learn more about [Food and Bioprocess Technology](https://www.springer.com/journal/11947)\",\"snPcode\":\"11947\",\"submissionUrl\":\"https://submission.nature.com/new-submission/11947/3\",\"title\":\"Food and Bioprocess Technology\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"stoa\",\"reportingPortfolio\":\"Springer Hybrid\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false}}],\"origin\":\"\",\"ownerIdentity\":\"b9a77505-59c8-4c35-be7a-bddcb8c0e628\",\"owner\":[],\"postedDate\":\"May 7th, 2025\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"under-review\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2025-07-24T08:27:58+00:00\",\"versionOfRecord\":[],\"versionCreatedAt\":\"2025-05-07 02:39:43\",\"video\":\"\",\"vorDoi\":\"\",\"vorDoiUrl\":\"\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-6527119\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-6527119\",\"identity\":\"rs-6527119\",\"version\":[\"v1\"]},\"buildId\":\"8U1c8b4HqxoKbykW_rLl7\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}