{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T17:57:06Z","timestamp":1788544626835,"version":"build-2803163510"},"reference-count":40,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2025,6,27]],"date-time":"2025-06-27T00:00:00Z","timestamp":1750982400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>This study systematically investigates how thiol\u2013disulfide interactions influence the structure and mechanical properties of casein gels. Acid gels were prepared from suspensions of micellar casein (MC) powder that were heat-treated at 70 \u00b0C. Thiol groups were variably blocked with N-ethylmaleimide (NEM). The gels were characterized using stress\u2013strain measurements, rheological analyses, and confocal microscopy. The stress\u2013strain curves exhibited a biphasic behavior, with an initial linear elastic phase followed by a linear plastic region and a nonlinear failure zone. Compared to control samples, the addition of 100 mM NEM reduced the gel strength by 50%, while G\u2032 and G\u2033 increased by around 100%, unexpectedly. NEM-treated gels consist of uniformly sized building blocks coated with a whey protein layer. Strong physical interactions and dense packing enhance viscoelasticity under short deformations but reduce the compressive strength during prolonged loading. In contrast, control samples without NEM demonstrate weak viscoelasticity and increased compressive strength. The former is attributed to a broader particle size distribution from lower acid stability in the untreated gels, while the particularly high compressive strength of heat-treated gels additionally results from disulfide cross-links. The results show that thiol blocking and heating enable the targeted formation of acid casein gels with high shear stability but a low compressive strength.<\/jats:p>","DOI":"10.3390\/ijms26136206","type":"journal-article","created":{"date-parts":[[2025,7,1]],"date-time":"2025-07-01T05:28:28Z","timestamp":1751347708000},"page":"6206","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Tuning the Gel Network Structure and Rheology of Acid-Induced Casein Gels via Thiol Blocking"],"prefix":"10.3390","volume":"26","author":[{"given":"Thomas","family":"P\u00fctz","sequence":"first","affiliation":[{"name":"Chair of Soft Matter Process Engineering (AVT.SMP), RWTH Aachen University, 52074 Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9702-1996","authenticated-orcid":false,"given":"Ronald","family":"Gebhardt","sequence":"additional","affiliation":[{"name":"Chair of Soft Matter Process Engineering (AVT.SMP), RWTH Aachen University, 52074 Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"138956","DOI":"10.1016\/j.foodchem.2024.138956","article-title":"Casein-based hydrogels: Advances and prospects","volume":"447","author":"Yang","year":"2024","journal-title":"Food Chem."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"114","DOI":"10.1016\/j.foodhyd.2017.03.013","article-title":"Effect of the pH and NaCl on the microstructure and rheology of mixtures of whey protein isolate and casein micelles upon heating","volume":"70","author":"Nguyen","year":"2017","journal-title":"Food Hydrocoll."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"909","DOI":"10.1007\/s00396-020-04802-5","article-title":"A regenerated fiber from rennet-treated casein micelles","volume":"299","author":"Thill","year":"2021","journal-title":"Colloid Polym. 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