Egg yolk as a model for gelation: From rheometry to flow physics

Marsh, Maxwell C. [Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign , Urbana, Illinois 61801, and Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, USA] (ORCID:0009000721935947); Hossain, Mohammad Tanver [Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign , Urbana, Illinois 61801, and Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, USA] (ORCID:0000000272350427); Ewoldt, Randy H. [Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign , Urbana, Illinois 61801, and Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, USA] (ORCID:0000000327209712)

doi:10.1063/5.0255929

DOE OSTI · 2860658

Egg yolk as a model for gelation: From rheometry to flow physics

Marsh, Maxwell C. [Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign , Urbana, Illinois 61801, and Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, USA] (ORCID:0009000721935947)·Hossain, Mohammad Tanver [Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign , Urbana, Illinois 61801, and Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, USA] (ORCID:0000000272350427)·Ewoldt, Randy H. [Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign , Urbana, Illinois 61801, and Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, USA] (ORCID:0000000327209712)

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Abstract

Egg yolks are an excellent model for studying sol-gel transitions, particularly the power law viscoelasticity that defines the critical point of gelation. However, prior studies lack comprehensive datasets and fail to visualize flow behavior linked to temperature and time-dependent linear and nonlinear rheology. Here, we present a detailed dataset characterizing egg yolk viscoelasticity across temperature, time, and forcing amplitude using oscillatory shear, step strain, step stress, and constant high strain rate. Novel protorheology visualizations link rheological properties with observable flow behavior. Our findings highlight the nuanced determination of the critical gel point, emphasizing observation timescale dependencies. We compare methods to identify critical temperatures for gelation, including power law viscoelasticity, moduli crossover, diverging zero-shear viscosity, and emerging equilibrium elastic modulus, while visualizing flow consequences near these transitions. Egg yolk is an accessible, realistic, and nontoxic material relevant to the physicist and the chef alike, making it ideal for understanding the rheology of critical gels. By integrating protorheology photos and videos with rigorous rheometric data, we deepen the understanding of critical gels, with broader impacts for studying other materials with sol-gel transitions.

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Marsh, Maxwell C. [Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign , Urbana, Illinois 61801, and Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, USA] (ORCID:0009000721935947), Hossain, Mohammad Tanver [Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign , Urbana, Illinois 61801, and Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, USA] (ORCID:0000000272350427), Ewoldt, Randy H. [Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign , Urbana, Illinois 61801, and Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, Illinois 61801, USA] (ORCID:0000000327209712). 2025-04-08. Egg yolk as a model for gelation: From rheometry to flow physics. https://doi.org/10.1063/5.0255929

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