Joint Mathematics-Physics Colloquium: Multi-scale mechanics of soft materials, complex fluids and plant cell walls, and its application to food structure design

Stokes

**NOTE TIME HAS CHANGED**

A/Prof. Jason Stokes, UQ
This colloquium has been postponed. New time TBA.

Foods are highly complex soft matter systems that contain hierarchical structures and multiple phases, and rheology is used as an essential tool for their design [1]. However, food is subject to multi-scale deformations during oral processing as it is transformed to a swallowable bolus, and the physical mechanisms governing the dynamics of taste, texture and mouthfeel perception are complex and not well understood. Here I highlight our recent advances to combat such complexity, and our development of physical techniques that enable in vitro measurement of relevant material properties of food systems, which span liquids, multiphase fluids and brittle solids. We seek to probe the physics experienced during oral processing and the interactions occurring with saliva and the mucosal films lining oral surfaces. We have been particularly instrumental in developing new soft-tribology (friction, lubrication), gap-dependent rheology and surface-film analysis techniques to provide potential approaches for rational design [2] and deliver foods and beverages with superior mouthfeel and acceptability whilst delivering benefits to health and well-being of consumers.

This presentation will also highlight other research activities in the group, including: developments to measure experimentally, and interpret computationally, the micromechanical properties of soft materials including microgel suspensions [3], plant cells [4], and poroelastic cellulose hydrogels [5]; and aqueous polymer lubrication [6].

[1] Stokes JR, WJ Frith, Soft Matter, 4, 1133 – 1140, (2008).

[2] Stokes JR, MW Boehm, SK Baier Current Opinion in Colloid & Interface Sci 18 (4), 349-359 (2013)

[3] Shewan HM, JR Stokes Journal of Colloids and Interface Science 442, pp. 75-81(2015)

[4] Bonilla MR, JR Stokes, MJ Gidley, GE Yakubov Soft Matter 11 (7), pp. 1281-1292 (2015)

[5] Lopez-Sanchez, et al. Biomacromolecules 15 (6), pp. 2274-2284 (2015)

[6] Stokes JR, et al Langmuir, 27 (7), pp. 3474-3484 (2011)