Tribological measurements of foods using a rheometer

The oral processing of foods occurs under a range of mechanical conditions, from bulk deformation and flow to confined, thin film sliding and shearing. Recently, there has been an impetus in studying the lubrication and breakdown behaviour of food hydrocolloids and emulsions under confined sliding conditions to better mimic in-mouth processes. Thus, the aim of the current work was to investigate a new method for measuring the tribological properties of food materials when one or both contacting surfaces are soft. For this purpose, a tribology cell was made that can be attached to a rheometer. This paper presents early validation work of the technique using Newtonian fluids of different viscosities. The friction data show that different regimes of lubrication could be captured using solutions with different viscosities, suggesting the promise of the system for measuring lubrication properties under a range of speed and normal load conditions.