Ring Shear Tester as an in-vitro testing tool to study oral processing of comminuted potato chips

Oral processing of solid foods is an extremely dynamic and complicated activity that involves multiple processes in tandem such as comminution, mixing, dilution, hydration and enzymatic breakdown that gradually transform the food from a morsel or a bite to a bolus that is ready for swallowing. It is hypothesised that just after "first bite" and initial particle reduction and hydration of solid brittle foods, the response to deformation of food particles is analogous to studies on the flowability and cohesion of wetted powders, which are effectively characterised using a Ring Shear Tester (RST). We examine this hypothesis and determine whether the RST measures properties of solid snack foods (potato chips or crisps, PCs) that are relevant to their dynamic sensory response, which includes capturing the effect of hydration on comminuted PCs. The RST is found to differentiate PCs obtained from different manufacturing sources (e.g. baked versus fried), and its measurements of cohesion and friction can be considered in context of the structure and composition of the PCs as well as oral processing. Remarkably, RST measurements for this small set of PC samples correlate with several sensory attributes that arise during mastication, which includes Sharpness and Ease of Clearance. This study highlights the potential of the RST as a new tool for oral processing research.