Abstracts Engineering

A fundamental mechanical analysis of the texture of french fries

by Kelly Anne Ross

This thesis attempted to understand how mechanical parameters characterizing the textural properties of french fries could be derived from indentation tests. The focus of the first part of this study was to obtain a fundamental mechanical parameter, the elastic modulus, of a model food system (an agar gel), from the indentation test. The focus of the second part of this study was to use a fundamental engineering approach to quantify the mechanical properties of the fried potato crust. The effect of frying time on the mechanical properties of fried potato crust was investigated and values for the fracture stress, fracture strain, elastic modulus, and fracture toughness of the fried potato crust were quantified. The focus of the third part of his study was to apply a full mechanics approach to the indentation analysis of a biological composite material. A 3% agar gel was modeled as the core of the composite material and fried potato crusts of various thicknesses were modeled as the facesheets of the composite material to simulate the structure of a french fry with the aim of characterizing the indentation process. Using a theory which incorporated small plate deformation theory and plastic deformation theory, and membrane deformation theory, the load-deformation response of this biological composite material was characterized. (Abstract shortened by UMI.)