Investigating indentation as a means of evaluating the constitutive properties of biological materials

加工食品是一种非常复杂的材料，在食品加工操作的各种热量、质量和动量传递事件中产生的微观结构决定了食品的性质。破解这种复杂性是准确预测新型和传统食品质量的关键，也是开发成功的营养负荷策略以创造健康功能食品的关键。这一发现基金的研究重点是研究两种重要的食品材料，并表征它们的弹性和随时间变化的行为。计算技术将被用来处理时间依赖行为给这些材料的压痕过程分析增加的复杂性。[压痕是一种将探头插入材料表面的技术，通过测量探头在移位到材料中时所受的力来评估材料的机械性能。它是检查食品等软材料易碎结构的理想方法，因为它避开了可能具有破坏性的样品制备程序，但可用于确定基本的机械性能。]通过了解如何从压痕试验中反提取基本机械性能，这项研究将使压痕成为一种简单、快速的工具，用于评估生物材料的机械性能。此外，对两类具有网络结构的重要食品材料的力学行为进行系统评价，可能会发现新的物理现象，从而导致新的生物本构模型的发展。从这些模型中获得的关于如何在加工过程中优化食品质量的见解将使加工商能够配制出更健康的食品，保留传统食品的质量属性，从而减少加拿大与饮食有关的疾病的发生率。

Processed foods are wonderfully complex materials where the microstructures created during the various heat, mass and momentum transfer events of food process operations determine the properties of the food. Unravelling this complexity is the key to accurately predicting the quality of novel and conventional foods, and to developing successful nutrient loading strategies for the creation of healthy functional foods. The research of this Discovery grant is focused on studying two important food materials and characterizing their elastic and time-dependent behaviour. Computational techniques will be used to cope with the complexity that time-dependent behaviour adds to analyses of the indentation process of these materials. [Indentation is a technique where a probe is inserted into the surface of a material and the mechanical behaviour of the material is assessed through measurement of force on the probe as it is displaced into the material. It is an ideal method for examining the fragile structures of soft materials such as foods because it circumvents potentially destructive sample preparation procedures, yet it can be used to determine fundamental mechanical properties.] By understanding how to back-extract fundamental mechanical properties from indentation tests, the research will enable indentation to be developed as a simple rapid tool for evaluations of the mechanical properties of biological materials. In addition, a systematic evaluation of the mechanical behaviour of two important classes of food materials possessing a network structure can potentially uncover novel physical phenomena, and so lead to the development of new biological constitutive models. Insights gained from these models on how food quality can be optimized during processing will allow processors to formulate healthier foods that retain the quality attributes of conventional foods, and thereby reduce the incidence of diet-related disease in Canada.