Rheometer for characterizing the mechanical properties of food materials

点击翻译按钮获取中文摘要

To improve the quality of novel and existing foods, their physical properties need to be quantitatively characterized and better understood at various stages of processing and during storage. This application requests the purchase of a HR-2 Discovery Hybrid Rheometer to be used in characterizing the changes in mechanical properties of food materials as they are exposed to a wide range of temperature and pressure conditions and at various deforming stress rates that foods go through during manufacturing. With the purchase of this rheometer, Drs. Koksel, Scanlon, Aluko and Erkinbaev will have access to tools to investigate the mechanical properties of foods ranging from expanded snacks, vegetarian/vegan burger patties and bread doughs to food suspensions, protein gels and protein-rich foams. A major part of Koksel's research involves elucidating how novel structures are formed in protein enriched aerated foods that are crispy and crunchy, and texturized plant-based meats' that are able to mimic the juicy and fibrous nature of animal muscle meat. Measurement of both these structure formation pathways requires a pressure- and temperature-controlled rheometer. Another research direction (Scanlon) is to identify the compositional and structural bases that govern the viscoelastic behaviour of wheat flour doughs and to establish simple reliable models of their constitutive properties. This line of research is scientifically interesting and also practically relevant to the bakery industry due to dough handling difficulties and product quality issues induced by changes in formula. Scanlon's research program involves studies of the complex flow properties of food suspensions during processing, for which a high sensitivity rheometer is essential so as to measure elasticity development as a function of solid content in these particulate food slurries. For Aluko, fundamental rheological investigations of structure-function relationships in food protein gels as affected by processing parameters and intrinsic protein structures will lead to the discovery of novel protein gels. Erkinbaev's research on the role of plant protein surfactants in foam mechanical properties will complement the optical measurements from his lab, unraveling how foam texture and mouth feel are affected in conventional and novel foods. All of the above projects require very sensitive temperature control and a rheometer with a low compliance to enable high precision measurements of the mechanical properties of model and complex food systems. Without a new rheometer, our publications do not have as high an impact in the scientific community, due to the limited scope and restrictive nature of the data produced using our current rheometer. Should our current 19-years-old rheometer (or any of its parts), that is heavily used and no longer supported for service, fail, the research programs of the applicants and training of their HQP will be severely interrupted.