The research supported by the Presidential Young Investigator Award is the theoretical and experimental analysis of extrusion of biological materials. One of the difficulties in predicting parameters, for instance flow rate, in extrusion processing is that most biopolymers undergo chemical reactions during extrusion-cooking. These chemical reactions significantly change the rheological behavior of the material. The objective of the study is to develop a mathematical model to predict the interaction of rheological behavior, time-temperature history and reaction rate. The experimental studies to verify the model will utilize magnetic resonance imaging. Magnetic resonance imaging will provide a quantitative evaluation of the velocity profile of fluid in the extruder during operation. FY 90 - PYI, First Year $25,000
