As a dry amorphous food system absorbs moisture or increases in temperature, the brittle food becomes soft and deformable. The temperature at which this transition occurs in the food system for a given moisture content is called the brittle-ductile transition temperature (Tb). Three different methods of determining this transition were used. The method that was chosen to best describe the food system was the intersection of brittle strength and yield strength measured in flexure as a function of both temperature and moisture content. Tb decreased linearly with increasing moisture content with a strong linear relationship (r2 = 0.98).
Bibliographical noteFunding Information:
We thank Dr. Lorraine Francis and Dr. Karl Yoder (University of Minnesota Department of Materials Science and Chemical Engineering) for their input on the force-deformation method development and analysis. We would also like to thank Dr. Frank Martin and Dr. Bingham (University of Minnesota Department of applied Statistics) for their suggestions regarding bootstrapping. This research was supported through a USDA National Needs Research Fellow Grant, the University of Minnesota Agricultural Experiment Station Project 18–72 and the Institute of Food Technologists’ Marcel Loncin Research Award.
- Brittle-ductile transition
- Moisture content