Abstract
Texturized defatted soy flour was separated into protein fractions or lumps. The lumping technique consisted of successive solubilization of the capillary rheometer extrudate in water, buffer, mercaptoethanol, and sodium dodecyl sulfate solutions. The lumps were then used to study the protein reactions during the texturization process. The kinetics were modeled using a first order rate temperature-dependent monomolecular reaction network. Three models were obtained, with 16, 15, and 14 constants, respectively. These models predicted the experimental results very closely. The extrudate was also analyzed using dynamic compressive modulus and the associated phase angle. Results showed a dependence of the modulus with time. The phase angle was dependent on time and on shear rate. No appreciable slip could be detected at the die wall during the capillary rheometer extrusions. Rheological tests and the chemical fractions were correlated to find the relationships and the type of proteins responsible for the behavior of the extrudate. The insoluble protein fraction was found to be the most significantly correlated with dynamic compressive modulus. Phase angle was correlated with the insoluble fraction, but the mercaptoethanol soluble fraction had a major contribution. Effective viscosity was affected by the buffer-soluble and insoluble fractions.
Arce, Javier Antonio (1982). Kinetics of soy flour protein reactions during texturization. Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -284651.