EFFECT OF SPECIFIC MECHANICAL ENERGY DURING EXTRUSION ON THE PROPERTIES OF EXTRUDED PROTEIN-STARCH MIXTURES

摘要

Specific mechanical energy (SME) was reported to be responsible for fragmentation of starch molecules, as a result of the effect of shear forces on amylopectin molecules. Some researchers reported a decrease in the product's glass transition temperature (Tg) with the increase of SME. In contrast to starch degradation, it was reported that proteins are more resistant to the shear forces and do not fragment during extrusion. The objective of this research was to study the effect of SME on the glass transition, gelatinization and microstructure of mixed protein/starch systems and to examine the validity of the degradation models in explaining the Tg vs SME results. The effect of specific mechanical energy during extrusion of a protein/starch mixture was studied by analyzing the product's Tg and starch gelatinization.