Die dimensions impact on fibrous plant protein formation during high moisture extrusion.

Plant-based meat analogues that mimic the structure and texture of meat are becoming very popular. They can be produced using high moisture extrusion (HSE). High protein materials first undergo intense thermomechanical treatment in the extruder barrel and then are textured and simultaneously cooled in the die. The mechanisms underlying this structuring process are not sufficiently understood and depend on numerous and interconnected factors, including raw materials composition and process parameters. This study focuses on the effects of die height and die length on extruder responses (torque, pressure), textural properties and fibration of soy concentrate extrudate obtained at high moisture (60% w/w). In order to evaluation the quality of fibration, and to complete texture analysis, a visual method base on angle of fibration was developed. By comparing extrudate obtained with die of 2mm and 5mm height, this study shows that a minimum height is necessary for temperature gradient and velocity profile...