Preparation method of vegetable protein fiber

The invention provides a preparation method of plant protein fibers, which comprises the following steps: taking a certain amount of soybean-lotus seed protein material, adding natural auxiliary materials, tempering to obtain a soybean-lotus seed protein mixture, then carrying out extrusion fibrosis treatment on the soybean-lotus seed protein mixture in a screw extruder, and cooling to obtain soybean-lotus seed compound protein fibers. The soybean protein isolate and the lotus seed protein isolate are compounded, nutritional ingredients of the protein fiber are increased, the sensory quality of the protein fiber is improved, the protein fiber is compact and stable in structure and high in texturization degree, and the two different food components of linoleic acid and potato amylopectin are adopted as the auxiliary materials, so that the nutritional protein fiber has a good taste. The two components have a synergistic effect on the change of the protein fiber structure, so that the formation of the protein fi