Method for preparing food-grade xylo-oligosaccharide from viscose fiber squeezed alkali solution

Abstract

The invention provides a method for preparing food-grade xylo-oligosaccharide from a viscose fiber squeezed alkali solution. The technology comprises the following steps: step A, membrane condensation: pre-filtering the squeezed alkali solution, which is generated during the production process of viscose fibers, to remove the large particle impurities, adding water into the filtrate to dilute the filtrate, then processing the diluted filtrate by a primary nano-filter membrane so as to obtain primary concentrate, adding water to dilute the primary concentrate, then processing the diluted primary concentrate by a secondary nano-filter membrane so as to obtain the secondary concentrate, diluting the secondary concentrate by water, then processing the diluted secondary concentrate by a ceramic membrane so as to obtain the concentrate namely the concentrate of squeezed alkali solution; step B, semi-fiber extraction: adding acid into the obtained concentrate to neutralize the alkali solution so as to obtain a semi-fiber solution; step C, enzymatic hydrolysis: adding composite enzymes into the semi-fiber solution to carry out enzymatic hydrolysis so as to obtain enzymatic hydrolysate; step D, purification: filtering the enzymatic hydrolysate by a ceramic membrane, then filtering the filtrate by a nano-filter membrane to remove the salts, decoloring the obtained concentrate by active carbon, then making the concentrate go through a resin column to carry out ion exchange so as to obtain a purified xylo-oligosaccharide solution, and finally evaporating and drying the solution so as to obtain food-grade xylo-oligosaccharide.

Description

technical field [0001] The invention relates to the field of xylo-oligosaccharide preparation, in particular to a process for producing food-grade xylo-oligosaccharide by using viscose fiber pressed lye as raw material. Background technique [0002] Xylooligosaccharides, also known as xylooligosaccharides, are a general term for branched chain oligosaccharides formed by combining 2-7 xyloses with β-1,4-glycosidic bonds. The active ingredients are xylobiose, xylotriose, xylotetraose, xylopentose, etc., among which xylobiose and xylotriose are the main ones. Compared with soybean oligosaccharides, fructooligosaccharides, and isomaltose oligosaccharides, which are commonly used by people, xylooligosaccharides have unique advantages. It can selectively promote the proliferation of intestinal bifidobacteria, and its bifidus factor function It is 10-20 times that of other polysaccharides. Xylo-oligosaccharides are considered to be ideal health food sweeteners because of their si...

AI Technical Summary

Problems solved by technology

The nanofiltration membrane concentration temperature of this process is low, and the membrane filtration efficiency is low, which is not suitable for industrial large-scale production