Method for raising yield of xylooligosaccharide

Abstract

The invention discloses a method for raising the yield of xylooligosaccharide and belongs to the fields of chemical engineering and food. The method comprises of treating corn straw as the raw material, firstly, sequentially conducting air drying and pulverization, conducting soaking treatment with water and ethyl alcohol for removing water soluble impurities and fat soluble impurities in the raw material, and then conducting lignin removal treatment through a sodium chlorite method; secondly, obtaining a xylan extracting solution through an alkaline extraction method, and after pH is adjusted to be neutral, conducting concentration for removing salt; finally, conducting depolymerization treatment on xylan through an enzymolysis method and an acidolysis method in sequence, and conducting centrifugation, activated carbon treatment and freeze-drying, so that a xylooligosaccharide product is obtained. The method has the following advantages that xylan liquid obtained through the method is subjected to a hydrolysis reaction, and the complex separating and drying steps in the preparation process are omitted; enzymolysis residues are subjected to acetic acid treatment at the high temperature, the yield of the xylooligosaccharide can be raised, and no excessive influence can be caused to the acidic and basic property of the product; the straw is utilized as the raw material, so that good economic benefits and ecological significance are achieved.

Description

technical field [0001] The invention relates to a method for increasing the yield of xylooligosaccharides, which belongs to the technical fields of chemical industry and food. Background technique [0002] At present, the hydrolysis methods for degrading hemicellulose into xylooligosaccharides are mainly divided into four types: enzymatic hydrolysis, acid hydrolysis, self-hydrolysis, and chemical enzymatic hydrolysis. Among them, enzymatic hydrolysis relies on its mild reaction conditions and low pollution. , has become the mainstream method for the preparation of xylooligosaccharides. However, at present, the yield of xylo-oligosaccharides produced by single enzymatic or acid hydrolysis is generally not high. Insufficient binding sites for enzymes and sugars, etc. Acid degradation is more thorough, but there is no specificity of bond breaking. Therefore, if a method of organically combining enzymatic hydrolysis and acid hydrolysis to achieve a higher yield of xylo-oligos...

AI Technical Summary

Problems solved by technology

[0003] China Agricultural University disclosed the "preparation method of xylooligosaccharides" (application number 01131171.1), using various corn cobs as raw materials, after pretreatment with alkali metal hydroxides, direct pyrolysis under the action of a weak acid catalyst, and then using Enzymatic preparation of xylo-oligosaccharides, and finally refined to obtain high-purity xylo-oligosaccharide products, but the yield of this invention is low, and there is no further treatment of the hydrolysis residue, resulting in the waste of some hemicellulose components

Li Xiufang and others disclosed "the method of using biological straw to prepare xylo-oligosaccharides, dissolving pulp and bio-fuel". The residual enzymolysis slag after enzymolysis was pulped, washed and screened, delignified, pretreated, and bleached. Prepare a series of treatments such as dissolving pulp, so as to utilize the enzymolysis residue. The process of this invention is complicated and consumes a lot of energy