Preparation method for carboxyethyl welan gum

Abstract

The invention discloses a preparation method for a carboxyethyl welan gum. The preparation method comprises the following steps: dissolving welan gum in water under the condition of stirring, dripping solution prepared from 3-chloropropionic acid and a catalyst into the welan gum water solution, reacting for 1 to 6 h at normal pressure and 60 to 80 DEG under the condition of stirring, collecting the reaction liquid, pouring the reaction liquid in anhydrous ethyl alcohol to enable carboxyethyl welan gum to be separated, washing, drying, and smashing to obtain the carboxyethyl welan gum. According to the invention, carboxylic acid group is introduced to welan gum, so that the water dissolving speed of welan gum can be improved.

Description

technical field

[0001] The invention belongs to a method for modifying microbial polysaccharides, in particular to a method for modifying welan gum. Background technique

[0002] Welan gum is a high molecular polysaccharide biopolymer produced by fermentation of corn starch. Its main chain structure is composed of units of D-glucose, D-glucuronic acid, D-glucose and L-rhamnose, and the side chain is composed of single-chain L-mannose or single-chain L-rhamnose Composition, the molecular weight is as high as several million. Its structure is close to that of guar gum. In the structure of guar gum, D-mannose is the main chain, and the side chain is galactose. According to different origins, the molecular weight is distributed between 200,000 and 2 million.

[0003] Table 1. Welan Gum vs. Guar Gum Comparison

[0004]

[0005] Welan gum is one of the most promising microbial polysaccharides developed by Kelco in the United States in the 1980s after xanthan gum and gellan g...

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