Preparation method of culture medium suitable for xylose-rich xylitol zymolysis production

Abstract

The present present inventiondiscloses a culture matrix preparation method, which contains xylitol and is applied to xylitol fermentation production. The culture matrix is obtained from organic matters, which are rich in celluloses and hemicelluloses and are hydrolytically detoxified after the steps of drying, washing by acid, acidolysis, decoloration, electrodialysis, concentration, etc. The present present invention is scrubbed with weak acid before acidolysis, which makes the content of impurities reduced and the quality of acidolysis solution improved. A plurality of acid radical ions and harmful ions in the acidolysis solution can be eliminated by a method of the electrodialysis, which can make the back reverse osmosis membrane concentration keep a high flux. With the back reverse osmosis membrane concentration, the cost can be effectively reduced, but the throughput is large. The defect that a plurality of steam and energies is consumed in the traditional steam heating concentration is overcomed. And the method is applied to industrial production. The vacuum thermal concentration can be further implemented after the reverse osmosis membrane concentration, which can eliminate volatile harmful materials and is beneficial for the biological fermentation and the xylitol production.

Description

technical field [0001] The invention belongs to the field of microbial fermentation, and in particular relates to a preparation method of a culture substrate rich in xylose obtained from cheap agricultural by-products and suitable for fermenting and producing xylitol. Background technique [0002] Xylitol (molecular formula C 5 h 12 o 5 ) is a natural sweetener, the chemical name is "pentose", which is a five-carbon sugar and is a normal intermediate of carbohydrate metabolism in the human body. Xylitol integrates sweetener, nutrient, and therapeutic agent, and is widely used in industries such as national defense, medicine, chemical industry, daily chemical, paint, and food. At present, industrial scale production mainly adopts the chemical synthesis method of xylose hydrogenation, which requires high temperature, high pressure, flammable and explosive high-pressure hydrogen and a nickel catalyst that requires high purity of the solution. Capital construction investment...

AI Technical Summary

Problems solved by technology

However, if the pH is adjusted to about 10, the hydrolyzed xylose will be destroyed and a lot of solid waste will be generated.

Moreover, due to the use of milk of lime to neutralize the inorganic acid in the hydrolyzate, it is easy to generate a large amount of gypsum precipitation, especially when it is concentrated for the first time, the scaling in the heater is serious, and this scaling can only be removed by mechanical means. After the equipment has been in operation for several days, it has to be stopped for descaling, which reduces the utilization rate and service life of the equipment, and the steam consumption is also high, which increases the production cost

[0004] Ion exchange resin can effectively remove harmful ions in the hydrolyzate, and is a very good post-treatment method for the hydrolyzate. However, due to its high cost, people have been trying to replace it with a combination of the aforementioned methods.

In addition, some people have tried the method of extracting with ether after neutralization of milk of lime. This method is relatively expensive, and no other reports have been seen.