A kind of preparation method of monascus yellow pigment

Abstract

The invention provides a preparation method of a monascus yellow pigment, comprising the following steps: sulfonating: performing a sulfonation reaction by taking an ethanol-soluble monascus red pigment as a raw material, dilute sulphuric acid as a sulfonating agent and sulfamic acid as an assistant; collecting sediment: collecting the obtained sediment, washing by using dilute alkali or water, and collecting the washed sediment; alkaline hydrolysis: adding an alkaline hydrolysis agent in the washed sediment for alkaline hydrolysis, thus obtaining monascus yellow conversion liquid; desalting: adjusting pH of the obtained monascus yellow conversion liquid, and desalting by using an electric drive film method, thus obtaining monascus yellow low-salt liquid; dying: concentrating and drying the obtained monascus yellow low-salt liquid, thus obtaining the monascus yellow pigment. The preparation method belongs to the technical field of pigments; by adding the small amount of sulfamic acid as the assistant, quick sulfonation of the dilute sulphuric acid on the ethanol-soluble monascus red pigment can be realized, reaction conditions are mild, by products are few, operation safety is good, and the prepared monascus yellow pigment is high in color value, good in stability and high in mass yield.

Description

technical field [0001] The invention belongs to the field of biotechnology, in particular to a preparation method of monascus yellow pigment. Background technique [0002] Monascus pigment is a metabolite secreted during the growth and metabolism of Monascus. It has the advantages of good stability, good coloring, and good safety, and has been widely used in the food field. The main components of alcohol-soluble monascus red pigment are erythematin and monascus red pigment, and its molecular structure is: [0003] The coloring of alcohol-soluble monascus red pigment is red, but its application is limited to a certain extent due to its poor solubility in water. Yellow pigment is one of the main varieties of food coloring. Water-soluble monascus yellow pigment can be obtained from alcohol-soluble monascus red pigment through sulfonation and other reactions. [0004] The paper entitled "Preparation of Water-Soluble Monascus Yellow Pigment" published by Su Jinwei et al. disc...

AI Technical Summary

Problems solved by technology

[0006] Although the existing technology can realize the preparation of water-soluble monascus yellow pigment, there are harsh reaction conditions, many by-products, the use of concentrated sulfuric acid or oleum, which is not conducive to safe operation, and with the progress of the reaction and the generation of water , the reaction speed is slowed down, there is no desalination step, the ash content in the final product is high, and it is difficult to meet the national health standards and other shortcomings