Method for extracting substances from fermented shrimp head shells

Abstract

The invention relates to a method for extracting astaxanthin, protein, calcium lactate and chitin from shrimp heads through microbes. A supernatant fluid and a solid precipitate are respectively collected by centrifugation after fermentation treatment is performed on the shrimp head shells by utilizing streptococcus thermophilus under proper conditions. The solid precipitate is soaked in ethanol and then centrifugated, and the liquid part is evaporated for recovering an organic solvent so as to get the astaxanthin; the residual solid part is dried to get a chitin crude product; and the centrifugated supernatant fluid is subjected to spray-drying and concentration so as to get composite protein peptide powder which is rich in the calcium lactate and amino acids. The process has the advantages of reasonable process, no pollution, complete utilization of raw materials, high product quality and the like.

Description

technical field [0001] The invention relates to the technical field of extracting astaxanthin, protein, calcium lactate and chitin from shrimp heads by using microbial fermentation technology. Background technique [0002] Astaxanthin, the full name is 3,3'-dihydroxy-β-carotene-4,4'-ketone, which belongs to ketone carotenoids, is bright red, fat-soluble, and has high-efficiency anti-oxidation, anti-cancer, enhances Functions such as immunity and coloring. Due to the optical activity of the hydroxyl groups (-OH) at both ends, astaxanthin has three isomers: 3S-3'S, 3R-3'S, 3R-3'R (also known as left-handed, racemic, and right-handed). form. The latest pharmacological and physiological studies have found that astaxanthin has strong biological antioxidant properties and has been widely used in food, medicine, cosmetics and feed industries. A number of human and animal experiments have confirmed that natural astaxanthin is absolutely safe for humans and animals. [0003] At p...

AI Technical Summary

Problems solved by technology

In addition, although yeast cells reproduce fast and have high biomass, the content of astaxanthin in the cells is low. In order to increase the production of astaxanthin, a large amount of carbon and nitrogen sources, especially organic nitrogen sources with high prices (yeast extract and peptone) need to be increased. etc.), it is easy to cause waste, increase the cost, and is not conducive to commercial production

[0006] (3) Algae: Although astaxanthin derived from algae has a 100% left-handed (3S-3'S) structure and has the strongest biological activity, the currently known microalgae usually grow slowly and require more Long autotrophic culture cycle, low biomass, harsh growth conditions, high requirements for water quality, environment and light, and large-scale production is still difficult

[0007] (4) Crustaceans: In nature, astaxanthin mainly exists in the shell of aquatic animals (such as shrimp and crab) in a large amount in the form of ester. Although the content is low, the ash and protein in the shell also limit astaxanthin. However, since no better method has been found at present, and the domestic and foreign aquatic product processing industries have 10 million tons of crustacean waste every year, which is rich in resources, the way of extracting natural astaxanthin from shrimp shells abroad still exists

However, the method used in the patent has deficiencies: (1) The fermenting microorganism used is the gram-negative bacillus Pseudomonas bacilli, which is an opportunistic pathogenic bacteria and will affect product safety

(2) The fermentation temperature is 37°C, which is the optimum growth temperature for pathogenic bacteria such as Escherichia coli, and it is very easy to infect bacteria and contaminate the fermented products

(3) This experiment requires sterilization of the shrimp head before fermentation, which will not only increase the cost, but also inactivate the endogenous enzymes in the shrimp head, affecting the hydrolysis efficiency

(4) Its fermentation process needs to pass oxygen, has increased production cost, is unfavorable for large-scale production

(5) The pH of the fermentation process of Pseudomonas is high, and the calcium in the carapace cannot be effectively recovered