Process of extracting lactic streptocin from fermented liquid

Abstract

The process of extracting lactic streptocin from fermented liquid has one four-stage filtering process including the first stage of sheet frame filtering to eliminate the culture medium grain and great amount of thallus from the fermented liquid, the second stage of micro filtering to eliminate the residual thallus and partial macro molecular hetero protein, the third stage of ultrafiltering with 1,000-5,000 dalton ultrafiltering membrane to eliminate water, inorganic salt, amino acid and small molecular weight organic matter, and the fourth stage of ultrafiltering with 10,000-50,000 dalton ultrafiltering membrane to eliminate hetero protein of molecular weight over 7,000 dalton, pigment and macromolecular impurity, and the subsequent crystallizing and drying to obtain powdered product. The process has the advantages of no pollution, high product quality, low cost, high yield and other advantages.

Description

technical field [0001] The invention relates to a method for extracting food preservatives, in particular to a method for extracting nisin from fermentation broth. Background technique [0002] Preservatives are one of the most important additives in the food industry. Food preservatives are generally divided into synthetic preservatives and natural preservatives. After long-term research, it is found that the use of chemical preservatives mainly has the following problems: (1) There are few types of food preservatives, which cannot meet people's growing demand for food diversity; (2) Traditional preservatives are mainly acidic preservatives Mainly, it can only play a role under low pH conditions, and cannot play a role under neutral or weakly alkaline conditions, resulting in a very limited range of applications; (3) long-term use of these preservatives, some food spoilage bacteria have Drug resistance is produced, and the addition amount according to the national food add...

AI Technical Summary

Problems solved by technology

After long-term research, it is found that the use of chemical preservatives mainly has the following problems: (1) There are few types of food preservatives, which cannot meet people's growing demand for food diversity; (2) Traditional preservatives are mainly acidic preservatives Mainly, it can only play a role under low pH conditions, and cannot play a role under neutral or weakly alkaline conditions, resulting in a very limited range of applications; (3) long-term use of these preservatives, some food spoilage bacteria have Drug resistance is produced, and the amount added according to the national food additive hygiene standard can no longer achieve the expected antiseptic purpose, so that quality accidents with excessive preservatives frequently occur

[0014] The organic solvent extraction method requires low temperature operation and high energy consumption. The addition of organic solvents may inactivate nisin and increase the difficulty of post-treatment; while the solid particle adsorbent adsorbs nisin, it also adsorbs the pigment and peptides, the product appearance and purity are difficult to improve; the plate-and-frame filtration method requires a large amount of filter aids, the operation intensity is high, the equipment occupies a large area, and the operation time is long; while the ultrafiltration membrane concentrates nisin, it also concentrates pigments and peptides , there is also the problem that the appearance and purity of the product are difficult to improve