Method for industrially producing high-purity walnut peptide from low-temperature pressed walnut meal as a raw material

Abstract

The invention discloses a method for industrially producing high-purity walnut peptide from low-temperature pressed walnut meal as a raw material. According to the method, cold pressed walnut meal istaken as a raw material, is dispersed and hydrated, and then is subjected to enzymolysis with tannase, cellulase and medium-temperature amylase; then, a product is denatured, step-by-step enzymolysisis performed with alkaline protease and neutral protease, enzyme deactivation is performed, centrifugation and plate and frame filtration are performed, and high-purity walnut peptide is obtained. industrial preparation of high-purity walnut peptide is realized economically by scientific optimization of pretreatment, enzymolysis and refining processes, the protein content is 90% or higher, the peptide content is 85% or higher, the relative molecular weight is lower than 2000 Dal, peptide accounts for 85% or higher, the relative molecular weight is lower than 1000 Dal and peptide accounts for50% or higher; the product has good quality and light bitterness, is easily mixed with other food ingredients, and has outstanding effects of strengthening the brain, improving intelligence and enhancing immunity. The walnut peptide can be used as a high-quality functional base material to be widely applied to various food and health products.

Description

technical field [0001] The invention belongs to the technical field of high value-added processing and utilization of agricultural and sideline products, and specifically relates to a method for industrially producing high-purity walnut peptides by using low-temperature pressed walnut meal as raw material. Background technique [0002] Walnut is one of the four major dried fruits in the world, and is loved by consumers at home and abroad because of its rich nutritional value. Contain 63~70% of fat (mainly unsaturated fatty acid, accounting for 90% of its total amount) in every 100 grams of walnut kernels, protein 15~29%, carbohydrate 15%; In addition, also contain calcium, phosphorus, iron, Zinc, magnesium, carotene, riboflavin, vitamin B6, vitamin E, juglone, phospholipids and other nutrients. China is one of the origins of walnuts, with a cultivation history of more than 2,000 years. At present, China's walnut cultivation area and output rank first in the world. However,...

AI Technical Summary

Problems solved by technology

The outstanding problems in the preparation of walnut peptide mainly include: (1) The product purity is low, that is, the protein content of walnut peptide is low, mainly because there is still a certain amount of starch and oil in the walnut meal, which cannot be pretreated before enzymatic hydrolysis and separated after enzymatic hydrolysis Effectively removed during refining, the final peptide product has a high content of non-protein components, which affects the quality of the product; (2) The walnut protein structure is dense, the enzymatic hydrolysis efficiency is low, and the low molecular weight peptide content in the enzymatic hydrolysis product is not high; (3) The walnut meal Contains walnut kernel skin, black color and bitter taste, if not effectively treated, it will affect the color and flavor of the product; (4) The preparation process is cumbersome, without scientific optimization, high cost, and difficult to implement industrially

For example, patent CN103109971B discloses that walnut pulp after cold pressing of walnuts is used as raw material, and a walnut peptide with high arginine content is obtained by refining, compound protease enzymatic hydrolysis, membrane filtration, concentration and drying, and the active peptide yield of this method is lower than 30%. %, the protein content of the product is low, and the molecular weight of the main peptide is less than or equal to 3000kD; patent CN 102630804A discloses a kind of degreased walnut meal as raw material, which is obtained by adding water to mix uniformly, homogeneously, compound enzyme enzymolysis, inactivating enzyme, centrifuging, and concentrating and drying. Walnut peptide powder, the product of this method has low protein content, wide range of peptide molecular weight, and low content of small molecule peptides; patent CN 103103244B discloses a preparation method of walnut blood pressure lowering peptide, using walnut meal as raw material, and purifying walnut by alkali-soluble acid precipitation method Protein, and then use microwave combined with ultrasonic treatment to moderately denature walnut protein to improve the efficiency of enzymatic hydrolysis. Adding B-cyclodextrin to entrapment and vacuum freeze-drying to obtain walnut hypotensive peptide, this method uses the traditional alkali-soluble acid precipitation method to process walnut meal, because of the special compactness of walnut protein structure, it is difficult to obtain ideal purity (protein content 90 %) walnut protein, in addition, denaturation treatment before enzymolysis and membrane separation after enzymolysis are too complicated, require high equipment, are not easy to industrialize, and the production cost of the product is high

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