Extraction method of isolated vegetable protein

Abstract

The invention discloses an extraction method of isolated vegetable protein. The method comprises steps as follows: (1), vegetable meal after being degreased at a low temperature is soaked with an alcoholic solution; (2), after a mixed solution obtained in step (1) is subjected to solid-liquid separation, solid matter is obtained, and water is added to the solid matter for extraction; and (3), extract liquor obtained in step (2) is centrifuged, a protein solution is obtained, and the isolated vegetable protein is obtained after the protein solution is sterilized and dried. According to the extraction method of the isolated vegetable protein, pigments and various lipids in the vegetable meal can be removed by adopting an ethanol and water combination mode, so that a final product is free ofmixed color and has no fishy smell, and the obtained isolated vegetable protein has high protein content. Besides, the whole process is lower in water consumption, water is required to be added only in an extraction process, the water can be removed from the product by evaporation in a product drying process, no waste water is produced, and the method is environmentally friendly.

Description

technical field [0001] The invention relates to the field of food processing, in particular to a method for extracting plant protein isolate. Background technique [0002] A large amount of waste water will be generated in the traditional plant protein isolate production process, and the COD value of the waste water seriously exceeds the standard. The traditional plant protein extraction process has been included in the ranks of restricted development. Plant protein isolates obtained by traditional methods have problems such as poor taste and low protein content, which greatly limit the application of plant protein isolates in the food industry. [0003] Take soybean protein isolate as an example. Soybean contains 18-22% oil and about 40% protein. It is not only a major oil crop, but also a huge high-quality vegetable protein resource. Soybean protein isolate contains eight kinds of amino acids necessary for the human body, has low cholesterol content, and has certain adjuv...

AI Technical Summary

Problems solved by technology

This technique has the following problems: 1, the amount of waste water discharge is large: the total amount of water added is about 9-15 times that of low-temperature defatted soybean meal during the first extraction and the second extraction, and about 18-20% water (about 4m3) is arranged in the centrifugation process 3 / ton of finished product) is taken away by sediment (okara), mixed soymilk produces 70-80% of waste water in the process of acid precipitation and centrifugation, and the discharge of soy clear water, the total waste water discharge can reach 18-26m 3 / (tons of isolated soy protein), the solid content of these wastewaters is about 2-3%

Too much sodium intake will increase the possibility of high blood pressure, arteriosclerosis, heart disease and stroke. The daily intake of sodium for adults should be 1100-3300 mg, so the soybean protein isolate produced by traditional technology is added during the production process. Na+-containing lye, resulting in a high Na value in the final product, therefore, soy protein isolate products are limited in terms of healthy diet

3. The protein in the acid precipitation is in a hydrophobic environment, and there are many non-polar lipids, the main source of beany smell, plant pigments and trace plant-specific components will be adsorbed on the surface of the protein. Therefore, the "alkali-soluble acid precipitation" process is used to produce The isolated soybean protein is yellow in color and has a strong beany smell

[0005] Soybean protein concentrate (protein content ≤ 70.0%) process uses alcohol-soluble method to extract soluble components in low-temperature defatted soybean meal. The alcohol-soluble method extracts soluble oligosaccharides and other soluble components and does not remove insoluble components. Fiber (okara) is removed, therefore, soybean protein products also contain ≥ 20.0% insoluble fiber (okara,) resulting in protein content ≤ 70.0% in soybean protein concentrate products, product taste is poor, protein is insoluble in water, and the product is used in food applications Soybean protein concentrate is currently mainly used for feedstuffs. The current mainstream soy protein products in the market are still mainly isolated from soy protein (protein content ≥ 90.0%) obtained by alkali-dissolving and acid-precipitating processes.

Other plant protein isolates also have problems similar to soybean protein isolates, which limits the application of plant protein isolates

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