A method for determining the concentration of water-soluble peanut protein in a solution containing reducing monosaccharides

Abstract

The invention discloses a method for measuring the concentration of water-soluble peanut protein in a solution containing reducing monosaccharides, which comprises the following steps: (1) using acetonitrile to pretreat the sample; (3) after color development, measure the molar absorptivity of various reducing monosaccharides at 562nm and the total absorbance value of the sample to be tested at this wavelength by ultraviolet-visible spectroscopy; (4) based on the above steps Determination of parameter values, while taking bovine serum albumin as a reference standard for peanut protein, deducting the contribution of reducing monosaccharides to the total absorbance value at 562nm wavelength, and calculating the concentration of water-soluble peanut protein in the sample obtained from the pretreatment. The invention eliminates the interference of different reducing monosaccharides in the sample on the determination of the water-soluble peanut protein concentration, and the experimental results show that the high rate of the water-soluble peanut protein concentration caused by the reducing monosaccharide reaches 22%-50%.

Description

technical field [0001] The invention belongs to the technical field of chemical detection, in particular to a method for measuring the concentration of water-soluble peanut protein in a solution containing reducing monosaccharides. Background technique [0002] Peanut is one of the six important raw materials for cooking oil in China. At present, my country's annual peanut production ranks first in the world, accounting for more than 40% of the world's total peanut production. In addition to being used for food, export and crop seeds, about 50-60% of peanuts are used to prepare edible oil every year. The residue after peanuts are pressed to produce oil is called peanut meal, and its annual output has reached more than 3 million tons. In addition to carbohydrates and a small amount of fatty substances, the protein content in peanut meal is as high as more than 50%. After effective extraction, purification and refining, peanut protein can be directly used as a natural addit...

AI Technical Summary

Problems solved by technology

Therefore, according to the method of the published invention patent (Application No.: 201710213757.2), first, due to the different molar absorptivity coefficients at specific wavelengths after the color reaction of glucose and cellobiose with DNS, the reducing sugar in the sample measured by the DNS method The concentration itself is inaccurate; secondly, due to the large difference in the molar absorptivity at a specific wavelength after the color reaction of glucose and xylose with the BCA reagent, glucose is used as a standard to measure reducing sugars (including different monosaccharides) at specific wavelengths. Molar absorptivity coefficient, and then according to the concentration of reducing sugar measured by DNS method to calculate the accuracy of the interference of reducing sugar on the total absorbance value of the sample is even less accurate

In general, the published invention patent (application number: 201710213757.2) has the following significant deficiencies: (1) the concentration of reducing sugar measured by the DNS method is inaccurate; (2) after the color reaction with the BCA reagent, different monosaccharides (such as glucose and xylose) at specific wavelengths for large differences in molar absorptivity

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