Application of food-borne polysaccharide in decoloration of hemoglobin and method for decoloration of hemoglobin by using food-borne polysaccharide

Abstract

The invention relates to the technical field of food chemistry, in particular to application of food-borne polysaccharide in hemoglobin decolorization and a method for decolorizing hemoglobin by using the food-borne polysaccharide. The invention discovers that pectin, xanthan gum or gellan gum can be used for decolorizing hemoglobin for the first time, the food-borne polysaccharide has the advantages of high efficiency and greenness when being used for decolorizing hemoglobin, and the complete structure and functional characteristics of protein can be retained. Dietary polysaccharide which can be used as a food additive is used as a decolorizing agent, organic reagents are not used, and the raw materials are low in cost, natural and harmless. The decolorizing process provided by the invention is simple in process flow, green and environment-friendly, high in production efficiency, free of special equipment and suitable for industrial large-scale production. Meanwhile, the protein decolorization rate in the protein solution obtained after decolorization by the method is as high as 94.95%, the protein recovery rate is as high as 90.55%, and the product can be applied to the food industry as a high-quality protein resource.

Description

Technical Field

[0001] The invention relates to the technical field of food chemistry, in particular to application of food-derived polysaccharides in decolorization of hemoglobin and a method for decolorizing hemoglobin using the food-derived polysaccharides. Background Art

[0002] my country is a major livestock and poultry breeding country, and its output ranks among the top in the world. In 2022, the number of major livestock exceeded 1.12 billion, and the number of poultry exceeded 11.83 billion. Blood accounts for about 6%-8% of the body weight of livestock and poultry. After removing about 80% of the water, most of the remaining substances are proteins, so it is a rich source of protein, mainly hemoglobin, which accounts for about 65% of the dry weight of blood. Therefore, the annual output of livestock and poultry blood in my country is estimated to be 11.2 million tons, and 1.57 million tons of hemoglobin can be produced each year. In addition to high yield, hemoglobin also has the advantage of a balanced amino acid ratio and is considered to be a high-quality protein resource. However, except for dishes such as blood tofu and black pudding, most of the blood is not eaten by humans, but used as animal feed or fertilizer, or even discarded on a large scale, wasting resources and polluting the environment if improperly handled. In the face of the global protein shortage, it is of great significance to use hemoglobin in food applications.

[0003] Hemoglobin faces two major challenges in food applications. One is the problem of too dark color, which is mainly caused by the heme group in hemoglobin. Color is an important sensory indicator of food. At present, foods made from blood make full use of the deep red color of hemoglobin, but in turn, it also limits its addition amount and application scenarios in food. The second limitation is the intake of heme. Hemoglobin is a tetramer with four polypeptide chains, and each chain is connected to a heme group. Therefore, the intake of hemoglobin is constrained by the upper limit of heme intake. Although heme has a wide range of biological functions, including oxygen transport, iron storage, and electron transfer, excessive intake will generate reactive oxygen species (ROS), leading to cell and tissue damage, which means that the intake of heme needs to be strictly controlled. If heme and decolorized hemoglobin can be separated and used as needed, the above problems can be solved.

[0004] The decolorization methods that have been developed so far, including organic reagent extraction, carboxymethyl cellulose adsorption, hydrogen peroxide oxidation and enzymatic hydrolysis, all have shortcomings, specifically manifested as follows:

[0005] 1. Organic reagent extraction is based on the solubility difference between heme and protein in acidified organic reagents (such as acetone), which may leave organic reagent residues in the extracted protein and the protein recovery rate is relatively low.

[0006] 2. Carboxymethyl cellulose adsorption is based on the difference in adsorption specificity of carboxymethyl cellulose to heme and protein to achieve separation. This method involves heating treatment, which may change the activity and structure of the protein.

[0007] 3. Hydrogen peroxide oxidation uses oxidants to cleave the porphyrin ring to achieve the purpose of degrading heme, but it may be accompanied by the oxidation of sulfur-containing amino acids, affecting the functionality of the protein. Therefore, hydrogen peroxide treatment conditions are harsh.

[0008] 4. Enzymatic hydrolysis uses proteases to decompose hemoglobin, exposing heme and detaching it from the polypeptide chain, thereby separating heme from protein. However, the decolorized hemoglobin obtained is a mixture of polypeptides of different molecular weights, not a protein with a complete structure, so that the original protein functional properties such as foaming and gelling properties are lost.

[0009] In summary, in order to avoid the problems existing in the existing process, it is necessary to develop an efficient, green hemoglobin decolorization method that retains the complete structure and functional properties of the protein. Summary of the invention

[0010] The purpose of the present invention is to provide an application of food-derived polysaccharides in decolorizing hemoglobin and a method for decolorizing hemoglobin using food-derived polysaccharides, so as to solve the problems existing in the above-mentioned prior art. The present invention first discovered that food-derived polysaccharides can be used for decolorizing hemoglobin, and decolorizing hemoglobin using food-derived polysaccharides has the advantages of high efficiency and greenness, and can also retain the complete structure and functional characteristics of the protein.

[0011] To achieve the above object, the present invention provides the following solutions:

[0012] The invention provides application of food-derived polysaccharide in decolorization of hemoglobin. The food-derived polysaccharide is pectin, xanthan gum or gellan gum.

[0013] Preferably, the hemoglobin is bovine hemoglobin or porcine hemoglobin.

[0014] Further preferably, the gellan gum includes low acyl gellan gum and high acyl gellan gum.

[0015] The invention provides application of food-derived polysaccharide in preparing a hemoglobin decolorizing agent. The food-derived polysaccharide is pectin, xanthan gum or gellan gum.

[0016] Preferably, the hemoglobin is bovine hemoglobin or porcine hemoglobin.

[0017] Further preferably, the present invention provides a hemoglobin decolorizing agent, wherein the hemoglobin decolorizing agent is a food-derived polysaccharide and an auxiliary material.

[0018] Further preferably, the food-derived polysaccharide is pectin, xanthan gum or gellan gum; and the hemoglobin is bovine hemoglobin or porcine hemoglobin.

[0019] The present invention provides an efficient and green method for decolorizing hemoglobin using food-derived polysaccharides, comprising the following steps:

[0020] mixing the hemoglobin solution and the food-derived polysaccharide solution to obtain a protein-polysaccharide mixed solution;

[0021] The pH of the protein-polysaccharide mixed solution is adjusted, stirred, allowed to stand and centrifuged in sequence to obtain a decolorized protein solution.

[0022] Preferably, the mass ratio of hemoglobin to food-derived polysaccharide in the protein-polysaccharide mixed solution is (1-2):1.

[0023] Preferably, the hemoglobin is bovine hemoglobin; and the food-derived polysaccharide is pectin, xanthan gum or gellan gum.

[0024] Preferably, the pH regulator used to adjust the pH is a 1-5M HCl solution;

[0025] The pH of the solution obtained after the pH adjustment is 2.0.

[0026] Preferably, the centrifugal condition parameters are: centrifugation at 10000 g for 20 min.

[0027] Preferably, the stirring time is 30 minutes; the standing time is 5 minutes.

[0028] The present invention discloses the following technical effects:

[0029] (1) The present invention uses dietary polysaccharides that can be used as food additives as decolorizing agents, does not use organic reagents, and has low raw material costs and is natural and harmless.

[0030] (2) The process of the present invention is simple, environmentally friendly, and has high production efficiency. It does not require special equipment and is suitable for industrial large-scale production.

[0031] (3) After decolorization by the method of the present invention, the protein decolorization rate in the obtained protein solution is as high as 94.95%, and the protein recovery rate is as high as 90.55%. The product can be used as a high-quality protein resource in the food industry.

[0032] (4) The present invention also produces a high value-added by-product rich in heme, which can be further utilized.

[0033] (5) The present invention first discovered that pectin, xanthan gum or gellan gum can be used to decolorize hemoglobin. Decolorizing hemoglobin using food-derived polysaccharides has the advantages of being efficient and green, and can also retain the complete structure and functional characteristics of the protein.Figure 3 In the electrophoresis diagram, the protein band after decolorization is similar to the original hemoglobin, and the molecular weight has not changed significantly, indicating that the decolorization conditions will not cause protein hydrolysis, further indicating that the protein structure after decolorization is intact. Figure 5 The foaming properties of decolorized hemoglobin are compared with those of undecolorized hemoglobin. After foaming, the foam height of decolorized hemoglobin is higher than that of undecolorized hemoglobin under neutral (pH=7) conditions, and after 2 hours, the foam stability of decolorized hemoglobin is also stronger than that of undecolorized hemoglobin. Therefore, the decolorization process does not weaken the foaming functional properties of hemoglobin.

[0034] In summary, the method of decolorizing hemoglobin using food-derived polysaccharides of the present invention has a simple process flow, does not require special equipment, and is suitable for industrial production. The decolorized hemoglobin can be used as a high-value protein resource in the food field, which has an important impact on the food field. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 A comparison chart of the product and raw material obtained by the method provided by the present invention;

[0037] Figure 2 Flow chart for decolorization of hemoglobin using food-derived polysaccharides;

[0038] Figure 3 The following is a comparison of the appearance of hemoglobin before and after decolorization using food-derived polysaccharides; A is a macroscopic image of the supernatant after decolorization; B is an SDS-PAGE image; the ratio is the mass ratio of the food-derived polysaccharide solution to the hemoglobin solution;

[0039] Figure 4 The figure is a diagram showing the effect of using food-derived polysaccharides to decolorize hemoglobin; A is the decolorization rate of different polysaccharides; B is the protein recovery rate; and the ratio is the mass ratio of the food-derived polysaccharide solution to the hemoglobin solution;

[0040] Figure 5 The figure is a comparison chart of the foaming ability of decolorized hemoglobin and non-decolorized hemoglobin under neutral conditions (pH=7); wherein A is the solution after foaming, and the number indicates the foam height; B is the foam height at 0h and 2h after foaming, and the number indicates the foam stability. DETAILED DESCRIPTION

[0041] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0042] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0043] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0044] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0045] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0046] The determination steps of decolorization rate in the present invention are described as follows:

[0047] 1. Prepare the hemin chloride standard solution: weigh 0.1g of hemin chloride powder into a sample bottle, add 5mL of 1M NaOH solution, and gently shake the sample bottle to dissolve the hemin chloride. Then, add 95mL of Milli-Q water and stir well to prepare a 1mg / mL hemin chloride standard solution.

[0048] 2. Determine the absorption wavelength: At different pH values, the absorption curves of heme and hemoglobin are significantly different. Only under alkaline conditions (pH = 12) are the absorption peaks of the two similar, at 385nm. Therefore, the heme concentration in the sample solution is measured based on the absorbance value at 385nm at pH = 12.

[0049] 3. Determination of hemoglobin standard curve: dilute the hemoglobin standard solution to 0.1, 0.08, 0.06, 0.04, 0.02, 0.01, 0.005 mg / mL, measure the absorbance of each concentration of hemoglobin standard solution at 385nm, use this as the ordinate and the concentration of the hemoglobin standard solution as the abscissa, perform linear regression, and establish a standard curve of absorbance at 385nm and hemoglobin content. The standard curve equation is y=85.635x, and the correlation coefficient is R 2 =0.9993.

[0050] 4. Determine the hemoglobin concentration of the sample: adjust the pH of the sample solution to 12, measure the absorbance of the sample solution at 385nm, and calculate the hemoglobin concentration of the sample from the standard curve.

[0051] 5. The calculation formula of decolorization rate is as follows:

[0052]

[0053] Wherein, DR (%) is the decolorization rate, n is the number of heme molecules bound to each protein molecule in the initial hemoglobin solution (n=3.20 measured in the present invention), C1 is the protein concentration of the supernatant after decolorization using polysaccharide (mg / mL), C2 is the heme concentration of the supernatant after decolorization using polysaccharide (mg / mL), M2 is the molecular weight of hemin (M2=652g / mol), and M1 is the molecular weight of hemoglobin (M1=64500g / mol).

[0054] The steps for determining the protein recovery rate in the present invention are described as follows:

[0055] 1. Determine the protein concentration of the sample: Use the BCA method to determine the protein concentration in the sample solution.

[0056] 2. The calculation formula of protein recovery rate is as follows:

[0057]

[0058] Wherein, PR (%) is the protein recovery rate, C0 and C1 are the protein concentrations (mg / mL) of the initial hemoglobin solution and the supernatant after decolorization with polysaccharide, respectively, and V0 and V1 are the volumes (mL) of the initial hemoglobin solution and the supernatant after decolorization with polysaccharide, respectively.

[0059] The present invention is further described in detail below in conjunction with specific embodiments. The following embodiments belong to a part of the present invention and cannot limit the protection scope of the present invention.

[0060] Experimental Example 1

[0061] A method for decolorizing hemoglobin using food-derived polysaccharides, the process is as follows Figure 2 As shown, the specific steps are as follows:

[0062] A 2.5 mg / mL hemoglobin solution and a 10 mg / mL food-derived polysaccharide solution were prepared, wherein the food-derived polysaccharide was one of pectin, xanthan gum, low acyl gellan gum and high acyl gellan gum.

[0063] 16 mL of hemoglobin solution was mixed with 4, 2, 1 and 0.5 mL of polysaccharide solution, respectively, and made up to 20 mL with deionized water. The two were mixed so that the mass ratios of food-derived polysaccharides and hemoglobin in the resulting mixed solution were 1:1, 1:2, 1:4 and 1:8. The pH of the mixed solution was then adjusted to 2.0 with 5 M HCl, stirred at room temperature for 30 min, allowed to stand for 5 min, and centrifuged at 10,000 g for 20 min. The supernatant was collected to obtain a decolorized hemoglobin solution. The supernatant was arranged according to the initial hemoglobin solution and polysaccharide / protein mass ratios of 1:1, 1:2, 1:4, and 1:8, and the supernatant was subjected to electrophoresis analysis. The results are as follows: Figure 3 As shown. Figure 3 It can be seen that the four polysaccharides and proteins showed significant decolorization effects at mass ratios of 1:1 and 1:2, that is, the color of the supernatant became significantly lighter, close to colorless, and the width of the corresponding electrophoresis band was not significantly different from that of the initial protein solution, indicating that most of the protein was recovered at the same time.

[0064] In addition, the decolorization rate and protein recovery rate were further investigated, and the experimental results are shown in Tables 1 to 7.

[0065] Table 1 Protein concentration (C1) of the supernatant after polysaccharide decolorization in different treatments

[0066]

[0067] Table 2 Absorbance values ​​at 385 nm in different treatments

[0068]

[0069] Table 3 Heme concentration (C2) of the supernatant after polysaccharide decolorization in different treatments

[0070]

[0071]

[0072] Table 4 Protein concentration (C0) of initial hemoglobin solution in different treatments

[0073]

[0074] Table 5 Volume of initial hemoglobin solution (V0) and volume of supernatant after decolorization with polysaccharide (V1) in different treatments

[0075]

[0076] Note: Since the volume of the supernatant after decolorization with polysaccharide is above 19.8 mL, the table shows 20 mL.

[0077] Table 6 Decolorization rate in different treatments (%)

[0078]

[0079] Table 7 Protein recovery rate in different treatments (%)

[0080]

[0081] As shown in Tables 1 and 7, the four polysaccharides and proteins all showed significant decolorization effects at mass ratios of 1:1 and 1:2, and also had a high protein recovery rate.

[0082] Example 2

[0083] A method for decolorizing hemoglobin using food-derived polysaccharides, the specific steps are as follows:

[0084] Weigh 200 mg of bovine hemoglobin and 100 mg of food-derived polysaccharide (one of pectin, xanthan gum, low acyl gellan gum and high acyl gellan gum) and dissolve them in 80 mL and 10 mL of deionized water respectively to prepare a hemoglobin solution with a concentration of 2.5 mg / mL and a food-derived polysaccharide with a concentration of 10 mg / mL. After mixing the two, the mass ratio of food-derived polysaccharide to hemoglobin in the obtained mixed solution is 1:1 and 1:2; then adjust the pH of the mixed solution to 2.0 with 5M HCl, stir at room temperature for 30 minutes, stand for 5 minutes, centrifuge at 10000g for 20 minutes, collect the supernatant, and obtain a decolorized hemoglobin solution. The decolorization effect is quantitatively characterized by the above-mentioned decolorization rate and protein recovery rate determination steps. The results are as follows: Figure 4 As shown. Figure 4 It can be seen that under the conditions of mass ratio of 1:1 and 1:2, the decolorization rate of the four polysaccharides can reach more than 90%, with the highest being 95.06%; and at least 50% of the protein is recovered, with the highest being 87.78%. Among them, gellan gum can achieve a decolorization rate and protein recovery rate of about 90% at the same time.

[0085] Example 3

[0086] A method for decolorizing hemoglobin using food-derived polysaccharides, the specific steps are as follows:

[0087] A 40 mg / mL hemoglobin solution and a 40 mg / mL food-derived polysaccharide solution were prepared, wherein the food-derived polysaccharide was one of pectin, xanthan gum and low-acyl gellan gum.

[0088] 10 mL of hemoglobin solution was mixed with 10 and 5 mL of food-derived polysaccharide solution, respectively, and filled to 20 mL with deionized water, so that the mass ratio of polysaccharide to hemoglobin in the obtained mixed solution was 1:1 and 1:2. Then, the pH of the mixed solution was adjusted to 2.0 with 5M HCl, stirred at room temperature for 30 minutes, and centrifuged at 10000g for 20 minutes after standing for 5 minutes, and the supernatant was collected to obtain a decolorized hemoglobin solution. The decolorization rate and protein recovery rate were then investigated, and the experimental results are shown in Tables 8 to 14.

[0089] Table 8 Protein concentration of the supernatant after decolorization of polysaccharides in different treatments (C1)

[0090]

[0091] Table 9 Absorbance at 385nm in different treatments

[0092]

[0093] Table 10 Heme concentration (C2) of the supernatant after polysaccharide decolorization in different treatments

[0094]

[0095]

[0096] Table 11 Protein concentration (C0) of initial hemoglobin solution in different treatments

[0097]

[0098] Table 12 Volume of initial hemoglobin solution (V0) and volume of supernatant after decolorization with polysaccharide (V1) in different treatments

[0099]

[0100] Table 13 Decolorization rate (%) and protein recovery rate (%) in different treatments

[0101]

[0102] Table 14 Protein recovery rate in different treatments (%)

[0103]

[0104] It can be seen from Tables 6, 7 and 13, 14 that in the case of high-concentration polysaccharide solutions, the three polysaccharides and hemoglobin have similar decolorization effects at a mass ratio of 1:1 as at low concentrations. In addition, the decolorization effect of pectin and hemoglobin at a mass ratio of 1:2 is similar to that at low concentrations.

[0105] Example 4

[0106] A method for decolorizing hemoglobin using food-derived polysaccharides, the specific steps are as follows:

[0107] Weigh 200 mg of bovine hemoglobin and 200 mg of pectin and dissolve them in 80 mL and 20 mL of deionized water, respectively, to prepare a hemoglobin solution with a concentration of 2.5 mg / mL and a pectin solution with a concentration of 10 mg / mL. Mix the two so that the mass ratio of hemoglobin to pectin in the obtained mixed solution is 1:1; then adjust the pH of the mixed solution to 2.0 with 5M HCl, stir at room temperature for 30 minutes, stand for 5 minutes, centrifuge at 10000g for 20 minutes, collect the supernatant, and obtain a decolorized hemoglobin solution. The precipitate after centrifugation is a byproduct rich in heme, which can be redissolved in an alkaline aqueous solution. The obtained protein solution was freeze-dried at -50℃ for 3 days to obtain a decolorized hemoglobin solid powder. The decolorization rate and protein recovery rate were then investigated. The results showed that the decolorization rate was 95.06% and the protein recovery rate was 74.58%.

[0108] Example 5

[0109] A method for decolorizing hemoglobin using food-derived polysaccharides, the specific steps are as follows:

[0110] Weigh 200 mg of bovine hemoglobin and 100 mg of low acyl gellan gum and dissolve them in 80 mL and 20 mL of deionized water, respectively, to prepare a hemoglobin solution with a concentration of 2.5 mg / mL and a gellan gum solution with a concentration of 5 mg / mL. Mix the two so that the mass ratio of low acyl gellan gum to hemoglobin in the obtained mixed solution is 1:2; then adjust the pH of the mixed solution to 2.0 with 5M HCl, stir at room temperature for 30 minutes, stand for 5 minutes, centrifuge at 10000g for 20 minutes, collect the supernatant, and obtain a decolorized hemoglobin solution. The obtained protein solution was freeze-dried at -50℃ for 3 days to obtain a decolorized hemoglobin solid powder. The decolorization rate and protein recovery rate were then investigated. The results showed that the decolorization rate was 91.30% and the protein recovery rate was 87.78%.

[0111] Example 6

[0112] A method for decolorizing hemoglobin using food-derived polysaccharides, the specific steps are as follows:

[0113] Weigh 200 mg of bovine hemoglobin and 200 mg of xanthan gum and dissolve them in 80 mL and 20 mL of deionized water, respectively, to prepare a hemoglobin solution with a concentration of 2.5 mg / mL and a xanthan gum solution with a concentration of 10 mg / mL. Mix the two so that the mass ratio of hemoglobin to xanthan gum in the obtained mixed solution is 1:1; then adjust the pH of the mixed solution to 2.0 with 5M HCl, stir at room temperature for 30 minutes, stand for 5 minutes, centrifuge at 10000g for 20 minutes, collect the supernatant, and obtain a decolorized hemoglobin solution. The obtained protein solution was freeze-dried at -50℃ for 3 days to obtain a decolorized hemoglobin solid powder. The decolorization rate and protein recovery rate were then investigated. The results showed that the decolorization rate was 91.76% and the protein recovery rate was 54.89%.

[0114] Example 7

[0115] A method for decolorizing hemoglobin using food-derived polysaccharides, the specific steps are as follows:

[0116] Weigh 2g bovine hemoglobin and 1g pectin and dissolve them in 50mL and 50mL deionized water respectively to prepare a hemoglobin solution with a concentration of 40mg / mL and a pectin solution with a concentration of 20mg / mL. Mix the two so that the mass ratio of pectin to hemoglobin in the obtained mixed solution is 1:2; then adjust the pH of the mixed solution to 2.0 with 5M HCl, stir at room temperature for 30min, stand for 5min, centrifuge at 10000g for 20min, collect the supernatant, and obtain a decolorized hemoglobin solution. The obtained protein solution was freeze-dried at -50℃ for 3 days to obtain a decolorized hemoglobin solid powder. The decolorization rate and protein recovery rate were then investigated. The results showed that the decolorization rate was 91.88% and the protein recovery rate was 78.06%.

[0117] Experimental Example 8

[0118] The decolorized hemoglobin solid powder obtained in Example 7 was compared with the raw material and commercially available hemoglobin. The results are as follows: Figure 1 (Raw material comparison chart) as shown. Figure 1 It can be seen that the decolorized hemoglobin product is light yellow, which is much lighter in color than the dark red raw material.

[0119] Example 9

[0120] The decolorized hemoglobin solid powder obtained in Example 8 was dissolved in deionized water to prepare 5 mL of 2 mg / mL decolorized hemoglobin solution. The pH of the solution was adjusted to 7.0 with 0.5 M NaOH. The solution was stirred at 10000 rpm for 2 min at room temperature with a homogenizer at the same time as the undecolorized hemoglobin solution under the same conditions. The foam height at this time and the foam height after standing for 2 hours were recorded. The foaming property was represented by the foam height of the original solution per unit height in a container of the same inner diameter, and the foam stability was represented by the ratio of the foam height after 2 hours to that at 0 hours. The specific formula is as follows.

[0121]

[0122] Wherein, FA (%) is the foaming property, FS (%) is the foam stability, H0 is the height of the solution without foaming (cm), H1 is the foam height of the solution after foaming (cm), and H2 is the foam height of the solution after standing for 2 hours (cm).

[0123] The foaming ability comparison results are as follows Figure 5 As shown. The results show that after foaming, the foam height of decolorized hemoglobin is higher than that of undecolorized hemoglobin under neutral (pH=7) conditions, and after 2 hours, the foam stability of decolorized hemoglobin is also stronger than that of undecolorized hemoglobin. Therefore, the decolorization process will not weaken the foaming function of hemoglobin. It can be seen that the foaming property and foam stability of decolorized hemoglobin are stronger than those of undecolorized hemoglobin.

[0124] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. The use of food-derived polysaccharides in decolorizing hemoglobin is characterized in that: The food-derived polysaccharide is pectin, xanthan gum or gellan gum.

2. The use according to claim 1, characterized in that: The hemoglobin is bovine hemoglobin or porcine hemoglobin.

3. The use of food-derived polysaccharides in the preparation of a hemoglobin decolorizing agent, characterized in that: The food-derived polysaccharide is pectin, xanthan gum or gellan gum.

4. The use according to claim 3, characterized in that: The hemoglobin is bovine hemoglobin or porcine hemoglobin.

5. An efficient and green method for decolorizing hemoglobin using food-derived polysaccharides, characterized in that: The following steps are involved: mixing the hemoglobin solution and the food-derived polysaccharide solution to obtain a protein-polysaccharide mixed solution; The pH of the protein-polysaccharide mixed solution is adjusted, stirred, allowed to stand and centrifuged in sequence to obtain a decolorized protein solution.

6. The method according to claim 5, characterized in that The mass ratio of hemoglobin to food-derived polysaccharide in the protein-polysaccharide mixed solution is (1-2):

1.

7. The method according to claim 5, characterized in that The food-derived polysaccharide is pectin, xanthan gum or gellan gum; the hemoglobin is bovine hemoglobin or porcine hemoglobin.

8. The method according to claim 5, characterized in that The pH regulator used to adjust the pH is 1-5M HCl solution; The pH of the solution obtained after the pH adjustment is 2.

0.

9. The method according to claim 5, characterized in that The centrifugal condition parameters are: centrifugation at 10000 g for 20 min.

10. The method according to claim 5, characterized in that The stirring time is 30 min; the standing time is 5 min.

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