Method for extracting low-ash cereal pectin

Abstract

The application provides an extraction method of low-ash pectin of hemp, in particular, an extraction method of pectin of kenaf, sisal or ramie, which sequentially subjects the kenaf, sisal or ramie raw material to pretreatment, deashing treatment, acid extraction of pectin, adsorption of pigment, alcohol precipitation and filtration, washing and drying, to obtain a low-ash pectin product; through the method, high-quality low-ash pectin can be obtained with high yield; and the raw material source of the pectin is expanded, and a new idea is provided for comprehensive utilization of the kenaf, sisal and ramie.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of pectin extraction, and more particularly to a method for extracting low-ash pectin from flax. BACKGROUND

[0002] Pectin is a polysaccharide, which has two types of homogeneous polysaccharide and heteropolysaccharide. They are mostly present in plant cell walls and inner layers, and are abundant in the peels of citrus, lemon, grapefruit, etc. They are white to yellow powders, have a relative molecular mass of about 20-400 kDa, and are tasteless. Generally, pectin in plant cells can be divided into three types of protopectin, pectin and pectic acid. Among them, pectin is mainly formed by more than 75% of methyl esterified polygalacturonic acid chains, and the pectin is soluble in water; pectic acid is a straight-chain polymer formed by D-galacturonic acid through dehydration condensation and then connected by a-1, 4 glycosidic bond. Protopectin is mainly composed of homogalacturonan regions and rhamnogalacturonan scaffolds with neutral sugar side chains, and protopectin exists in the form of water-insoluble, which can form pectin and pectic acid after limited enzyme hydrolysis. The chemical structure of pectin is a polysaccharide formed by rhamnose and multiple galacturonic acids as the main chain, and then composed of side chains of different lengths of xylose, D-galactose and L-arabinose, etc. It is more stable in acidic solution than in alkaline solution, and is usually divided into high-ester pectin and low-ester pectin according to its esterification degree. High-ester pectin forms non-reversible gel in the range of soluble sugar content ≥ 60%, pH 2.6-3.4. Part of the methyl ester of low-ester pectin is converted into primary amide, which is not affected by sugar and acid, but needs to be combined with divalent ions such as calcium and magnesium to form gel. At present, the extraction methods of pectin mainly include water extraction, acid method, alkali method and chelation method, etc. Among them, water extraction can only extract some pectin that is easily soluble in water, and a large amount of water-insoluble pectin will be wasted.

[0003] The application field of pectin is particularly wide, and in the food industry, it can usually be used as a gelling agent, an emulsifying agent, a stabilizer and a thickening agent. At present, the raw materials of pectin mainly come from fruits (citrus, apples, etc.), vegetables (carrots, pumpkins, etc.) and other plant parts (such as flaxseed hulls, etc.).

[0004] Flax crops are one of the important sources of natural fibers. In addition to a large amount of cellulose fibers, flax crop bast raw materials also contain pectin, hemicellulose, lignin and other gum components. At present, extensive research has been conducted on the degumming of flax crop bast raw materials at home and abroad, and significant progress has been made.

[0005] However, the traditional processing method of hemp crops mainly obtains textile fiber raw materials, and the pectin contained therein is usually degraded during degumming and discharged with sewage, which not only causes waste of pectin resources, but also pollutes the environment, becoming a major challenge faced by hemp processing enterprises. In order to solve this problem, the research focus has gradually shifted to the extraction of bast pectin from hemp crops at home and abroad.

[0006] At present, the extraction technology of hemp crop pectin has made certain progress, but the pectin extracted still has the problems of impurities and high ash content, which needs further refining treatment to meet the requirements of practical application. SUMMARY

[0007] Based on the above technical problems existing in the prior art, the present application provides a method for extracting low-ash hemp pectin, which can obtain pectin with low ash and impurities and high galacturonic acid content, and can be directly used as a food additive or a pharmaceutical excipient pectin in the fields of food and medicine.

[0008] In order to achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0009] A method for extracting low-ash red hemp / sword hemp / ramie pectin, comprising the following steps:

[0010] S1, raw material pretreatment: washing and enzyme inactivation treatment of red hemp / sword hemp / ramie raw materials;

[0011] S2, deashing treatment: adding the pretreated raw material into ethylenediamine tetraacetic acid solution and / or ethylenediamine tetraacetic acid disodium solution, and then treating by ultrasonic; after ultrasonic treatment, standing, solid-liquid separation, collecting the solid and washing with deionized water to obtain the deashed raw material;

[0012] S3, acid-extracting pectin: adding the deashed raw material obtained in step S2 into nitric acid solution, and extracting by heating; after the extraction is completed, solid-liquid separation is performed, and the first filtrate is collected;

[0013] S4, adding cation exchange resin into the first filtrate for reaction, and after the reaction is completed, solid-liquid separation is performed, and the second filtrate is collected;

[0014] S5, adding an ethanol solution with a mass concentration of ≥95% into the second filtrate for reaction, and after the reaction is completed, solid-liquid separation is performed, and the precipitate is collected;

[0015] S6, washing and drying the precipitate obtained in step S5 to obtain the low-ash pectin finished product.

[0016] In some embodiments, in step S2, the concentration of the ethylenediamine tetraacetic acid solution or ethylenediamine tetraacetic acid disodium solution is 0.5-1.5wt%.

[0017] In some embodiments, in step S2, the solid-liquid ratio of the raw material and the solution is 1g:5-20mL; that is, the solid-liquid ratio of the raw material and the ethylenediaminetetraacetic acid solution is 1g:5-20mL; or the solid-liquid ratio of the raw material and the disodium ethylenediaminetetraacetate solution is 1g:5-20mL; or the solid-liquid ratio of the solution in which the ethylenediaminetetraacetic acid solution and the disodium ethylenediaminetetraacetate solution are mixed is 1g:5-20mL.

[0018] In some embodiments, in step S3, the final concentration of the nitric acid solution is 4-6g / L; and the solid-liquid ratio of the deashed raw material and the nitric acid solution is 1g:4-6mL.

[0019] In some embodiments, in step S3, after mixing the deashed raw material and the nitric acid solution, the temperature is raised to 80-90℃, and the mixture is incubated for 0.5-2h, and the ultrasonic treatment is performed once every 20-40min, with an ultrasonic power of 200-400w and an ultrasonic time of 20-45s.

[0020] In some embodiments, in step S2, the deashing method is as follows:

[0021] The pretreated raw material is added into the ethylenediaminetetraacetic acid solution and / or the disodium ethylenediaminetetraacetate solution at a solid-liquid ratio of 1g:5-20mL, and then ultrasonic treatment is performed at 10-50℃ for 20-40min, with an ultrasonic power of 30-50kHz; after the ultrasonic treatment, the mixture is allowed to stand; and the total deashing treatment time is controlled to be 2-4h.

[0022] In some embodiments, in step S1, the pretreatment method is as follows: after the kenaf / sisal / rice straw raw material is washed with water, the raw material is placed in a container, and then boiled water bath treatment is performed for 2-10min to inactivate the pectinase.

[0023] In some embodiments, in step S4, the cation exchange resin is a strong acid cation exchange resin; and the solid-liquid ratio of the cation exchange resin and the first filtrate is 1g:10-15mL.

[0024] In some embodiments, in step S5, the concentration of the ethanol solution is 95-99%; and the volume of the ethanol solution is 1.5-3 times the volume of the second filtrate.

[0025] In some embodiments, in step S6, the precipitate is washed with anhydrous ethanol, and then dried in a vacuum drying oven at 40-60℃ until the weight is constant, and then crushed to obtain the low-ash pectin product.

[0026] In the above technical solutions, the "kenaf / sisal / rice straw" refers to at least one of kenaf, sisal and rice straw.

[0027] Compared with the prior art, the application has the following beneficial effects:

[0028] The application adopts kenaf / sisal / rumex raw materials, and obtains a low-ash pectin product through pretreatment-deashing treatment-acid extraction of pectin-adsorption of pigment-alcohol precipitation filtration-washing and drying; the application pretreats, extracts and post-treats the kenaf or sisal or rumex raw material through a specific method, so that the pectin yield is higher, the ash content is low, the galacturonic acid content is high, and the pectin can be directly used as a food additive or a pharmaceutical excipient.

[0029] The method of the application extracts pectin from kenaf / sisal / rumex, expands the source of pectin raw materials, and provides a new idea for comprehensive utilization of kenaf, sisal and rumex. DETAILED DESCRIPTION

[0030] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without the specific details set forth in this description. In other instances, well-known methods have not been described in detail in order to avoid obscuring the present application.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application.

[0032] Example 1

[0033] A low-ash kenaf pectin extraction method, comprising the following steps:

[0034] S1, raw material pretreatment: after the kenaf bast raw material is cleaned and dusted with tap water, it is placed in a container, mixed with water, and then treated in a boiling water bath for 5 min to inactivate pectinase;

[0035] S2, deashing treatment: the pretreated raw material is added to an ethylenediaminetetraacetic acid solution with a concentration of 1wt% at a solid-liquid ratio of 1g:10mL, then ultrasonic treatment is performed at 50℃ for 30min, and the ultrasonic power is 40kHz; after ultrasonic treatment, the sample is left to stand for 2h, then solid-liquid separation is performed, and the collected solid is washed with deionized water to obtain the deashed raw material;

[0036] S3, acid extraction of pectin: the deashed raw material obtained in step S2 is mixed with a nitric acid solution, the final concentration of the nitric acid solution is controlled to be 6g / L, the temperature is raised to 85℃ for extraction, and the temperature is kept for 2h; ultrasonic treatment is performed every 20min, the ultrasonic power is 40w, and the ultrasonic time is 30s; after extraction, solid-liquid separation is performed, and the first filtrate is collected;

[0037] S4, adding strong acid cation exchange resin to the first filtrate for adsorption reaction, after the reaction is completed, solid-liquid separation, collecting the second filtrate; the solid-liquid ratio of the first filtrate and the cation exchange resin is 1g:10mL;

[0038] S5, adding 2 times volume of 95wt% ethanol solution to the second filtrate, fully mixing, standing and precipitating, solid-liquid separation, collecting the precipitate;

[0039] S6, washing the precipitate obtained in step S5 with anhydrous ethanol, and then placing it in a vacuum drying box and drying to constant weight at a temperature of 40℃ to obtain a low-ash pectin product.

[0040] Example 2

[0041] A low-ash pectin extraction method, comprising the following steps:

[0042] S1, raw material pretreatment: after the sisal residue raw material is washed to remove impurities with tap water, it is placed in a container, mixed with water, and then treated in a boiling water bath for 5min to inactivate pectinase;

[0043] S2, deashing treatment: the pretreated raw material is added to a 1wt% ethylenediaminetetraacetic acid solution at a solid-liquid ratio of 1g:10mL, and then ultrasonic treatment is performed at 50℃ for 30min at an ultrasonic power of 40kHz; after ultrasonic treatment, stand for 2h, solid-liquid separation, collect the solid and wash it with deionized water to obtain the deashed raw material;

[0044] S3, acid extraction of pectin: the deashed raw material obtained in step S2 is mixed with nitric acid solution, the final concentration of the nitric acid solution is controlled to be 6g / L, the temperature is raised to 85℃ for extraction, and the temperature is kept for 2h, ultrasonic treatment is performed every 20min, ultrasonic power is 40w, 30s; after the extraction is completed, solid-liquid separation, collecting the first filtrate;

[0045] S4, adding strong acid cation exchange resin to the first filtrate for adsorption reaction, after the reaction is completed, solid-liquid separation, collecting the second filtrate; the solid-liquid ratio of the first filtrate and the cation exchange resin is 1g:10mL;

[0046] S5, adding 2 times volume of 95wt% ethanol solution to the second filtrate, fully mixing, standing and precipitating, solid-liquid separation, collecting the precipitate;

[0047] S6, washing the precipitate obtained in step S5 with anhydrous ethanol, and then placing it in a vacuum drying box and drying to constant weight at a temperature of 40℃ to obtain a low-ash pectin product.

[0048] Example 3

[0049] A low-ash pectin extraction method, comprising the following steps:

[0050] S1, raw material pretreatment: after the ramie bast raw material is cleaned with tap water to remove impurities, it is placed in a container, mixed with water, and then treated in a boiling water bath for 5 min to inactivate pectinase;

[0051] S2, deashing treatment: the pretreated raw material is added to a 1wt% ethylenediaminetetraacetic acid solution at a solid-liquid ratio of 1g:10mL, then ultrasonic treatment is performed at 50°C for 30min, the ultrasonic power is 40kHz; after ultrasonic treatment, stand for 2h, solid-liquid separation, collect the solid and wash with deionized water to obtain the deashed raw material;

[0052] S3, acid extraction of pectin: the deashed raw material obtained in step S2 is mixed with nitric acid solution, the final concentration of nitric acid solution is controlled at 6g / L, the temperature is raised to 85°C for extraction, and the temperature is kept for 2h, ultrasonic treatment is performed every 20min, the ultrasonic power is 40w, 30s; after extraction, solid-liquid separation, collect the first filtrate;

[0053] S4, add strong acid cation exchange resin to the first filtrate for adsorption reaction, after the reaction is completed, solid-liquid separation, collect the second filtrate; the solid-liquid ratio of the first filtrate and the cation exchange resin is 1g:10ml;

[0054] S5, add 2 times volume of 95% mass concentration ethanol solution to the second filtrate, mix thoroughly, stand for precipitation, solid-liquid separation, collect the precipitate;

[0055] S6, the precipitate obtained in step S5 is washed with anhydrous ethanol, then placed in a vacuum drying oven, dried at a temperature of 40°C to constant weight, to obtain low-ash pectin product.

[0056] Comparative example 1

[0057] A method for extracting low-ash pectin from red ramie, comprising the following steps:

[0058] S1, raw material pretreatment: after the red ramie bast raw material is cleaned with tap water to remove dust, it is placed in a container, mixed with water, and then treated in a boiling water bath for 5 min to inactivate pectinase;

[0059] S2, deashing treatment: the pretreated raw material is added to a 1wt% ethylenediaminetetraacetic acid solution at a solid-liquid ratio of 1g:10mL, then ultrasonic treatment is performed at 50°C for 30min, the ultrasonic power is 40kHz; after ultrasonic treatment, stand for 2h, solid-liquid separation, collect the solid and wash with deionized water to obtain the deashed raw material;

[0060] S3, acid-extracting pectin: the de-ashed raw material obtained in step S2 is mixed with nitric acid solution, the final concentration of the nitric acid solution is controlled to be 6 g / L, and extraction is performed by heating to 85 DEG C and keeping for 2 h, with ultrasonic treatment once every 20 min, ultrasonic power 40 w, 30 s; after the extraction is completed, solid-liquid separation is performed, and the first filtrate is collected;

[0061] S4, 2 times the volume of 95% mass concentration ethanol solution is added to the first filtrate, mixed thoroughly, and then left to stand for precipitation, followed by solid-liquid separation, and collection of the precipitate;

[0062] S5, the precipitate obtained in step S4 is washed with anhydrous ethanol, and then placed in a vacuum drying oven, dried to constant weight at a temperature of 40 DEG C, to obtain low-ash pectin product.

[0063] Comparative Example 2

[0064] A method for extracting low-ash pectin from red hemp, comprising the following steps:

[0065] S1, raw material pretreatment: after the red hemp bast raw material is washed with tap water to remove dust, it is placed in a container, mixed with water, and then treated in a boiling water bath for 5 min to inactivate pectinase;

[0066] S2, acid-extracting pectin: the pretreated raw material is mixed with 6 g / L nitric acid solution at a bath ratio of 1 g:10 mL, and then 1 wt% ethylenediaminetetraacetic acid (EDTA) is added, and extraction is performed by heating to 85 DEG C and keeping for 2 h, with ultrasonic treatment once every 20 min, ultrasonic power 40 w, 30 s; after the extraction is completed, solid-liquid separation is performed, and the first filtrate is collected;

[0067] S3, strong acid cation exchange resin is added to the first filtrate for adsorption reaction, and after the reaction is completed, solid-liquid separation is performed, and the second filtrate is collected; the solid-liquid ratio of the first filtrate and the cation exchange resin is 1 g:10 ml;

[0068] S4, 2 times the volume of 95% mass concentration ethanol solution is added to the second filtrate, mixed thoroughly, and then left to stand for precipitation, followed by solid-liquid separation, and collection of the precipitate;

[0069] S5, the precipitate obtained in step S4 is washed with anhydrous ethanol, and then placed in a vacuum drying oven, dried to constant weight at a temperature of 40 DEG C, to obtain low-ash pectin product.

[0070] Comparative Example 3

[0071] A method for extracting low-ash pectin from red hemp, comprising the following steps:

[0072] S1, raw material pretreatment: after the red hemp bast raw material is washed with tap water to remove dust, it is placed in a container, mixed with water, and then treated in a boiling water bath for 5 min to inactivate pectinase;

[0073] S2, deashing treatment: the pretreated raw material was added to deionized water at a solid-liquid ratio of 1 g: 10 mL, then ultrasonic treatment was carried out at 50°C for 30 min, the ultrasonic power was 40 kHz; after ultrasonic treatment, it was placed for 2 h, solid-liquid separation was carried out, the collected solid was washed with deionized water, and the deashed raw material was obtained;

[0074] S3, acid-extracting pectin: the deashed raw material obtained in step S2 was added to nitric acid solution, the final concentration of the nitric acid solution was controlled to be 6 g / L, and extraction was carried out by heating to 85°C, and the temperature was kept for 2 h, ultrasonic treatment was carried out every 20 min, the ultrasonic power was 40 w, and the ultrasonic time was 30 s; after extraction, solid-liquid separation was carried out, and the first filtrate was collected;

[0075] S4, strong acid cation exchange resin was added to the first filtrate for adsorption reaction, after the reaction was completed, solid-liquid separation was carried out, and the second filtrate was collected; the solid-liquid ratio of the first filtrate and the cation exchange resin was 1 g: 10 mL;

[0076] S5, 2 times the volume of 95% mass concentration ethanol solution was added to the second filtrate, mixed thoroughly, and then precipitated, solid-liquid separation was carried out, and the precipitate was collected;

[0077] S6, the precipitate obtained in step S5 was washed with anhydrous ethanol, and then placed in a vacuum drying oven, dried at a temperature of 40°C until the weight was constant, and the low-ash pectin product was obtained.

[0078] Comparative Example 4

[0079] A method for extracting low-ash red pectin, comprising the following steps:

[0080] S1, raw material pretreatment: after the red pectin raw material was washed with tap water to remove dust, it was placed in a container, mixed with water, and then treated in a boiling water bath for 5 min to inactivate pectinase;

[0081] S2, deashing treatment: the pretreated raw material was added to a 1wt% ethylenediaminetetraacetic acid solution at a solid-liquid ratio of 1 g: 10 mL, then ultrasonic treatment was carried out at 50°C for 30 min, the ultrasonic power was 40 kHz; after ultrasonic treatment, it was placed for 2 h, solid-liquid separation was carried out, the collected solid was washed with deionized water, and the deashed raw material was obtained;

[0082] S3, acid-extracting pectin: the deashed raw material obtained in step S2 was added to sulfuric acid solution, the final concentration of the sulfuric acid solution was controlled to be 6 g / L, and extraction was carried out by heating to 85°C, and the temperature was kept for 2 h, ultrasonic treatment was carried out every 20 min, the ultrasonic power was 40 w, and the ultrasonic time was 30 s; after extraction, solid-liquid separation was carried out, and the first filtrate was collected;

[0083] S4, adding strong acidic cation exchange resin to the first filtrate for adsorption reaction, after the reaction, solid-liquid separation, collecting the second filtrate; the solid-liquid ratio of the first filtrate and cation exchange resin is 1g:10mL;

[0084] S5, adding 2 times volume of 95% mass concentration ethanol solution to the second filtrate, mixing well, standing and precipitating, solid-liquid separation, collecting the precipitate;

[0085] S6, washing the precipitate obtained in step S5 with anhydrous ethanol, then placing in a vacuum drying oven, drying at a temperature of 40℃ to constant weight, obtaining low-ash pectin product.

[0086] It is detected that the quality and yield of pectin obtained by the method of examples 1-3 and comparative examples 1-4 are shown in the following table 1:

[0087] Table 1 quality and yield of pectin of examples 1-3 and comparative examples 1-4

[0088] Pectin yield (%) Galacturonic acid content (%) Ash content (%) Example 1 2.080 84.9 4.43 Example 2 2.164 82.5 3.61 Example 3 1.890 78.7 4.34 Comparative Example 1 1.760 58.6 16.06 Comparative Example 2 1.420 66.0 8.36 Comparative Example 3 1.048 65.9 9.39 Comparative Example 4 2.637 52.4 15.49

[0089] The technical features of the above-described embodiments can be combined arbitrarily, and in order to make the description simple, all possible combinations of the technical features in the above-described embodiments are not described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0090] The above-described embodiments only express several embodiments of the present application, the description is more specific and detailed, but it should not be understood as the limitation of the scope of the application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of variations and improvements can be made, which belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method for extracting low ash pectin from red / sisal / ramie fibers, characterized by, The method comprises the following steps: S1, raw material pretreatment: washing and enzyme inactivation treatment of Kenaf / Sisal / Ramie raw material; S2, deashing treatment: adding the pretreated raw material into ethylenediaminetetraacetic acid solution or disodium ethylenediaminetetraacetate solution, and then performing ultrasonic treatment; after ultrasonic treatment, standing, solid-liquid separation, washing the collected solid with deionized water, and obtaining the deashed raw material; S3, acid extraction of pectin: adding the deashed raw material obtained in step S2 into nitric acid solution, and heating to 80-90℃ for extraction; after completion of the extraction, performing solid-liquid separation, and collecting the first filtrate; S4, adding cation exchange resin into the first filtrate for reaction, and after completion of the reaction, performing solid-liquid separation, and collecting the second filtrate; S5, adding ethanol solution with mass concentration ≥95% into the second filtrate for reaction, and after completion of the reaction, performing solid-liquid separation, and collecting the precipitate; S6, washing and drying the precipitate obtained in step S5 to obtain low-ash pectin product; In step S2, the concentration of the ethylenediaminetetraacetic acid solution or disodium ethylenediaminetetraacetate solution is 0.5-1.5wt%; and the solid-liquid ratio of the raw material and the solution is 1g:5-20mL; In step S3, the solid-liquid ratio of the deashed raw material and the nitric acid solution is 1g:4-6mL, and the final concentration of the nitric acid solution is 4-6g / L.

2. The process for the extraction of low ash red / sisal / ramie pectin according to claim 1, characterized in that, In step S3, after mixing the deashed raw material and the nitric acid solution, heat preservation is performed for 0.5-2h, ultrasonic treatment is performed once every 20-40min, the ultrasonic power is 200-400w, and the ultrasonic time is 20-45s.

3. The process for the extraction of low ash pectin from Enseada / Manila / Ramie as claimed in claim 1, wherein, In step S2, the deashing treatment method is specifically as follows: After the pretreated raw material is added into the ethylenediaminetetraacetic acid solution or disodium ethylenediaminetetraacetate solution with a concentration of 0.5-1.5wt% at a solid-liquid ratio of 1g:5-20mL, ultrasonic treatment is performed at 10-50℃ for 20-40min, and the ultrasonic frequency is 30-50kHz; after completion of the ultrasonic treatment, standing is performed; and the total deashing treatment time is controlled to be 2-4h.

4. The process for the extraction of low ash red / sisal / ramie pectin according to claim 1, characterized in that, In step S1, the pretreatment method is as follows: after the Kenaf / Sisal / Ramie raw material is washed with water, the raw material is placed in a container, and then boiled water bath treatment is performed for 2-10min to inactivate pectinase.

5. The process for the extraction of low ash red / sisal / ramie pectin according to claim 1, characterized in that, In step S4, the cation exchange resin is a strong acid cation exchange resin; and the solid-liquid ratio of the cation exchange resin and the first filtrate is 1g:10-15ml.

6. The process for the extraction of low ash red / sisal / ramie pectin according to claim 1, characterized in that, In step S5, the concentration of the ethanol solution is 95-99%; and the volume of the ethanol solution is 1.5-3 times the volume of the second filtrate.

7. The process for the extraction of low ash red jute / sisal / ramie pectin as claimed in claim 1, wherein, In step S6, the precipitate is washed with anhydrous ethanol, and then placed in a vacuum drying oven for drying at 40-60℃ until the weight is constant, and then pulverized to obtain the low-ash pectin product.