CN106243242A - A kind of utilize degraded the solubilization technique method that Fructus Jujubae pectin is prepared in extraction from Fructus Jujubae Fructus Jujubae slag - Google Patents

Abstract

The present invention is a kind of utilizes the degraded solubilization technique method that Fructus Jujubae pectin is prepared in extraction from Fructus Jujubae Fructus Jujubae slag, belongs to technical field of food biotechnology；Comprising the following steps, Fructus Jujubae slag pretreatment, demetalization ion, the multienzyme method of fractional steps is extracted, and first carries out cellulase, hemicellulose complex enzyme zymohydrolysis, then carries out protease, lipase complex enzyme zymohydrolysis, centrifugal, and decolouring concentrates, and is dried, prepares finished product；The present invention uses many enzyme extraction methods to combine chelating method and extracts Fructus Jujubae pectin；Obtain the specific Fructus Jujubae pectin product with enhancing human body immunity that a kind of purity is high, gelation is good, make full use of Fructus Jujubae and be worth, improve Fructus Jujubae resource utilization, reduce environmental pollution and the wasting of resources simultaneously；Through technology purification pectin products such as decolouring and membrance separation, product purity is high, and extraction ratio is high.

Description

A method for preparing jujube pectin from jujube dregs by using degradation and solubilization technology method

technical field

The invention discloses a method for extracting and preparing jujube pectin from jujube dregs by using degradation and solubilization technology, belonging to the field of food biotechnology.

Background technique

Pectin is one of the components of the cell wall of tissues. It exists in the cell layer between adjacent cell walls and plays the role of sticking the cell walls together. Different sources of pectin have different properties. Natural pectin is mainly linear polysaccharides, containing a chain structure of several hundred to more than 1,000 glycogens, with an average molecular weight of 500,000-1.5 million. The basic component of the main chain molecule of pectin is D-galacturonic acid, and some natural neutral sugars such as rhamnose, arabinose, xylose, galactose, glucose, etc. also exist in pectin. Pectin is a yellowish white powder that dissolves in water to form a viscous, odorless solution that is negatively charged. Pectin is a natural polymer compound with good gelation and emulsification stability, and has been widely used in food, medicine, daily chemical and textile industries.

According to reports, the annual demand for pectin in the world is nearly 45,000 tons. At present, my country consumes more than 1,500 tons of pectin every year, of which 80% are imported from abroad. As a food additive, the demand for pectin will continue to grow at an annual rate of 15% for quite a long time. Because the price of imported pectin is 1 to 2 times the price of domestic pectin, there is an urgent need for low-priced, high-quality domestic pectin in production. Increasing pectin production and improving pectin quality are the goals of the development of my country's pectin industry. Make full use of my country's rich pectin resources to produce high-quality pectin to meet the needs of the domestic market and in line with the development direction of my country's food additive industry.

Jujube is a special fruit in China with a long history of cultivation. Jujube is rich in nutrition and comprehensive, and it is a fruit with high nutritional and medicinal value. Jujube dregs are the by-products of jujube processing. However, due to the low content of functional substances in jujube dregs and jujube skin, the extraction rate is low, the extraction process is complicated, and the organic solvents used are easy to pollute the environment. At the same time, most other pectin polysaccharides cannot Fully utilized, so it cannot be widely used in industrial production. In addition, due to weak technology, the development and utilization of jujube dregs and jujube skin, a by-product of jujube processing, is still in its infancy. It is mainly used as livestock feed or discharged as waste, causing environmental pollution and waste of resources.

The content of pectin resources in jujube is very rich, especially in jujube skin and jujube dregs. The molecular weight of jujube pectin is above 2000kD (the pectin products with high gel degree and stable quality are all concentrated in the range of large molecular weight), which is far greater than the molecular weight of pectin extracted from other plants. At the same time, studies have shown that jujube pectin has a certain enhancement The role of the body's immunity. Therefore, jujube jujube dregs are selected as raw materials for pectin extraction, and pectin substances with good gel effect and specificity for enhancing the body's immunity can be obtained.

However, pectin in jujube is difficult to decolorize and purify. The red pigment in jujube is darker and contains relatively more calcium and iron ions, and calcium and iron ions have a strong sealing effect on pectin, which is not conducive to the dissolution of pectin (deblocking ions). Jujube pectin A large amount of calcium ions are chelated in the cell, and at the same time, it forms a fibrous space structure with cellulose, protein, lipid and starch in the form of covalent or non-covalent bonds, making it difficult to dissolve pectin. At the same time, jujube pectin also contains a large amount of fat-soluble components, which have a great impact on the purification of pectin (skimmed matter). However, the common acid-base extraction method cannot completely extract the pectin substance in jujube, and it will also destroy the molecular structure of the pectin substance.

Contents of the invention

The present invention overcomes the deficiencies of the prior art, and the technical problem to be solved is to provide a method for extracting and preparing jujube pectin from jujube dregs by using degradation and solubilization technology, so as to obtain a kind of pectin with high purity and good gelling property and enhanced body Immune specific jujube pectin products; use jujube dregs to extract pectin products, make full use of the value of jujube, and improve the utilization rate of jujube resources.

In order to solve the above-mentioned technical problems, the technical solution adopted in the present invention is: a method for extracting and preparing jujube pectin from jujube dregs by using degradation and solubilization technology, comprising the following steps:

The first step is pretreatment and sterilization of jujube dregs; crush jujube dregs, pass through a 100-mesh sieve, add 95% ethanol by volume to reflux for 20 minutes, filter to remove ethanol, rinse jujube dregs with distilled water until the washing liquid is colorless, and bake at 60°C dry and ready for use;

In addition to rich pectin, jujube dregs also contain pectinases that can decompose pectin, including pectinesterase and pectin lyase. In the process, the neutral sugar side chains on the pectin molecules will be degraded and eliminated in large quantities, making the molecular weight of pectin smaller and the spatial structure changed, which will lead to a decrease in extraction rate and quality. Therefore, jujube dregs are generally pretreated before pectin is extracted to achieve the purpose of inactivating pectinase.

The second step is to remove metal ions; using EDTA chelating agent-assisted method, add the jujube dregs sample obtained in the previous step into 0.05mol/L EDTA solution, so that the liquid-solid ratio is 24:1 (L/kg), extract The temperature is 35°C, the time is 3-4h, and the extract is obtained;

Jujube cells contain relatively many calcium and iron ions, and calcium and iron ions have a strong sealing effect on pectin, and the presence of calcium and iron ions is not conducive to the dissolution of pectin (deblocking ions). At the same time, the existence of metal ions will Inhibits the action of enzymes. Therefore, before enzymatic extraction of pectin, a chelating agent is used to remove Ga ions from the pectin structure.

The third step is multi-enzyme step-by-step extraction; firstly carry out enzymatic hydrolysis with cellulase and hemicellulose compound enzyme, then carry out the enzymatic hydrolysis of the above extract with cellulase and hemicellulose compound enzyme, and obtain the best The enzymatic hydrolysis conditions are: compound enzyme mixed with cellulase: hemicellulase 1.2:1, temperature 45°C, pH 4.5, enzyme dosage 0.8%, extraction time 4-5h;

Then carry out protease and lipase compound enzyme enzymatic hydrolysis. After the above enzymatic hydrolysis reaction is completed, adjust the temperature of the reaction solution to 55 ° C and pH 6, and add papain and lipase to the reaction solution in a ratio of 1:1. 1.0%, the extraction time is 3-4h. Obtain pectin enzymatic hydrolysis solution;

At present, the extraction methods of pectin mainly include acid extraction, enzyme extraction, microbial fermentation and so on. The principle of the acid extraction method is to use dilute acid to hydrolyze the non-water-soluble protopectin in the pericarp cells into water-soluble pectin, and the yield of pectin can reach more than 26%, but the pectin molecules will be partially hydrolyzed during the extraction process, reducing the yield of pectin. The relative molecular weight of pectin is affected, thereby affecting the yield and quality of pectin. For example, the extraction process generally adopts higher temperature and long-term heating, so that the pectin in the raw material is inevitably deformed, decomposed and damaged, and the quality is poor. In addition, due to the high viscosity of the extract and slow filtration, the production cycle is long and the efficiency is low; the enzyme extraction method is an extraction method that has developed rapidly in the field of natural extraction in recent years. It has the advantages of high quality and energy saving, but because different raw materials have different requirements for enzymes, it increases the technical difficulty. In addition, the extraction by a single enzyme system cannot completely extract the pectin substance, resulting in a low extraction rate. Therefore, a multi-enzyme step-by-step extraction method is adopted, and different enzyme systems are used step by step according to the structure of the pectin, so that the jujube pectin is completely separated from its fiber network structure.

(1) Cellulase, hemicellulase: most pectin substances are associated with macromolecules such as cellulose and hemicellulose in the cell wall in the form of covalent or non-covalent bonds, and they are more The polymers associate with each other through secondary bonds to form a fibrous spatial structure.

(2) Protease and lipase: Red dates are rich in protein and fat substances, which are combined in the pectin structure in the form of covalent bonds or non-covalent bonds, resulting in a decrease in the water solubility of pectin.

The fourth step is centrifugation; the pectin enzymatic hydrolysis solution obtained in the third step is centrifuged at 15,000 r/min for 5 minutes to remove insoluble matter and enzyme agent to obtain a pectin extract.

Remove insoluble matter and enzymes, but after enzymatic hydrolysis and extraction, small molecular impurities such as pigments will be incorporated into the enzymatic hydrolysis solution, and pectin products need to be purified by decolorization and membrane separation.

The fifth step is decolorization; the processed D900 type decolorization resin is loaded into a chromatographic column with a specification of 600mm × 50mm, and the loading amount is 2/3 of the height of the column, and the pH value is adjusted to 6 for subsequent use, and the fourth step is obtained The pectin extract solution is decolorized by resin at a flow rate of 200mL/h at room temperature, and the decolorized pectin extract solution is collected for subsequent use;

The red pigment in jujube is deep and difficult to decolorize. In the first step, ethanol treatment can remove part of the pigment on the surface, but most of the pigment molecules still exist in the jujube dregs. With the extraction of pectin, they dissolve into the enzyme solution, affecting the purity of pectin. Therefore, it is necessary to choose a suitable decolorization method for decolorization.

The macroporous adsorption resin method is used for decolorization. This method has large processing capacity, high decolorization capacity, can remove various pigments, can be recycled repeatedly, has a long service life, low cost, and reduces the pollution of chemical substances to pectin.

The sixth step is concentration; 5 kinds of ultrafiltration membrane modules with different molecular weight cut-offs (300KD, 100KD, 30KD, 10KD, 5KD) are used to separate pectin. The liquid is sequentially input into the membrane modules with molecular weight from large to small through the circulation pump, and after ultrafiltration separation, six parts of pectin sample liquids greater than 300KD, 300KD-100KD, 100KD-30KD, 30KD-10KD, 10KD-5KD and less than 5KD are obtained. ;

Using membrane separation and concentration method. The vacuum concentration method is easy to cause browning of the pectin solution, which affects the quality. Therefore, the membrane separation and concentration method is adopted. This method can selectively separate sugars and other low-molecular compounds from the pectin extract, thereby obtaining high-quality pectin , this technology is simple and efficient, low-carbon and environmentally friendly, which is conducive to the maintenance of equipment and the maintenance of the excellent quality of pectin. At the same time, pectin products with different molecular weight ranges can be obtained according to different molecular weights of the membranes. Pectin products with different molecular weights have different effects , while pectin products with high gel degree and stable quality are all concentrated in the range of large molecular weight.

The seventh step is drying; use a spray dryer to dry, spray and dry pectin sample liquids of different components at 130°C to 160°C instantaneously to obtain pectin products with different molecular weights; the dried products are sieved through a 60-mesh sieve, That is, different molecular weight pectin powders are obtained;

The drying technology of pectin has an important influence on the quality of pectin. There are three main drying methods: low temperature drying, spray drying and vacuum freeze drying. Among them, the pectin product obtained by low-temperature drying has poor solubility and darker color, and vacuum freeze-drying has the disadvantages of large energy consumption and long time. Therefore, the spray-drying method is selected, and the product can be obtained by spray-drying technology without precipitation, and the obtained product has small particles, good solubility and low cost.

The eighth step is to prepare the finished product; select the pectin separated by the ultrafiltration membrane module above 100KD to obtain the finished product of jujube pectin with a molecular weight greater than 100KD.

Since the high molecular weight pectin substance has better gelatinity and stability, the ultrafiltration membrane module with a molecular weight greater than 100KD is selected to separate pectin, and the jujube pectin substance with a molecular weight greater than 100KD is obtained.

The method for preparing jujube pectin from jujube dregs by using degradation and solubilization technology, the finished product of jujube pectin obtained in the eighth step is light yellow or light brown powder, and the drying loss is 5.43 w%±0.12, Sulfur dioxide: 32.21 mg/kg±0.24, acid-insoluble ash: 0.73 w%±0.03, total galacturonic acid: 89.96 w%±0.64, lead: 0.35 mg/kg±0.02. .

In the method for preparing jujube pectin from jujube dregs by using degradation and solubilization technology, in the sixth step, the concentrated jujube pectin is mainly concentrated in the large molecular weight part, reaching more than 90%; wherein the molecular weight is greater than 300KD and reaches 78.24% Above, the 300KD-100KD part accounts for more than 14.31%.

Compared with the prior art, the present invention has the following beneficial effects.

1. The unique nutritional value of jujube pectin. The pectin resource content in jujube is very rich, especially in jujube skin and jujube dregs. The molecular weight of jujube pectin is above 2000kD (the pectin products with high gel degree and stable quality are all concentrated in the range of large molecular weight), which is far greater than the molecular weight of pectin extracted from other plants. At the same time, studies have shown that jujube pectin has a certain enhancement The role of the body's immunity.

2. The present invention adopts a multi-enzyme extraction method combined with a chelation method to extract jujube pectin; a jujube pectin product with high purity and good gelatinity and the specificity of enhancing body immunity is obtained.

3. Using jujube dregs to extract pectin products can make full use of the value of jujube and improve the utilization rate of jujube resources. At the same time reduce environmental pollution and waste of resources.

4. Using multi-enzyme step-by-step extraction method, different enzyme systems are used step by step according to the structure of pectin, so that jujube pectin can be completely separated from its fiber network structure. Carry out cellulase and hemicellulose compound enzyme enzymolysis first to destroy the spatial structure of the substance, which is more conducive to the next step to destroy the covalent bond or non-covalent bond structure; then carry out protease and lipase compound enzyme enzymolysis to make pectin Completely break away from the spatial structure.

5. The pectin product is purified by decolorization and membrane separation technology, so the product has high purity and high extraction rate.

6. Since jujube pectin is mainly concentrated in the large molecular weight part, reaching more than 90%, the molecular weight greater than 300KD accounts for the majority, reaching 78.24%, followed by the 300KD-100KD part, accounting for 14.31%. Therefore, the jujube pectin substance with a molecular weight greater than 100KD is obtained by membrane separation technology.

7. The extraction process is low temperature and pollution-free. Except for the instantaneous high temperature of spray drying during the whole extraction process, the temperature does not exceed 60°C, which avoids the influence of high temperature on the quality of pectin. In addition, no chemical substances are added in the whole process, which avoids the pollution of pectin by chemical substances.

detailed description

The present invention will be further described below in conjunction with specific examples.

Example 1

A method for extracting and preparing jujube pectin from jujube dregs by using degradation solubilization technology, comprising the following steps:

The first step is pretreatment and sterilization of jujube dregs; crush jujube dregs, pass through a 100-mesh sieve, add 95% ethanol by volume to reflux for 20 minutes, filter to remove ethanol, rinse jujube dregs with distilled water until the washing liquid is colorless, and bake at 60°C Obtain the jujube dregs sample after drying for subsequent use;

The second step is to remove metal ions; using EDTA chelating agent-assisted method, add the jujube dregs sample obtained in the previous step into 0.05mol/L EDTA solution, so that the liquid-solid ratio is 24:1 (L/kg), extract The temperature is 35°C, and the time is 3h to obtain the extract;

The third step is multi-enzyme step-by-step extraction; firstly, carry out enzymatic hydrolysis with cellulase and hemicellulose compound enzyme, and then carry out the enzymatic hydrolysis of the above extract with cellulase and hemicellulose compound enzyme. The enzymatic hydrolysis conditions are: use cellulose Enzyme: compound enzyme mixed with hemicellulase 1.2:1, temperature 45°C, pH 4.5, the amount of enzyme added is 0.8% of the mass of the extract, and the extraction time is 4 hours to obtain a reaction solution;

Then carry out protease and lipase compound enzymatic hydrolysis, adjust the temperature of the reaction solution to 55°C, pH6, add papain and lipase to the reaction solution in a ratio of 1:1, the total amount of enzyme is 1.0% of the mass of the reaction solution %, the extraction time is 4h, and the pectin enzymatic hydrolyzate is obtained;

The fourth step is centrifugation; the pectin enzymatic hydrolysis solution obtained in the third step is centrifuged at 15,000 r/min for 5 minutes to remove insoluble matter and enzymes to obtain a pectin extract;

The fifth step is decolorization; the processed D900 type decolorization resin is loaded into a chromatographic column with a specification of 600mm × 50mm, and the loading amount is 2/3 of the height of the column, and the pH value is adjusted to 6 for subsequent use, and the fourth step is obtained The pectin extract solution is decolorized by resin at a flow rate of 200mL/h at room temperature, and the decolorized pectin extract solution is collected for subsequent use;

The sixth step is concentration; 5 kinds of ultrafiltration membrane modules with different molecular weight cut-offs (300KD, 100KD, 30KD, 10KD, 5KD) are used to separate pectin, and at room temperature, the inlet pressure is 70kPa, and the outlet pressure is 30kPa. The liquid is sequentially input into the membrane modules with molecular weight from large to small through the circulation pump, and after ultrafiltration separation, six parts of pectin sample liquids greater than 300KD, 300KD-100KD, 100KD-30KD, 30KD-10KD, 10KD-5KD and less than 5KD are obtained. ;

The seventh step is drying; use a spray dryer to dry, spray and dry pectin sample liquids of different components at 130°C to 160°C instantaneously to obtain pectin products with different molecular weights; the dried products are sieved through a 60-mesh sieve, That is, different molecular weight pectin powders are obtained;

The eighth step is to prepare the finished product; select the pectin separated by the ultrafiltration membrane module above 100KD to obtain the finished product of jujube pectin with a molecular weight greater than 100KD.

The obtained jujube pectin product is light yellow or light brown powder, drying loss is 5.43 w%±0.12, sulfur dioxide: 32.21 mg/kg±0.24, acid-insoluble ash: 0.73 w%±0.03, total galacturonic acid: 89.96 w%±0.64, lead: 0.35 mg/kg±0.02. .

Example 2

A method for extracting and preparing jujube pectin from jujube dregs by using degradation solubilization technology, comprising the following steps:

The first step, jujube dregs pretreatment, sterilization; crush jujube dregs, pass through a 100-mesh sieve, add a certain volume of 95% ethanol to reflux for 20 minutes, filter to remove ethanol, wash jujube dregs with distilled water until the washing liquid is colorless, 60 ° C dry and ready for use;

The second step is to remove metal ions; using EDTA chelating agent-assisted method, add the jujube dregs sample obtained in the previous step into 0.05mol/L EDTA solution, so that the liquid-solid ratio is 24:1 (L/kg), extract The temperature is 35°C, and the time is 4h to obtain the extract;

The third step is multi-enzyme step-by-step extraction; firstly, carry out enzymatic hydrolysis with cellulase and hemicellulose compound enzyme, and then carry out the enzymatic hydrolysis of the above extract with cellulase and hemicellulose compound enzyme. The enzymatic hydrolysis conditions are: use cellulose Enzyme: Hemicellulase 1.2:1 mixed enzyme, temperature 45°C, pH 4.5, enzyme dosage 0.8%, extraction time 5h;

Then carry out protease and lipase compound enzyme enzymolysis, adjust the temperature of the reaction solution to 55 ° C, pH 6, add papain and lipase to the reaction solution in a ratio of 1:1, the enzyme addition is 1.0%, and the extraction time is 3h, obtain pectin enzymatic hydrolysis solution;

The fourth step is centrifugation; the pectin enzymatic hydrolysis solution obtained in the third step is centrifuged at 15,000 r/min for 5 minutes to remove insoluble matter and enzymes to obtain a pectin extract;

The fifth step is decolorization; the processed D900 type decolorization resin is loaded into a chromatographic column with a specification of 600mm × 50mm, and the loading amount is 2/3 of the height of the column, and the pH value is adjusted to 6 for subsequent use, and the fourth step is obtained The pectin extract solution is decolorized by resin at a flow rate of 200mL/h at room temperature, and the decolorized pectin extract solution is collected for subsequent use;

The sixth step is concentration; 5 kinds of ultrafiltration membrane modules with different molecular weight cut-offs (300KD, 100KD, 30KD, 10KD, 5KD) are used to separate pectin. The liquid is sequentially input into the membrane modules with molecular weight from large to small through the circulation pump, and after ultrafiltration separation, six parts of pectin sample liquids greater than 300KD, 300KD-100KD, 100KD-30KD, 30KD-10KD, 10KD-5KD and less than 5KD are obtained. ;

The seventh step is drying; use a spray dryer to dry, spray and dry pectin sample liquids of different components at 130°C to 160°C instantaneously to obtain pectin products with different molecular weights; the dried products are sieved through a 60-mesh sieve, That is, different molecular weight pectin powders are obtained;

The eighth step is to prepare the finished product; select the pectin separated by the ultrafiltration membrane module above 100KD to obtain the finished product of jujube pectin with a molecular weight greater than 100KD.

The obtained jujube pectin product is light yellow or light brown powder, the drying loss is 5.43 w% ± 0.12, sulfur dioxide: 32.21 mg/kg ± 0.24, acid insoluble ash: 0.73 w% ± 0.03, total galactose Alkyd acid: 89.96w%±0.64, lead: 0.35 mg/kg±0.02. .

Example 3

A method for extracting and preparing jujube pectin from jujube dregs by using degradation solubilization technology, comprising the following steps:

The first step, jujube dregs pretreatment, sterilization; crush jujube dregs, pass through a 100-mesh sieve, add a certain volume of 95% ethanol to reflux for 20 minutes, filter to remove ethanol, wash jujube dregs with distilled water until the washing liquid is colorless, 60 ° C dry and ready for use;

The second step is to remove metal ions; using EDTA chelating agent-assisted method, add the jujube dregs sample obtained in the previous step into 0.05mol/L EDTA solution, so that the liquid-solid ratio is 24:1 (L/kg), extract The temperature is 35°C, and the time is 3.5h to obtain the extract;

The third step is multi-enzyme step-by-step extraction; firstly, carry out enzymatic hydrolysis with cellulase and hemicellulose compound enzyme, and then carry out the enzymatic hydrolysis of the above extract with cellulase and hemicellulose compound enzyme. The enzymatic hydrolysis conditions are: use cellulose Enzyme: compound enzyme mixed with hemicellulase 1.2:1, temperature 45°C, pH 4.5, enzyme dosage 0.8%, extraction time 4.5h;

Then carry out protease and lipase compound enzyme enzymolysis, adjust the temperature of the reaction solution to 55 ° C, pH 6, add papain and lipase to the reaction solution in a ratio of 1:1, the enzyme addition is 1.0%, and the extraction time is 3.5h, obtain pectin enzymatic hydrolysis solution;

The fourth step is centrifugation; the pectin enzymatic hydrolysis solution obtained in the third step is centrifuged at 15,000 r/min for 5 minutes to remove insoluble matter and enzymes to obtain a pectin extract;

The fifth step is decolorization; the processed D900 type decolorization resin is loaded into a chromatographic column with a specification of 600mm × 50mm, and the loading amount is 2/3 of the height of the column, and the pH value is adjusted to 6 for subsequent use, and the fourth step is obtained The pectin extract solution is decolorized by resin at a flow rate of 200mL/h at room temperature, and the decolorized pectin extract solution is collected for subsequent use;

The sixth step is concentration; 5 kinds of ultrafiltration membrane modules with different molecular weight cut-offs (300KD, 100KD, 30KD, 10KD, 5KD) are used to separate pectin. The liquid is sequentially input into the membrane modules with molecular weight from large to small through the circulation pump, and after ultrafiltration separation, six parts of pectin sample liquids greater than 300KD, 300KD-100KD, 100KD-30KD, 30KD-10KD, 10KD-5KD and less than 5KD are obtained. ;

The seventh step is drying; use a spray dryer to dry, spray and dry pectin sample liquids of different components at 130°C to 160°C instantaneously to obtain pectin products with different molecular weights; the dried products are sieved through a 60-mesh sieve, That is, different molecular weight pectin powders are obtained;

The eighth step is to prepare the finished product; select the pectin separated by the ultrafiltration membrane module above 100KD to obtain the finished product of jujube pectin with a molecular weight greater than 100KD.

The obtained jujube pectin product is light yellow or light brown powder, the drying loss is 5.43 w% ± 0.12, sulfur dioxide: 32.21 mg/kg ± 0.24, acid insoluble ash: 0.73 w% ± 0.03, total galactose Alkyd acid: 89.96w%±0.64, lead: 0.35 mg/kg±0.02. .

Example 4

A method for extracting and preparing jujube pectin from jujube dregs by using degradation solubilization technology, comprising the following steps:

The first step, jujube dregs pretreatment, sterilization; crush jujube dregs, pass through a 100-mesh sieve, add a certain volume of 95% ethanol to reflux for 20 minutes, filter to remove ethanol, wash jujube dregs with distilled water until the washing liquid is colorless, 60 ° C dry and ready for use;

The second step is to remove metal ions; using EDTA chelating agent-assisted method, add the jujube dregs sample obtained in the previous step into 0.05mol/L EDTA solution, so that the liquid-solid ratio is 24:1 (L/kg), extract The temperature is 35°C, and the time is 3h to obtain the extract;

The third step is multi-enzyme step-by-step extraction; firstly, carry out enzymatic hydrolysis with cellulase and hemicellulose compound enzyme, and then carry out the enzymatic hydrolysis of the above extract with cellulase and hemicellulose compound enzyme. The enzymatic hydrolysis conditions are: use cellulose Enzyme: Hemicellulase 1.2:1 mixed enzyme, temperature 45°C, pH 4.5, enzyme dosage 0.8%, extraction time 5h;

Then carry out protease and lipase compound enzyme enzymolysis, adjust the temperature of the reaction solution to 55 ° C, pH 6, add papain and lipase to the reaction solution in a ratio of 1:1, the enzyme addition is 1.0%, and the extraction time is 3h, obtain pectin enzymatic hydrolysis solution;

The fourth step is centrifugation; the pectin enzymatic hydrolysis solution obtained in the third step is centrifuged at 15,000 r/min for 5 minutes to remove insoluble matter and enzymes to obtain a pectin extract;

The fifth step is decolorization; the processed D900 type decolorization resin is loaded into a chromatographic column with a specification of 600mm × 50mm, and the loading amount is 2/3 of the height of the column, and the pH value is adjusted to 6 for subsequent use, and the fourth step is obtained The pectin extract solution is decolorized by resin at a flow rate of 200mL/h at room temperature, and the decolorized pectin extract solution is collected for subsequent use;

The sixth step is concentration; 5 kinds of ultrafiltration membrane modules with different molecular weight cut-offs (300KD, 100KD, 30KD, 10KD, 5KD) are used to separate pectin. The liquid is sequentially input into the membrane modules with molecular weight from large to small through the circulation pump, and after ultrafiltration separation, six parts of pectin sample liquids greater than 300KD, 300KD-100KD, 100KD-30KD, 30KD-10KD, 10KD-5KD and less than 5KD are obtained. ;

The seventh step is drying; use a spray dryer to dry, spray and dry pectin sample liquids of different components at 130°C to 160°C instantaneously to obtain pectin products with different molecular weights; the dried products are sieved through a 60-mesh sieve, That is, different molecular weight pectin powders are obtained;

The eighth step is to prepare the finished product; select the pectin separated by the ultrafiltration membrane module above 100KD to obtain the finished product of jujube pectin with a molecular weight greater than 100KD.

The obtained jujube pectin product is light yellow or light brown powder, drying loss is 5.43 w%±0.12, sulfur dioxide: 32.21 mg/kg±0.24, acid-insoluble ash: 0.73 w%±0.03, total galacturonic acid: 89.96 w%±0.64, lead: 0.35 mg/kg±0.02. .

The present invention may be embodied in other specific forms without departing from the spirit or main characteristics of the invention. Therefore, no matter from which point of view, the above-mentioned embodiments of the present invention can only be considered as explanations of the present invention and can not limit the invention. The claims indicate the scope of the present invention, but the above description does not indicate the scope of the present invention. Therefore, any changes within the meaning and scope equivalent to the claims of the present invention should be considered to be included in the scope of the claims.

Claims (5)

1. a method utilizing degradation solubilization technology to extract and prepare jujube pectin from jujube dregs, is characterized in that, comprises the following steps: The first step is pretreatment and sterilization of jujube dregs; crush jujube dregs, pass through a 100-mesh sieve, add 95% ethanol to reflux for 20 minutes, filter to remove ethanol, rinse jujube dregs with distilled water until the washing liquid is colorless, and dry at 60°C Obtain the jujube dregs sample for subsequent use; The second step is to remove metal ions; using the EDTA chelating agent-assisted method, the jujube dregs sample obtained in the previous step is added to a 0.05mol/L EDTA solution, so that the liquid-solid ratio is 24 L: 1kg, and the extraction temperature is 35 ° C. Time 3-4h, get the extract; The third step is multi-enzyme step-by-step extraction; firstly, carry out enzymatic hydrolysis with cellulase and hemicellulose compound enzyme, and then carry out the enzymatic hydrolysis of the above extract with cellulase and hemicellulose compound enzyme. The enzymatic hydrolysis conditions are: use cellulose Enzyme: compound enzyme mixed with hemicellulase 1.2:1, temperature 45°C, pH 4.5, enzyme dosage 0.8% of the quality of the extract, extraction time 4-5h, to obtain a reaction solution; Then carry out protease and lipase compound enzymatic hydrolysis, adjust the temperature of the reaction solution to 55°C, pH6, add papain and lipase to the reaction solution in a ratio of 1:1, the total amount of enzyme is 1.0% of the mass of the reaction solution %, the extraction time is 3-4h, and the pectin enzymatic hydrolysis solution is obtained; The fourth step is centrifugation; the pectin enzymatic hydrolysis solution obtained in the third step is centrifuged at 15000r/min for 5min to remove insoluble matter and enzyme agent to obtain a pectin extract; The fifth step is decolorization; the processed D900 type decolorization resin is loaded into a chromatographic column with a specification of 600mm × 50mm, and the loading amount is 2/3 of the height of the column, and the pH value is adjusted to 6 for subsequent use, and the fourth step is obtained The pectin extract solution is decolorized by resin at a flow rate of 200mL/h at room temperature, and the decolorized pectin extract solution is collected for subsequent use; The sixth step is to concentrate; use 5 kinds of ultrafiltration membrane modules with molecular weight cut-offs of 300KD, 100KD, 30KD, 10KD, and 5KD to separate pectin, and extract the pectin after decolorization under room temperature, inlet pressure 70kPa, and outlet pressure 30kPa Through the circulation pump, it is input into the membrane modules with molecular weight cut off in order from large to small, and after ultrafiltration and separation, six parts of pectin sample liquids greater than 300KD, 300KD-100KD, 100KD-30KD, 30KD-10KD, 10KD-5KD and less than 5KD are obtained. ; The seventh step is drying; use a spray dryer to dry, spray and dry pectin sample liquids of different components at 130°C to 160°C instantaneously to obtain pectin products with different molecular weights; the dried products are sieved through a 60-mesh sieve, That is, different molecular weight pectin powders are obtained. 2. a kind of method that utilizes degradation solubilization technology to extract and prepare jujube pectin from jujube dregs according to claim 1, is characterized in that, select the pectin separated by the ultrafiltration membrane module more than 100KD, obtain molecular weight greater than 100KD Jujube pectin finished product. 3. A method of extracting and preparing jujube pectin from jujube dregs by utilizing degradation solubilization technology according to claim 1, characterized in that concentrated jujube pectin is mainly concentrated in the large molecular weight part, and more than 100KD part reaches 90% above. 4. A method of extracting and preparing jujube pectin from jujube dregs using degradation and solubilization technology according to claim 1, wherein the molecular weight is greater than 300KD and accounts for more than 78.24%, and the part of 300KD-100KD accounts for more than 14.31% . 5. A method of extracting and preparing jujube pectin from jujube dregs using degradation and solubilization technology according to claim 2, characterized in that the finished product of jujube pectin is light yellow or light brown powder, and the weight loss is reduced by drying 5.43 w%±0.12, sulfur dioxide: 32.21 mg/kg±0.24, acid-insoluble ash: 0.73 w%±0.03, total galacturonic acid: 89.96 w%±0.64, lead: 0.35 mg/kg±0.02.