阅读说明：本技术 一种从茶叶提取高纯度茶多酚的工艺 (Process for extracting high-purity tea polyphenol from tea leaves ) 是由 不公告发明人 于 2021-08-18 设计创作，主要内容包括：本发明公开了一种从茶叶提取高纯度茶多酚的工艺,属于食品工业技术领域。它包括以下步骤：(1)收集茶叶渣,加清水冲洗干净后,自然晾干,待用；(2)将步骤(1)中自然晾干后的茶叶渣,进行研磨制粉,得到茶叶粉,待用；(3)将步骤(2)中得到的茶叶粉倒入料液槽中,并加入有机萃取剂,水浴处理后,得到萃取液,待用；(4)将步骤(3)得到的萃取液进行冷却,并进行离心沉淀处理,取上清液,待用；(5)将步骤(4)取到的上清液进行树脂吸附处理,随后喷雾干燥处理,即得。本发明充分利用茶叶渣,合理设置有机萃取剂的比例关系,设置乙醇、丙酮、乙酸乙酯三种物质混合进行萃取,并优化树脂吸附处理方法,使得制备的茶多酚满足需求。(The invention discloses a process for extracting high-purity tea polyphenol from tea leaves, and belongs to the technical field of food industry. It comprises the following steps: (1) collecting tea leaves, adding clear water, washing, and naturally drying; (2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use; (3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use; (4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use; (5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product. The method fully utilizes the tea leaves, reasonably sets the proportion relation of the organic extracting agent, mixes the three substances of ethanol, acetone and ethyl acetate for extraction, and optimizes the resin adsorption treatment method, so that the prepared tea polyphenol meets the requirements.)

1. A process for extracting high-purity tea polyphenol from tea leaves is characterized by comprising the following steps:

the method comprises the following steps:

(1) collecting tea leaves, adding clear water, washing, and naturally drying;

(2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use;

(3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use;

(4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use;

(5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product.

2. The process of extracting high purity tea polyphenols from tea leaves as claimed in claim 1, wherein:

the tea variety of the tea residue in the step (1) is Yuexi Cuilan.

3. The process of extracting high purity tea polyphenols from tea leaves as claimed in claim 1, wherein:

the average particle size of the tea powder in the step (2) is 100 meshes.

4. The process of extracting high purity tea polyphenols from tea leaves as claimed in claim 1, wherein:

the organic extracting agent in the step (3) comprises ethanol, acetone and ethyl acetate;

wherein the volume ratio of ethanol, acetone and ethyl acetate is 1: 5: 1.

5. the process of extracting high purity tea polyphenols from tea leaves as claimed in claim 4, wherein:

in the step (3), the mass-volume ratio of the tea powder to the organic extractant is 1: (30-50).

6. The process of extracting high purity tea polyphenols from tea leaves as claimed in claim 5, wherein:

the temperature of the water bath treatment in the step (3) is 37 ℃;

the time of the water bath treatment in the step (3) is 4 h.

7. The process of extracting high purity tea polyphenols from tea leaves as claimed in claim 1, wherein:

the cooling temperature in the step (4) is 4 ℃;

continuously stirring in the cooling process in the step (4);

the rotation speed of the stirring treatment in the step (4) was 200 rpm.

8. The process of extracting high purity tea polyphenols from tea leaves as claimed in claim 7, wherein:

the temperature of centrifugal precipitation in the step (4) is 4 ℃;

the rotation speed of the centrifugal precipitation in the step (4) is 12000 rpm.

9. The process of extracting high purity tea polyphenols from tea leaves as claimed in claim 1, wherein:

the resin subjected to resin adsorption treatment in the step (5) is a styrene-divinylbenzene polymer, wherein the dosage ratio of styrene to divinylbenzene is 2: 3, the average pore diameter is 260nm-320nm, the specific surface area is 110m²/g-115m²/g。

10. The process of extracting high purity tea polyphenols from tea leaves as claimed in claim 9, wherein:

the effluent liquid after the resin adsorption treatment in the step (5) needs to be subjected to ultracentrifugation treatment, wherein the centrifugal force is 30000g, and the centrifugation temperature is 4 ℃.

Technical Field

The invention belongs to the technical field of food industry, and particularly relates to a process for extracting high-purity tea polyphenol from tea.

Background

Tea polyphenols are the general name of polyphenols in tea, and are white amorphous powder, which are easily soluble in water, soluble in ethanol, methanol, acetone, ethyl acetate, and insoluble in chloroform. The green tea has high tea polyphenol content accounting for 15-30% of the weight, and the tea polyphenol comprises the following main components: flavanones, anthocyanidins, flavonols, anthocyanins, phenolic acids and depside 6 compounds. Wherein, flavanones (mainly catechin compounds) are the most important and account for 60 to 80 percent of the total amount of tea polyphenol, and flavonoids and other phenolic substances are less.

At present, the extraction process of tea polyphenol is more, and the process comprises the following specific steps:

organic solvent extraction method

This is one of the most widely used methods. The principle is to extract and separate different compounds in tea by utilizing the solubility difference of different solvents. The method is simple, and the extraction rate of the tea polyphenol is 10-15%. The process flow comprises the following steps: tea → extraction with boiling water → filtration → filtrate → extraction with chloroform → extraction with ethyl acetate → concentrated drying → crude GTP; or directly extracting with ethanol, propanol, toluene, etc., but the effect is not good, and the steps are complicated.

The process has the following defects: a plurality of organic solvents are used in the whole production process, and the using amount of the organic solvents is large; the process is complex, the process is complicated, multiple times of distillation are needed, the heating time is too long, and the tea polyphenol is easy to oxidize; most of the solvents such as chloroform and the like with certain toxicity are used, and the products and the operation are not safe enough; the production cost is high.

Ion precipitation extraction method

The method mainly utilizes some metal ions to precipitate tea polyphenol so as to separate the tea polyphenol from caffeine. The method is characterized in that: after the tea is leached by hot water, a precipitator is added to obtain crystalline precipitates of tea polyphenol and metal ions, the leaching liquor does not need to be concentrated, the energy consumption can be reduced to a certain extent, meanwhile, because the selectivity of the precipitates is high, the purity of the product can relatively better reach more than 85 percent, but the loss of the tea polyphenol is large in the subsequent dilute acid conversion and dissolution process, and some precipitants are metal ions with certain toxicity, and some precipitants are alkaline and easily cause the oxidation of the tea polyphenol. Therefore, the purity, yield, cost and safety of the product are not yet fully satisfactory.

The process flow comprises the following steps: tea → extraction in boiling water → filtration → filtrate → precipitation of precipitant → solubilization → extraction → concentrated drying → crude GTP.

Adsorption separation extraction method

Extracting green tea powder with hot water for 3 times, and mixing extractive solutions. Adsorbing the tea extractive solution with polymeric adsorbent, eluting with 95% ethanol solution to desorb GTP adsorbed on the adsorbent in ethanol, distilling under reduced pressure to recover ethanol, and vacuum drying or spray drying the concentrated solution to obtain tea polyphenols. The method has simple process and low energy consumption, but needs an adsorbent with strong GTP selectivity and high adsorption capacity.

The process flow comprises the following steps: tea → extraction in boiling water → filtration → filtrate → resin → eluent → concentrated drying → GTP.

Supercritical fluid extraction

Supercritical Fluid Extraction (SFE) is a new separation technique, which uses a fluid with a temperature and pressure slightly higher than or close to the critical temperature and critical pressure between gas and liquid as an extractant to extract certain high-boiling point and heat-sensitive components from solid or liquid for separation and purification purposes. The medium is usually nontoxic carbon dioxide, so that the product is not toxic, and the method is particularly suitable for extracting products such as medicines, food additives and the like. Compared with the common extraction separation technology, the supercritical fluid extraction technology has the advantages of excellent transfer performance, stronger osmotic force, good selectivity, high solubility to organic matters, high extraction rate, good product quality, mild operation conditions, particular suitability for separating heat-sensitive substances and the like.

The process flow comprises the following steps: and (3) extracting the tea dust by SFE → purifying tea polyphenol crude product → GTP with high purity.

Ultrasonic leaching method

The ultrasonic extraction method utilizes the mechanical crushing and cavitation of ultrasonic waves to accelerate the diffusion rate of tea polyphenol and other extracts from tea leaves to a solvent and shorten the extraction time, and the extract is treated and refined in the same way as the traditional process to obtain the product. From the reported results, it can be seen that the effect of leaching for not more than one hour under the action of ultrasonic irradiation is comparable to the effect of conventional leaching for several hours. The traditional process has long extraction time no matter using water or organic solvent, and the tea polyphenol is easy to be oxidized under the condition of high humidity, so the quality is reduced, and the yield is reduced; the ultrasonic extraction has the greatest advantage that the extraction time is short, so that the oxidation of tea polyphenol under high temperature for a long time is avoided, and the yield and the product quality are higher than those of the traditional method.

Microwave leaching method

The microwave extraction method is a new method which is just started in recent years, and the basic principle is that the high-frequency movement of molecules in a microwave field is utilized, so that the diffusion rate is increased, and therefore, the extracts such as tea polyphenol and the like can be quickly extracted under the radiation action of microwaves. Microwave-assisted extraction is utilized, and the effect of traditional extraction for hours can be achieved only by one time of minutes. Therefore, the oxidation of tea polyphenol at high temperature for a long time is greatly reduced, and the quality and the yield of the product are improved. The microwave technology applied to the extraction of tea polyphenol has the advantages of short time, high efficiency, energy conservation and the like. The microwave and water bath extraction has high tea polyphenol leaching rate superior to that of ethanol and water extraction, low cost and less pollution.

However, the above method is single and expensive, and cannot meet the requirements of laboratories or small factories.

Disclosure of Invention

1. Problems to be solved

Aiming at the problems in the prior art, the invention provides a process for extracting high-purity tea polyphenol from tea leaves, which is simple, and particularly, the prepared tea polyphenol meets the use requirement.

2. Technical scheme

In order to solve the above problems, the present invention adopts the following technical solutions.

A process for extracting high-purity tea polyphenol from tea leaves comprises the following steps:

(1) collecting tea leaves, adding clear water, washing, and naturally drying;

(2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use;

(3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use;

(4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use;

(5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product.

In the process for extracting high-purity tea polyphenol from tea leaves, the tea variety of the tea leaves in the step (1) is Yuexi Cuilan.

In the process for extracting high-purity tea polyphenol from tea leaves, the average particle size of the tea powder in the step (2) is 100 meshes.

In the process for extracting high-purity tea polyphenol from tea leaves, the organic extracting agent in the step (3) comprises ethanol, acetone and ethyl acetate;

wherein the volume ratio of ethanol, acetone and ethyl acetate is 1: 5: 1.

in the process for extracting high-purity tea polyphenol from tea leaves, the mass-to-volume ratio of the tea powder to the organic extracting agent in the step (3) is 1: (30-50).

In the process for extracting high-purity tea polyphenol from tea leaves, the temperature of water bath treatment in the step (3) is 37 ℃;

the time of the water bath treatment in the step (3) is 4 h.

In the process for extracting high-purity tea polyphenol from tea leaves, the cooling temperature in the step (4) is 4 ℃;

continuously stirring in the cooling process in the step (4);

the rotation speed of the stirring treatment in the step (4) was 200 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the temperature of centrifugal precipitation in the step (4) is 4 ℃;

the rotation speed of the centrifugal precipitation in the step (4) is 12000 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the resin subjected to resin adsorption treatment in the step (5) is a styrene-divinylbenzene polymer, wherein the dosage ratio of styrene to divinylbenzene is 2: 3, the average pore diameter is 260nm-320nm, the specific surface area is 110m²/g-115m²/g。

In the above process for extracting high-purity tea polyphenol from tea leaves, the effluent liquid after the resin adsorption treatment in the step (5) needs to be subjected to ultracentrifugation treatment, wherein the centrifugal force is 30000g, and the centrifugation temperature is 4 ℃.

3. Advantageous effects

Compared with the prior art, the invention has the beneficial effects that:

the tea polyphenol obtained by the extraction process is mainly used in laboratories or small factories, and the purity of the tea polyphenol can meet the requirements. Compared with the traditional technology, the method has the advantages that the tea leaves of Yuexi Cuilan are fully utilized, the proportion relation of the organic extracting agent is reasonably set, three substances of ethanol, acetone and ethyl acetate are mixed for extraction, and the resin adsorption treatment method is optimized, so that the prepared tea polyphenol meets the requirements.

Detailed Description

The invention is further described with reference to specific examples.

Example 1

Best mode for carrying out the invention

The process for extracting high-purity tea polyphenol from tea leaves comprises the following steps:

(1) collecting tea leaves, adding clear water, washing, and naturally drying;

(2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use;

(3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use;

(4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use;

(5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product.

In the process for extracting high-purity tea polyphenol from tea leaves, the tea variety of the tea leaves in the step (1) is Yuexi Cuilan.

In the process for extracting high-purity tea polyphenol from tea leaves, the average particle size of the tea powder in the step (2) is 100 meshes.

In the process for extracting high-purity tea polyphenol from tea leaves, the organic extracting agent in the step (3) comprises ethanol, acetone and ethyl acetate;

wherein the volume ratio of ethanol, acetone and ethyl acetate is 1: 5: 1.

in the process for extracting high-purity tea polyphenol from tea leaves, the mass-to-volume ratio of the tea powder to the organic extracting agent in the step (3) is 1: 40.

in the process for extracting high-purity tea polyphenol from tea leaves, the temperature of water bath treatment in the step (3) is 37 ℃;

the time of the water bath treatment in the step (3) is 4 h.

In the process for extracting high-purity tea polyphenol from tea leaves, the cooling temperature in the step (4) is 4 ℃;

continuously stirring in the cooling process in the step (4);

the rotation speed of the stirring treatment in the step (4) was 200 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the temperature of centrifugal precipitation in the step (4) is 4 ℃;

the rotation speed of the centrifugal precipitation in the step (4) is 12000 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the resin subjected to resin adsorption treatment in the step (5) is a styrene-divinylbenzene polymer, wherein the dosage ratio of styrene to divinylbenzene is 2: 3, average pore diameter of 300nm and specific surface area of 110m²/g。

In the above process for extracting high-purity tea polyphenol from tea leaves, the effluent liquid after the resin adsorption treatment in the step (5) needs to be subjected to ultracentrifugation treatment, wherein the centrifugal force is 30000g, and the centrifugation temperature is 4 ℃.

Comparative example 1

The process for extracting high-purity tea polyphenol from tea leaves comprises the following steps:

(1) collecting tea leaves, adding clear water, washing, and naturally drying;

(2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use;

(3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use;

(4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use;

(5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product.

In the process for extracting high-purity tea polyphenol from tea leaves, the tea variety of the tea leaves in the step (1) is Yuexi Cuilan.

In the process for extracting high-purity tea polyphenol from tea leaves, the average particle size of the tea powder in the step (2) is 100 meshes.

In the process for extracting high-purity tea polyphenol from tea leaves, the organic extracting agent in the step (3) comprises ethanol, acetone and ethyl acetate;

wherein the volume ratio of ethanol, acetone and ethyl acetate is 1: 1: 1.

in the process for extracting high-purity tea polyphenol from tea leaves, the mass-to-volume ratio of the tea powder to the organic extracting agent in the step (3) is 1: 40.

in the process for extracting high-purity tea polyphenol from tea leaves, the temperature of water bath treatment in the step (3) is 37 ℃;

the time of the water bath treatment in the step (3) is 4 h.

In the process for extracting high-purity tea polyphenol from tea leaves, the cooling temperature in the step (4) is 4 ℃;

continuously stirring in the cooling process in the step (4);

the rotation speed of the stirring treatment in the step (4) was 200 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the temperature of centrifugal precipitation in the step (4) is 4 ℃;

the rotation speed of the centrifugal precipitation in the step (4) is 12000 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the resin subjected to resin adsorption treatment in the step (5) is a styrene-divinylbenzene polymer, wherein the dosage ratio of styrene to divinylbenzene is 2: 3, average pore diameter of 300nm and specific surface area of 110m²/g。

In the above process for extracting high-purity tea polyphenol from tea leaves, the effluent liquid after the resin adsorption treatment in the step (5) needs to be subjected to ultracentrifugation treatment, wherein the centrifugal force is 30000g, and the centrifugation temperature is 4 ℃.

Comparative example 2

The process for extracting high-purity tea polyphenol from tea leaves comprises the following steps:

(1) collecting tea leaves, adding clear water, washing, and naturally drying;

(2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use;

(3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use;

(4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use;

(5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product.

In the process for extracting high-purity tea polyphenol from tea leaves, the tea variety of the tea leaves in the step (1) is Yuexi Cuilan.

In the process for extracting high-purity tea polyphenol from tea leaves, the average particle size of the tea powder in the step (2) is 100 meshes.

In the process for extracting high-purity tea polyphenol from tea leaves, the organic extracting agent in the step (3) comprises ethanol, acetone and ethyl acetate;

wherein the volume ratio of ethanol, acetone and ethyl acetate is 1: 5: 1.

in the process for extracting high-purity tea polyphenol from tea leaves, the mass-to-volume ratio of the tea powder to the organic extracting agent in the step (3) is 1: 25.

in the process for extracting high-purity tea polyphenol from tea leaves, the temperature of water bath treatment in the step (3) is 37 ℃;

the time of the water bath treatment in the step (3) is 4 h.

In the process for extracting high-purity tea polyphenol from tea leaves, the cooling temperature in the step (4) is 4 ℃;

continuously stirring in the cooling process in the step (4);

the rotation speed of the stirring treatment in the step (4) was 200 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the temperature of centrifugal precipitation in the step (4) is 4 ℃;

the rotation speed of the centrifugal precipitation in the step (4) is 12000 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the resin subjected to resin adsorption treatment in the step (5) is a styrene-divinylbenzene polymer, wherein the dosage ratio of styrene to divinylbenzene is 2: 3, average pore diameter of 300nm and specific surface area of 110m²/g。

In the above process for extracting high-purity tea polyphenol from tea leaves, the effluent liquid after the resin adsorption treatment in the step (5) needs to be subjected to ultracentrifugation treatment, wherein the centrifugal force is 30000g, and the centrifugation temperature is 4 ℃.

Comparative example 3

The process for extracting high-purity tea polyphenol from tea leaves comprises the following steps:

(1) collecting tea leaves, adding clear water, washing, and naturally drying;

(2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use;

(3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use;

(4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use;

(5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product.

In the process for extracting high-purity tea polyphenol from tea leaves, the tea variety of the tea leaves in the step (1) is Yuexi Cuilan.

In the process for extracting high-purity tea polyphenol from tea leaves, the average particle size of the tea powder in the step (2) is 100 meshes.

In the process for extracting high-purity tea polyphenol from tea leaves, the organic extracting agent in the step (3) comprises ethanol, acetone and ethyl acetate;

wherein the volume ratio of ethanol, acetone and ethyl acetate is 1: 5: 1.

in the process for extracting high-purity tea polyphenol from tea leaves, the mass-to-volume ratio of the tea powder to the organic extracting agent in the step (3) is 1: 55.

in the process for extracting high-purity tea polyphenol from tea leaves, the temperature of water bath treatment in the step (3) is 37 ℃;

the time of the water bath treatment in the step (3) is 4 h.

In the process for extracting high-purity tea polyphenol from tea leaves, the cooling temperature in the step (4) is 4 ℃;

continuously stirring in the cooling process in the step (4);

the rotation speed of the stirring treatment in the step (4) was 200 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the temperature of centrifugal precipitation in the step (4) is 4 ℃;

the rotation speed of the centrifugal precipitation in the step (4) is 12000 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the resin subjected to resin adsorption treatment in the step (5) is a styrene-divinylbenzene polymer, wherein the dosage ratio of styrene to divinylbenzene is 2: 3, average pore diameter of 300nm and specific surface area of 110m²/g。

In the above process for extracting high-purity tea polyphenol from tea leaves, the effluent liquid after the resin adsorption treatment in the step (5) needs to be subjected to ultracentrifugation treatment, wherein the centrifugal force is 30000g, and the centrifugation temperature is 4 ℃.

Comparative example 4

The process for extracting high-purity tea polyphenol from tea leaves comprises the following steps:

(1) collecting tea leaves, adding clear water, washing, and naturally drying;

(2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use;

(3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use;

(4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use;

(5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product.

In the process for extracting high-purity tea polyphenol from tea leaves, the tea variety of the tea leaves in the step (1) is Yuexi Cuilan.

In the process for extracting high-purity tea polyphenol from tea leaves, the average particle size of the tea powder in the step (2) is 100 meshes.

In the process for extracting high-purity tea polyphenol from tea leaves, the organic extracting agent in the step (3) comprises ethanol and acetone;

wherein the volume ratio of ethanol to acetone is 1: 5.

in the process for extracting high-purity tea polyphenol from tea leaves, the mass-to-volume ratio of the tea powder to the organic extracting agent in the step (3) is 1: 40.

in the process for extracting high-purity tea polyphenol from tea leaves, the temperature of water bath treatment in the step (3) is 37 ℃;

the time of the water bath treatment in the step (3) is 4 h.

In the process for extracting high-purity tea polyphenol from tea leaves, the cooling temperature in the step (4) is 4 ℃;

continuously stirring in the cooling process in the step (4);

the rotation speed of the stirring treatment in the step (4) was 200 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the temperature of centrifugal precipitation in the step (4) is 4 ℃;

the rotation speed of the centrifugal precipitation in the step (4) is 12000 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the resin subjected to resin adsorption treatment in the step (5) is a styrene-divinylbenzene polymer, wherein the dosage ratio of styrene to divinylbenzene is 2: 3, average pore diameter of 300nm and specific surface area of 110m²/g。

In the above process for extracting high-purity tea polyphenol from tea leaves, the effluent liquid after the resin adsorption treatment in the step (5) needs to be subjected to ultracentrifugation treatment, wherein the centrifugal force is 30000g, and the centrifugation temperature is 4 ℃.

Comparative example 5

The process for extracting high-purity tea polyphenol from tea leaves comprises the following steps:

(1) collecting tea leaves, adding clear water, washing, and naturally drying;

(2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use;

(3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use;

(4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use;

(5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product.

In the process for extracting high-purity tea polyphenol from tea leaves, the tea variety of the tea leaves in the step (1) is Yuexi Cuilan.

In the process for extracting high-purity tea polyphenol from tea leaves, the average particle size of the tea powder in the step (2) is 100 meshes.

In the process for extracting high-purity tea polyphenol from tea leaves, the organic extracting agent in the step (3) comprises ethanol and ethyl acetate;

wherein the volume ratio of ethanol to ethyl acetate is 1: 1: 1.

in the process for extracting high-purity tea polyphenol from tea leaves, the mass-to-volume ratio of the tea powder to the organic extracting agent in the step (3) is 1: 40.

in the process for extracting high-purity tea polyphenol from tea leaves, the temperature of water bath treatment in the step (3) is 37 ℃;

the time of the water bath treatment in the step (3) is 4 h.

In the process for extracting high-purity tea polyphenol from tea leaves, the cooling temperature in the step (4) is 4 ℃;

continuously stirring in the cooling process in the step (4);

the rotation speed of the stirring treatment in the step (4) was 200 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the temperature of centrifugal precipitation in the step (4) is 4 ℃;

the rotation speed of the centrifugal precipitation in the step (4) is 12000 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the resin subjected to resin adsorption treatment in the step (5) is a styrene-divinylbenzene polymer, wherein the dosage ratio of styrene to divinylbenzene is 2: 3, average pore diameter of 300nm and specific surface area of 110m²/g。

In the above process for extracting high-purity tea polyphenol from tea leaves, the effluent liquid after the resin adsorption treatment in the step (5) needs to be subjected to ultracentrifugation treatment, wherein the centrifugal force is 30000g, and the centrifugation temperature is 4 ℃.

Comparative example 6

The process for extracting high-purity tea polyphenol from tea leaves comprises the following steps:

(1) collecting tea leaves, adding clear water, washing, and naturally drying;

(2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use;

(3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use;

(4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use;

(5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product.

In the process for extracting high-purity tea polyphenol from tea leaves, the tea variety of the tea leaves in the step (1) is Yuexi Cuilan.

In the process for extracting high-purity tea polyphenol from tea leaves, the average particle size of the tea powder in the step (2) is 100 meshes.

In the process for extracting high-purity tea polyphenol from tea leaves, the organic extracting agent in the step (3) comprises acetone and ethyl acetate;

wherein the volume ratio of acetone to ethyl acetate is 5: 1.

in the process for extracting high-purity tea polyphenol from tea leaves, the mass-to-volume ratio of the tea powder to the organic extracting agent in the step (3) is 1: 40.

in the process for extracting high-purity tea polyphenol from tea leaves, the temperature of water bath treatment in the step (3) is 37 ℃;

the time of the water bath treatment in the step (3) is 4 h.

In the process for extracting high-purity tea polyphenol from tea leaves, the cooling temperature in the step (4) is 4 ℃;

continuously stirring in the cooling process in the step (4);

the rotation speed of the stirring treatment in the step (4) was 200 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the temperature of centrifugal precipitation in the step (4) is 4 ℃;

the rotation speed of the centrifugal precipitation in the step (4) is 12000 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the resin subjected to resin adsorption treatment in the step (5) is a styrene-divinylbenzene polymer, wherein the dosage ratio of styrene to divinylbenzene is 2: 3, average pore diameter of 300nm and specific surface area of 110m²/g。

In the above process for extracting high-purity tea polyphenol from tea leaves, the effluent liquid after the resin adsorption treatment in the step (5) needs to be subjected to ultracentrifugation treatment, wherein the centrifugal force is 30000g, and the centrifugation temperature is 4 ℃.

Comparative example 7

The process for extracting high-purity tea polyphenol from tea leaves comprises the following steps:

(1) collecting tea leaves, adding clear water, washing, and naturally drying;

(2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use;

(3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use;

(4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use;

(5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product.

In the process for extracting high-purity tea polyphenol from tea leaves, the tea variety of the tea leaves in the step (1) is Yuexi Cuilan.

In the process for extracting high-purity tea polyphenol from tea leaves, the average particle size of the tea powder in the step (2) is 100 meshes.

In the process for extracting high-purity tea polyphenol from tea leaves, the organic extracting agent in the step (3) comprises ethanol, acetone and ethyl acetate;

wherein the volume ratio of ethanol, acetone and ethyl acetate is 1: 5: 1.

in the process for extracting high-purity tea polyphenol from tea leaves, the mass-to-volume ratio of the tea powder to the organic extracting agent in the step (3) is 1: 40.

in the process for extracting high-purity tea polyphenol from tea leaves, the temperature of water bath treatment in the step (3) is 37 ℃;

the time of the water bath treatment in the step (3) is 4 h.

In the process for extracting high-purity tea polyphenol from tea leaves, the cooling temperature in the step (4) is 4 ℃;

continuously stirring in the cooling process in the step (4);

the rotation speed of the stirring treatment in the step (4) was 200 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the temperature of centrifugal precipitation in the step (4) is 4 ℃;

the rotation speed of the centrifugal precipitation in the step (4) is 12000 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the resin subjected to resin adsorption treatment in the step (5) is a styrene-divinylbenzene polymer, wherein the dosage ratio of styrene to divinylbenzene is 2: 3, average pore diameter of 300nm and specific surface area of 110m²/g。

In the above process for extracting high-purity tea polyphenol from tea leaves, the effluent liquid after the resin adsorption treatment in the step (5) needs to be subjected to ultracentrifugation treatment, wherein the centrifugal force is 30000g, and the centrifugation temperature is 4 ℃.

Comparative example 8

The process for extracting high-purity tea polyphenol from tea leaves comprises the following steps:

(1) collecting tea leaves, adding clear water, washing, and naturally drying;

(2) grinding the naturally dried tea leaves in the step (1) to prepare tea powder for later use;

(3) pouring the tea powder obtained in the step (2) into a material liquid tank, adding an organic extracting agent, and performing water bath treatment to obtain an extract liquid for later use;

(4) cooling the extract obtained in the step (3), performing centrifugal precipitation treatment, and taking supernatant for later use;

(5) and (4) carrying out resin adsorption treatment on the supernatant obtained in the step (4), and then carrying out spray drying treatment to obtain the product.

In the process for extracting high-purity tea polyphenol from tea leaves, the tea variety of the tea leaves in the step (1) is Yuexi Cuilan.

In the process for extracting high-purity tea polyphenol from tea leaves, the average particle size of the tea powder in the step (2) is 100 meshes.

In the process for extracting high-purity tea polyphenol from tea leaves, the organic extracting agent in the step (3) comprises ethanol, acetone and ethyl acetate;

wherein the volume ratio of ethanol, acetone and ethyl acetate is 1: 5: 1.

in the process for extracting high-purity tea polyphenol from tea leaves, the mass-to-volume ratio of the tea powder to the organic extracting agent in the step (3) is 1: 40.

in the process for extracting high-purity tea polyphenol from tea leaves, the temperature of water bath treatment in the step (3) is 37 ℃;

the time of the water bath treatment in the step (3) is 4 h.

In the process for extracting high-purity tea polyphenol from tea leaves, the cooling temperature in the step (4) is 4 ℃;

continuously stirring in the cooling process in the step (4);

the rotation speed of the stirring treatment in the step (4) was 200 rpm.

In the process for extracting high-purity tea polyphenol from tea leaves, the temperature of centrifugal precipitation in the step (4) is 4 ℃;

the rotation speed of the centrifugal precipitation in the step (4) is 12000 rpm.

In the above process for extracting high-purity tea polyphenols from tea leaves, the resin adsorbed by the resin in step (5) is styrene, and the average value isThe pore diameter is 300nm, the specific surface area is 110m²/g。

In the above process for extracting high-purity tea polyphenol from tea leaves, the effluent liquid after the resin adsorption treatment in the step (5) needs to be subjected to ultracentrifugation treatment, wherein the centrifugal force is 30000g, and the centrifugation temperature is 4 ℃.

Example 2

The product prepared in example 1 and the products prepared in comparative examples 1 to 8 were selected and subjected to the following tests:

reference GB/T31740.2-2015 part 2 of the tea product: measuring tea polyphenol; it needs to be reminded that in the prior art, the purity of tea polyphenol can be improved in various ways, but ultrafiltration membrane or chromatographic separation is adopted, so that the production cost is high, and continuous processing is difficult.

Wherein the purity of the tea polyphenol prepared in example 1 is 95.2%;

wherein the purity of the tea polyphenol prepared in comparative example 1 is 93.0%;

wherein the purity of the tea polyphenol prepared in comparative example 2 is 94.5%;

wherein the purity of the tea polyphenol prepared in comparative example 3 is 92.7%;

wherein the purity of the tea polyphenol prepared in comparative example 4 is 68.5%;

wherein the purity of the tea polyphenol prepared in comparative example 5 is 76.2%;

wherein the purity of the tea polyphenol prepared in comparative example 6 was 70.3%;

wherein the purity of the tea polyphenol prepared in comparative example 7 is 94.8%;

wherein the purity of the tea polyphenol prepared in comparative example 8 was 91.9%.

While the invention has been described in further detail in connection with specific embodiments thereof, it will be understood that the invention is not limited thereto, and that various other modifications and substitutions may be made by those skilled in the art without departing from the spirit of the invention, which should be considered to be within the scope of the invention as defined by the appended claims.