阅读说明：本技术 一种亚临界萃取茶籽油的方法 (Subcritical tea seed oil extraction method ) 是由 商亚芳 魏兆军 曾嘉 苗俊豪 支霜霜 冯坤 田逸豪 张盛阳 孙冬 王玉平 于 2020-12-07 设计创作，主要内容包括：本发明公开了一种亚临界萃取茶籽油的方法,包括以下步骤：(1)将茶籽原材料进行粉碎处理,得到茶籽粉；(2)将茶籽粉进行加热处理,或在茶籽粉中加入中性蛋白酶或中性蛋白酶的水溶液后,进行加热处理,得到茶籽亚临界萃取的原材料；(3)将步骤2所得材料与亚临界提取液混合进行亚临界提取得到茶籽油；(4)将上述茶籽油离心分离,取上清液,即得亚临界萃取的茶籽油。本发明采用在茶籽中加入中性蛋白酶或其水溶液、加热茶籽,均能有效提高亚临界对茶籽油的萃取率,且加入中性蛋白酶能够有效降低茶籽油中的过氧化值,同时萃取溶剂正丁烷可以回收重新利用,非常适合工业化生产。(The invention discloses a subcritical tea seed oil extraction method, which comprises the following steps: (1) crushing a tea seed raw material to obtain tea seed powder; (2) heating tea seed powder, or adding neutral protease or aqueous solution of neutral protease into tea seed powder, and heating to obtain subcritical extraction raw material of tea seed; (3) mixing the material obtained in the step (2) with a subcritical extracting solution, and performing subcritical extraction to obtain tea seed oil; (4) and (3) centrifugally separating the tea seed oil, and taking supernatant to obtain the subcritical extracted tea seed oil. According to the invention, neutral protease or the aqueous solution thereof is added into the tea seeds, the tea seeds are heated, the subcritical extraction rate of the tea seed oil can be effectively improved, the neutral protease is added, the peroxide value in the tea seed oil can be effectively reduced, and the n-butane serving as an extraction solvent can be recycled, so that the method is very suitable for industrial production.)

1. The subcritical tea seed oil extraction method is characterized by comprising the following steps of:

(1) crushing a tea seed raw material to obtain tea seed powder;

(2) heating tea seed powder, or adding neutral protease or aqueous solution of neutral protease into tea seed powder, and heating to obtain subcritical extraction raw material of tea seed;

(3) mixing the material obtained in the step (2) with a subcritical extracting solution, and performing subcritical extraction to obtain tea seed oil;

(4) and (3) centrifugally separating the tea seed oil, and taking supernatant to obtain the subcritical extracted tea seed oil.

2. The subcritical tea seed oil extraction method according to claim 1, wherein the temperature for the pulverization treatment in the step 1 is 25-28 ℃, and the size of the pulverized particles is 20-120 meshes.

3. The method for subcritical extraction of tea seed oil according to claim 2, wherein the size of the crushed particles is 20-60 mesh.

4. The method for subcritical extraction of tea seed oil according to claim 1, wherein the heating temperature in the step 2 is 40-80 ℃ and the time is not more than 2 hours.

5. The method for subcritical extraction of tea seed oil according to claim 4, wherein the heating temperature is 50-70 ℃ and the time is 1-1.5 hours.

6. The subcritical tea seed oil extraction method according to claim 1, wherein neutral protease is added in the step 2, and the addition amount is more than 0 and less than or equal to 4% by mass.

7. The method for subcritical extraction of tea seed oil according to claim 1, wherein the aqueous solution of neutral protease is added in the step 2, and the addition amount is more than 0% and less than or equal to 4% by mass.

8. The method for subcritical extraction of tea seed oil according to claim 6 or 7, characterized in that the addition amount of neutral protease is 0 < neutral protease.ltoreq.2% by mass, and the addition amount of the aqueous solution of neutral protease is 0 < neutral protease.ltoreq.2% by mass.

9. The method for subcritical extraction of tea seed oil according to claim 1, wherein the subcritical extraction liquid in the step 3 is n-butane, and the mass-to-volume ratio of the raw material for subcritical extraction of tea seed to n-butane is 1: (0.05-0.25) g/L, subcritical extraction temperature in extraction process is 40 deg.C, vacuum concentration temperature is 30-50 deg.C, extraction time is 20-60min, and extraction pressure is 0.1 MPa.

10. The method for subcritical extraction of tea seed oil according to claim 9, wherein the mass volume ratio of the raw material for subcritical extraction of tea seed to n-butane is 1: 0.25g/L, subcritical extraction temperature of 40 deg.C, vacuum concentration temperature of 40 deg.C, extraction time of 30-40min, and extraction pressure of 0.1 MPa.

Technical Field

The invention belongs to the technical field of tea seed oil extraction, and particularly relates to a subcritical tea seed oil extraction method.

Background

Tea seeds, called 'east olive oil', are a peculiar species in China, have unsaturated fatty acids of more than 90 percent, oleic acid of 80-83 percent, linoleic acid of 7-13 percent and palmitic acid of 8-10 percent, and contain specific physiological active substances which are not contained in the olive oil, such as camellin, tea polyphenol and the like, have the oxidation resistance, and can reduce blood pressure, blood fat and arteriosclerosis. The current tea seed oil extraction methods commonly used in industry mainly comprise a squeezing method, a leaching method and an organic solvent extraction method, and the application of a subcritical extraction method is not wide.

Subcritical extraction is a novel extraction and separation technology which utilizes subcritical fluid as an extractant, transfers fat-soluble components in solid materials to a liquid extractant through a molecular diffusion process of the extraction materials and the extractant in a soaking process in a closed, oxygen-free and low-pressure container according to the principle that organic matters are similar, and separates the extractant from a target product through a reduced pressure evaporation process to finally obtain the target product. The tea seed oil obtained by subcritical extraction is non-toxic and harmless, is environment-friendly, is pollution-free, is not subjected to thermal processing, keeps the active ingredients of the extract, is not damaged or oxidized, has high capacity, can be industrially produced in a large scale, is energy-saving, has low operation cost, is easy to separate from the product, and can not reach an ideal index on the extraction efficiency.

Disclosure of Invention

The invention aims to make up for the defects of the prior art and provides a subcritical tea seed oil extraction method to improve the extraction efficiency of the conventional subcritical tea seed oil extraction method.

In order to achieve the above object, the present invention provides the following technical solutions:

a subcritical tea seed oil extraction method comprises the following steps:

(1) crushing a tea seed raw material to obtain tea seed powder;

(2) heating tea seed powder, or adding neutral protease or aqueous solution of neutral protease into tea seed powder, and heating to obtain subcritical extraction raw material of tea seed;

(3) mixing the material obtained in the step (2) with a subcritical extracting solution, and performing subcritical extraction to obtain tea seed oil;

(4) and (3) centrifugally separating the tea seed oil, and taking supernatant to obtain the subcritical extracted tea seed oil.

Further, the temperature of the crushing treatment in the step 1 is 25-28 ℃, the size of the crushed particles is 20-120 meshes, preferably, the size of the crushed particles is 20-60 meshes, and more preferably, 20-40 meshes.

Further, in the step 2, the heating temperature is 40-80 ℃ and the time is not more than 2 hours, preferably, the heating temperature is 50-70 ℃ and the time is 1-1.5 hours, and more preferably, the heating temperature is 50 ℃ and the time is 1 hour.

Further, neutral protease is added in the step 2, and the addition amount is more than 0 and less than or equal to 4 percent by mass.

Further, the step 2 is to add the water solution of neutral protease, and the addition amount of the water solution of neutral protease is more than 0% and less than or equal to 4% by mass percent.

Preferably, the adding amount of the neutral protease is more than 0 and less than or equal to 2 percent by mass percent, and the adding amount of the aqueous solution of the neutral protease is more than 0 and less than or equal to 2 percent by mass percent.

More preferably, the adding amount of the neutral protease is more than 0 and less than or equal to 1 percent by mass percent, and the adding amount of the aqueous solution of the neutral protease is more than 0 and less than or equal to 1 percent by mass percent.

Further, in the step 3, the subcritical extracting solution is n-butane, and the mass-to-volume ratio of the raw material for subcritical extraction of the tea seeds to the n-butane is 1: (0.05-0.25) g/L, subcritical extraction temperature in extraction process is 40 deg.C, vacuum concentration temperature is 30-50 deg.C, extraction time is 20-60min, and extraction pressure is 0.1 MPa.

Preferably, the mass-to-volume ratio of the raw material for subcritical extraction of tea seeds to n-butane is 1: 0.25g/L, subcritical extraction temperature of 40 deg.C, vacuum concentration temperature of 40 deg.C, extraction time of 30-40min, preferably 30min, and extraction pressure of 0.1 MPa.

Further, the centrifugation conditions in the step 4 are as follows: the rotation speed is not less than 5000r/min, preferably 10000r/min, and the centrifugation time is 5 min.

Furthermore, the extraction rate of the obtained tea seed oil reaches 25-34%, the tea seed oil contains 8-10% of palmitic acid and 80-85% of oleic acid, and the peroxide value is (0.06-0.12) g/100 g.

The inventor surprisingly discovers that by carrying out preheating treatment on tea seeds, the tissue structure of the tea seeds can be damaged through thermal reaction, and the oil yield of the tea seeds can be improved; by directly adding neutral protease to treat the tea seed sample, the oil yield of the tea seeds can be improved, and the peroxide value of the tea seed oil is obviously reduced; by adding neutral protease aqueous solution to treat a tea seed sample, drying treatment is carried out after reaction, so that the extraction rate of tea seed oil in a sub-critical way can be increased.

The invention has the advantages that:

1. the oil yield of the tea seed oil extracted by the invention can reach 118.1%, and the extract contains 8.06% of palmitic acid, 1.66% of stearic acid, 81.8% of oleic acid, 7.66% of linoleic acid, 0.065% of palmitoleic acid, 0.0504% of methyl heptadecacarbonate, 0.0536% of cis-10-methyl heptadecaenoate, 0.624% of alpha-linolenic acid and 0.0517% of cis-15-methyl tetracosanenoate. According to the invention, the peroxidation value of the tea seed oil of the tea seed sample subjected to heating treatment after the neutral protease is added is reduced to 0.069g/100g from 0.12g/100g of a control group, so that the oxidation degree of the grease is obviously reduced.

2. The oil yield of the tea seed oil can be obviously improved by the neutral protease and the heating treatment process, and the oil yield is increased from 97.2% to 118.1% of a control group.

3. According to the invention, neutral protease or the aqueous solution thereof is added into the tea seeds, the tea seeds are heated, the subcritical extraction rate of the tea seed oil can be effectively improved, the neutral protease is added, the peroxide value in the tea seed oil can be effectively reduced, and the n-butane serving as an extraction solvent can be recycled, so that the method is very suitable for industrial production.

Detailed Description

The technical scheme of the invention is further explained by combining the specific examples as follows:

the examples use raw materials and equipment:

tea seed: the oil content of tea seed kernels detected by the national standard method (GB/T5512-85) of Changlin series tea seeds provided by the great-block agriculture shares Co., Ltd, Liuan City, Anhui province is 48%, namely the average oil content in the obtained 20g of tea seed test products is 5.76 g.

A constant-temperature water bath kettle: jintan jie jerry electrical limited, model: HH-2 digital display constant temperature water bath.

Subcritical extraction equipment: critical biotechnology limited in south river asia, type: CBE-5L.

A centrifuge: saimer Feishale science and technology (China) Inc., model number Multifuge X1.

Example 1

(1) Grinding tea seeds into powder (20 meshes), taking 20g of tea seed powder and 0.1g of protease, uniformly mixing, and placing in a beaker;

(2) performing subcritical extraction with n-butane as extraction medium for 30min, and desolventizing to desolventizing pressure below 0.1MPa to obtain crude oil;

(3) placing the crude oil in a centrifuge tube, and centrifuging at 10000r/min for 5min to obtain crude oil supernatant;

(4) weighing the crude oil supernatant, and recording data;

the oil yield of the obtained tea seeds is 5.8g, the extraction rate is 29 percent,

example 2

(1) Grinding tea seeds into powder (20 meshes), taking 20g of tea seed powder and 0.15g of protease, uniformly mixing, and placing in a beaker;

(2) performing subcritical extraction with n-butane as extraction medium for 30min, and desolventizing to desolventizing pressure below 0.1MPa to obtain crude oil;

(3) placing the crude oil in a centrifuge tube, and centrifuging at 10000r/min for 5min to obtain crude oil supernatant;

(4) weighing the crude oil supernatant, and recording data;

the obtained tea seed has oil yield of 6.0g and extraction rate of 30%,

example 3

(1) Grinding tea seeds into powder of 20 meshes), putting 20g of tea seed powder into a beaker, and sealing the beaker by using a preservative film;

(2) putting the beaker into a water bath at 50 ℃, and heating for 30 min;

(3) recovering the tea seed powder to room temperature, performing subcritical extraction with n-butane as extraction medium for 30min, and desolventizing to desolventizing pressure below 0.1MPa to obtain crude oil;

(4) after extraction, placing the crude oil in a centrifuge tube, and carrying out centrifugation treatment for 5min at a rotation speed of 10000r/min to obtain crude oil supernatant;

(5) weighing the crude oil supernatant, and recording data;

the obtained tea seed has oil yield of 6.5g and extraction rate of 32.5%,

example 4

(1) Grinding tea seeds into powder (20 meshes), putting 20g of tea seed powder into a beaker, and sealing the beaker by using a preservative film;

(2) putting the beaker into a water bath at 50 ℃, and heating for 60 min;

(3) recovering the tea seed powder to room temperature, performing subcritical extraction with n-butane as extraction medium for 30min, and desolventizing to desolventizing pressure below 0.1MPa to obtain crude oil;

(4) placing the crude oil in a centrifuge tube for centrifuging at a rotation speed of 10000r/min for 5min to obtain crude oil supernatant;

(5) weighing the crude oil supernatant, and recording data;

the obtained tea seed has oil yield of 6.8g and extraction rate of 34%,

example 5

(1) Grinding tea seeds into powder (20 meshes), uniformly mixing 20g of tea seed powder and 0.1g of protease, placing the mixture into a beaker, and sealing the beaker by using a preservative film;

(2) putting the beaker into a water bath at 50 ℃, and heating for 60 min;

(3) recovering the tea seed powder to room temperature, performing subcritical extraction with n-butane as extraction medium for 30min, and desolventizing to desolventizing pressure below 0.1MPa to obtain crude oil;

(4) after extraction, placing the crude oil in a centrifuge tube, and carrying out centrifugation treatment for 5min at a rotation speed of 10000r/min to obtain crude oil supernatant;

(5) weighing the crude oil supernatant, and recording data;

obtained byThe oil yield of the tea seeds is 6.8g, the extraction rate is 34 percent,

example 6

(1) Grinding tea seeds into powder (20 meshes), taking 20g of tea seed powder, mixing 0.1g of protease and 4mL of distilled water in a centrifuge tube to obtain a mixed solution, placing the tea seed powder in a beaker, and sealing the beaker by using a preservative film;

(2) putting the beaker and the centrifuge tube into a water bath at 50 ℃, and heating for 60min in the water bath;

(3) mixing the mixed solution with tea seed powder, placing into water bath, and heating in water bath for 60 min;

(4) placing the mixture after the water bath into a plate, flattening, and placing the plate into a drying oven for drying at 50 ℃ for 1.5 h;

(5) recovering the tea seed powder to room temperature, performing subcritical extraction with n-butane as extraction medium for 30min, and desolventizing to desolventizing pressure below 0.1MPa to obtain crude oil;

(6) and after extraction, placing the crude oil in a centrifuge tube for centrifugal treatment. Centrifuging for 5min at 10000r/min to obtain crude oil supernatant;

(7) weighing the crude oil supernatant, and recording data;

the obtained tea seed has oil yield of 5.5g and extraction rate of 27.5%,

example 7

(1) Grinding tea seeds into powder (20 meshes), taking 20g of tea seed powder, mixing 0.1g of protease and 4ml of distilled water in a centrifugal tube to obtain a mixed solution, placing the tea seed powder in a beaker, and sealing the beaker by using a preservative film;

(2) preheating a water bath kettle, putting a beaker and a centrifuge tube into the water bath kettle when the temperature reaches about 50 ℃, and heating in a water bath for 60 min;

(3) mixing the mixed solution with tea seed powder, placing into water bath, and heating in water bath for 120 min;

(4) placing the mixture after the water bath into a plate, flattening, and placing the plate into a drying oven for drying for 1 h;

(5) recovering the tea seed powder to room temperature, performing subcritical extraction with n-butane as extraction medium for 30min, and desolventizing to desolventizing pressure below 0.1 MPa;

(6) and after extraction, placing the crude oil in a centrifuge tube for centrifugal treatment. Centrifuging for 5min at 10000r/min to obtain crude oil supernatant;

(7) weighing the tea seed oil, and recording data;

the obtained tea seed has oil yield of 5.9g, extraction rate of 29.5%,

comparative example

The comparative example is similar to example 1 except that, without the enzyme addition or heating process described in step (1), the tea seed powder at room temperature was directly subjected to the subcritical extraction of step (2), and the extraction rate of tea seeds was 28% and the oil yield was 97.2%.

The crude oil supernatants of examples 5 and 7 and comparative example above were subjected to peroxide number measurements, respectively: 0.069g/100g, 0.12g/100g, 0.12g/100 g. The result shows that the peroxidation of the tea seed oil can be effectively reduced by singly adding the enzyme to treat the tea seeds, the oxidation degree of fatty acid in the oil is reduced, and the quality of the tea seed oil is effectively improved. The peroxide value of the tea seed oil obtained by adding water and adding enzyme is the same as that of the tea seed oil obtained by adding water and adding enzyme, probably because the action of protease is counteracted by adding water, and the specific mechanism needs to be further discussed.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.