JPH089884A - Production of extract solution of swellable dried vegetable leaf - Google Patents

Abstract

PURPOSE:To provide a method for producing an extract solution of vegetable leaves by which the extraction is efficiently and sufficiently carried out without unevenly distributing an extracting solvent in an extraction column filled with swellable dried vegetable leaves; high quality is kept without any fear of oxidizing active ingredients and the extract solution is obtained. CONSTITUTION:The method for producing an extract solution of swellable vegetable leaves is to fill the swellable dried vegetable leaves in extraction columns A, B and C so that the apparent volume in swelling thereof with an extracting solvent at the extracting temperature under normal pressures may be 1.25-5 times based on filled parts of the extraction columns and carry out the extraction in a state of the compressed swollen swellable dried vegetable leaves in a method for continuously extracting ingredients in the swellable dried vegetable leaves filled in the extraction columns with a flow of the extracting solvent and producing the extract solution.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a swellable dried plant leaf extract. More specifically, the present invention can efficiently extract the contained active ingredient from swelling dry plant leaves such as green tea, oolong tea, tea leaves such as black tea, cowberry, leaf herb drug raw materials such as datura, etc. The present invention relates to a method for producing a swellable dry plant leaf extract.

[0002]

2. Description of the Related Art Conventionally, tea leaves such as black tea, oolong tea, and green tea have been drunk by brewing or brewing with warm water or hot water each time they are consumed at home. But,
In recent years, with the diversification of tastes for beverages, containers filled with these tea leaf extract liquids such as metal cans and plastic bottles have been sold, and extraction of the active ingredient of tea leaves is a food product. It has become an important field in industry. Tea leaves such as black tea are extracted by hot water extraction or cold water extraction. As the hot water extraction, for example, a method in which tea leaves are put in a basket and immersed in hot water, or
The method of pouring hot water by putting tea leaves in a tank with a perforated bottom is performed. Extraction with hot water has the advantage that the extraction operation can be completed in a short time, but the tea leaf extract obtained by hot water extraction elutes excess tannin, etc.,
The flavor balance such as bitterness and astringency is poor, and the quality is not constant. Furthermore, when the obtained extract is cooled, a white turbidity phenomenon called cream down occurs, making it unusable for cold tea. . Japanese Patent Application Laid-Open No. 61-146150 proposes a method of adding dextrin or the like to an extract of tea leaves in order to suppress cream down. However, when a substance other than tea is mixed in the extract of tea leaves, there is a problem that the flavor peculiar to tea is impaired.
On the other hand, the tea leaf extract obtained by cold water extraction has a small degree of cream down during cooling, but is less concentrated and lacks a rich color tone as compared to the tea leaf infusion that is usually used for drinking. There was a problem that the flavor was unsatisfactory. In order to solve these problems, the present inventors first repeated cold water addition to extracted tea leaves by immersion extraction, and further repeated immersion extraction of extracted tea leaves with an extract. After that, finally, a method of extracting new leaves with an extract was proposed (JP-A-6-62738). This method makes it possible to obtain an extract of tea leaves having a high degree of concentration and an excellent color tone and flavor while effectively utilizing the advantage of the cold water extraction method that there is no cream down. It was required to further improve the flavor by extracting with. A method of packing crushed powdery particles such as coffee in an extraction tower and extracting an active ingredient by passing through an extraction solvent is widely used.
However, when attempting to extract from a relatively flat leaf-like substance such as tea leaves by such a method, the extraction solvent causes uneven flow in the extraction tower and does not flow uniformly, resulting in tea leaves that are not sufficiently extracted. The problem of remaining remains. Therefore, there has been a demand for the development of a method for producing an extract capable of efficiently and completely extracting a substance having a shape such as swelling dry plant leaves.

[0003]

DISCLOSURE OF THE INVENTION The present invention relates to swelling drying by continuously and efficiently extracting the active ingredient from a swelling dried plant leaf such as tea leaves and raw materials for herbal medicines in a closed system. The purpose of the present invention is to provide a method for producing a plant leaf extract.

[0004]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that if extraction is performed in a state where plant leaves swollen with an extraction solvent are densely packed, It has been found that the solvent can be uniformly extracted without being unbalanced, and the present invention has been completed based on this finding. That is, the present invention provides (1) a method for producing an extract by continuously extracting components in swellable dry plant leaves packed in an extraction tower with an extraction solvent flow,
The swellable dry plant leaves were placed in an extraction tower such that the apparent volume of the swellable dry plant leaves when swollen with the extraction solvent at normal pressure and extraction temperature was 1.25 to 5 times the volume of the packed part of the extraction tower. A method for producing a swellable dry plant leaf extract, characterized in that the filled and swollen swellable dry plant leaf is extracted in a compressed state, (2) The extraction tower is at the inlet side of the extraction solvent flow And a method for producing a swellable dry plant leaf extract according to item (1), which has a strainer on the outlet side,
(3) The method for producing a swellable dry plant leaf extract according to the item (2), wherein the ratio of the distance between the two strainers of the extraction tower and the diameter of the extraction tower is 0.5 / 1 to 4/1. And (4) the swellable dry plant leaves are tea leaves and the extraction solvent is water.
A method for producing the swellable dry plant leaf extract according to (1), (2) or (3).

The swellable dry plant leaf used in the method of the present invention is a leaf of a plant containing an active ingredient as a food, a drug or the like, and is in a state where most of the water is removed by drying, and the extract solvent is used. The active ingredient contained by swelling is extracted. Such swelling dry plant leaves include, for example, tea leaves such as black tea, red tea tea, oolong tea, wrapping tea, Aoyagi tea, Ureshino tea, green tea, sencha, jade green tea, and bancha, kelp, wakame, agar and the like. Seaweeds, wild plants such as kumazasa, leaf herbal medicines such as cowberry, peppermint, datura, and digitalis. The extraction solvent used in the method of the present invention is not particularly limited, and any solvent that swells swellable dry plant leaves and dissolves the active ingredient can be used.
When the active ingredient is water-soluble, it is economical to use water, and if necessary, water, monohydric alcohol such as methanol, ethanol, propanol, dihydric alcohol such as propylene glycol, glycerin, etc. 3 One of polyhydric alcohol, polyhydric alcohol such as sorbitol, monosaccharide such as glucose, polysaccharide such as sucrose, glycerin fatty acid ester, hexane, acetone, fatty acid ester, vegetable oil, animal oil, or a mixed solvent of two or more thereof. Can be used. The extraction solvent flow used in the method of the present invention is a flow of the extraction solvent that contains almost no bubbles continuously and the flow direction is not limited, but from the viewpoint of equipment design, upward flow is preferred. . In the method of the present invention, the swellable dry plant leaves are packed and extracted in an extraction tower having a strainer on the inlet side of the extraction solvent flow in the packing section. FIG. 1 is a sectional view of an example of an extraction tower used in the method of the present invention. The extraction solvent freely flows into the bottom of the extraction tower 1,
It is preferable to provide a bottom strainer 2 having a large number of holes through which plant leaves do not fall out. Extraction solvent inlet 3
The more inflowing extraction solvent fills the space under the bottom strainer of the extraction tower, then rises through the bottom strainer, and uniformly extracts the active ingredient from the swollen swelling dry plant leaf. Without a bottom strainer in the extraction tower,
If the extraction tower is directly filled with the swellable dry plant leaves, the extraction solvent flowing in through the extraction solvent inlet may be unbalanced, and plant leaves that are not sufficiently extracted may remain. The extraction column used in the method of the present invention is preferably provided with an upper strainer 4 in addition to the bottom strainer. The swollen plant leaves are held tightly packed between the bottom strainer and the top strainer and are extracted by the extraction solvent in the compressed state. Like the bottom strainer, the top strainer also has a large number of holes through which the extract can freely flow and the plant leaves do not escape. By providing the upper strainer, the plant leaf can be extracted more uniformly. The extraction liquid that has finished the extraction and flows out from the upper strainer flows out from the extraction liquid outlet 5 provided at the uppermost part of the extraction tower and is sent to the next step. An air vent port 6 is provided in the upper part of the extraction tower so that the air in the extraction tower can be vented if necessary, and the extraction tower can always be kept in a liquid-tight state. Therefore, the extract does not touch the air,
The active ingredient is not oxidized by oxygen in the air,
The quality of the extract is maintained. In the method of the present invention, it is desirable in operation that the liquid flow direction of the extraction solvent is an upward liquid flow, but it is also possible to perform extraction with a downward liquid flow after the extraction column is completely liquid-tight with the extraction solvent. Is. Furthermore, it is also possible to install the extraction tower horizontally and flow the extraction solvent horizontally for extraction. The distance L between the two strainers of the extraction column used in the process of the invention and the diameter D of the extraction column
Ratio L / D of 0.5 / 1 to 4/1, preferably 0.8 /
It is 1-3 / 1. When L / D is smaller than 1/1, the extraction solvent is liable to cause a drift, which is not preferable. When L / D exceeds 4/1, it takes time and effort to take out the plant leaves after the extraction is finished, which is not preferable.

The extraction tower used in the method of the present invention may be provided with a jacket 7 if necessary, and the extraction may be carried out at a high temperature or a low temperature. Extraction is usually -10 to 130
It is performed in the range of ° C. The extraction temperature can be approximately the temperature of the extraction liquid flowing out from the extraction tower. When the extraction is carried out at room temperature, the jacket of the extraction tower is unnecessary. In the method of the present invention, the swellable dry plant leaf has an apparent volume of the swellable dry plant leaf swelled by the extraction solvent at normal pressure and at an extraction temperature which is 1.2 times the volume of the packed portion of the extraction tower.
5 to 5 times, preferably 1.3 to 3.5 times, and more preferably 1.4 to 2.5 times. When the extraction column has only a strainer on the inlet side of the extraction solvent flow in the packing unit, the volume of the packed portion of the extraction column is from the strainer on the inlet side of the extraction solvent flow to the volume of the extraction column in the extraction solvent flow direction, and the extraction is also performed. When having a strainer on the inlet side and a strainer on the outlet side of the solvent flow, it corresponds to the volume between the two strainers. The apparent volume of the swellable dry plant leaves when swollen with the extraction solvent at normal pressure and the extraction temperature was determined by swelling a certain amount of the swellable dry plant leaves in the extraction solvent until they reached equilibrium. After that, by pouring into a measuring container equipped with a strainer at the bottom of which the extraction solvent flows out, the apparent volume of the swollen dry plant leaf can be known. The apparent volume of the swelling dry plant leaves to be packed in the extraction tower when swelled with the extraction solvent at the normal pressure and the extraction temperature is 1.25 of the volume of the packed portion of the extraction tower.
If it is less than twice, the extraction solvent may cause a nonuniform flow, and the active ingredient of the swellable dry plant leaf may not be uniformly extracted, which is not preferable. If the apparent volume of the swellable dry plant leaves to be packed in the extraction tower when swelled with the extraction solvent at normal pressure and extraction temperature exceeds 5 times the volume of the packed part of the extraction tower, extraction of the active ingredient with the extraction solvent will occur. This is not preferable because the effect is reduced, the pressure loss in the circulation of the extraction solvent is large, and sometimes the strainer is deformed due to the pressure due to the swelling of the swelling dry plant leaf. In the method of the present invention, only one extraction column may be used, or a plurality of extraction columns may be connected in series for extraction.
FIG. 2 is a schematic diagram of an embodiment of the present invention. In FIG. 2, extraction tower A10, extraction tower B11 and extraction tower C1
3 groups of 2 are connected in series. The extraction solvent sent from the extraction solvent tank 8 by the pump 9 sequentially passes through the three extraction towers to extract the active ingredient from the plant leaf and flow out. In this embodiment, the extraction tower filled with new swelling dry plant leaves is set to the extraction tower C located farthest from the extraction solvent tank, the extraction tower that has finished extraction at this position is placed in the extraction tower B, and the extraction tower is further extracted. It is preferable to place the extraction column that has finished extraction at position B in extraction column A that is closest to the extraction solvent tank. When the extraction is completed at the position of the extraction tower A, the plant leaves in the extraction tower are taken out and discarded. In the actual operation, the 4th extraction tower was used, and while the extraction was performed using the 3 extraction towers connected in series, the plant leaves that had been extracted from the 4th extraction tower were removed. It is possible to take out, fill with new swelling dry plant leaves, and switch the valve to successively change the relative positional relationship of the extraction tower. According to the method of the present invention, the active ingredient can be extracted more efficiently than the leaves of the swelling dry plant. The swellable dry plant leaf extract produced by the method of the present invention is of high quality because the extract does not come into contact with air and the active ingredient is not oxidized by oxygen in the air. The swellable dry plant leaf extract produced by the method of the present invention is used as it is, or diluted or concentrated, and further, depending on the purpose, the active ingredient is isolated as a solid by a method such as lyophilization and used. can do.

[0007]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Example 1 Using the apparatus shown in FIG. 2, black tea leaves were extracted with water at room temperature. The diameter of each of the three extraction towers is 208.3m.
m, the distance between the two strainers is 195 mm. In advance, put 100 g of tea leaves in 3 liters of water,
After standing for 6 hours, it was poured into a graduated cylinder equipped with a strainer at the bottom and drained to remove water, and the volume of swollen black tea leaves was 683 ml. First, using only the extraction tower A, the extraction tower A was filled with 2220 g of black tea leaves, and the flow rate was 5
Water was fed at 0 ml / min until 4.44 liters of the extract solution flowed out. Next, the extraction tower B filled with 2220 g of black tea leaves was connected to the extraction tower A, and water was sent through the extraction tower A and the extraction tower B at a flow rate of 50 ml / min until 4.44 liters of the extraction liquid flowed out. Furthermore, an extraction tower C filled with 2220 g of black tea leaves
Connected to the extraction tower B, and the extraction tower A, the extraction tower B and the extraction tower C
Water was flowed through at a flow rate of 50 ml / liter until 4.44 liters of the extract solution flowed out. When a part of the final extract was taken and evaporated to dryness, the heating residue in this extract was 1
It was 1.6% by weight. After the test was completed, the extraction tower was opened and the state of the black tea leaves inside was observed. As a result, the whole was uniform, and no evidence of uneven distribution of water and the extract was observed. Example 2 Black tea leaves were extracted with water at room temperature using the apparatus shown in FIG. All three extraction towers used in this example had a diameter of 98.3 mm and a distance of 4 between the two strainers.
It is 05 mm. The same black tea leaves as used in Example 1 were used, the amount of black tea leaves filled in each extraction tower was 740 g, the flow rate of water was 12.4 ml / min, and 1.48 liters of the extraction liquid was discharged at each time. The same operation as in Example 1 was repeated except that water was supplied. 1.48 liters of the final extract obtained by connecting Extraction Tower A, Extraction Tower B and Extraction Tower C were taken and evaporated to dryness.
It was 1.4% by weight. After the test was completed, the extraction tower was opened and the state of the black tea leaves inside was observed. As a result, the whole was uniform, and no evidence of uneven distribution of water and the extract was observed. Comparative Example 1 Using the same device and the same tea leaves as used in Example 2,
The same operation as in Example 2 was repeated, except that the amount of black tea leaves filled in each extraction tower was 450 g, and water was supplied until the extraction liquid 0.9 liters flowed out each time. The final extract obtained by connecting the extraction tower A, the extraction tower B and the extraction tower C to 0.9
When a part of the liter was taken and evaporated to dryness, the heating residue in this extract was 7.0% by weight, and the ratio of the extracted extract to black tea leaves was the same as in Example 2. However, the ratio of the extracted active ingredient was smaller than that in Example 2. After the test, the extraction tower was opened and the state of the black tea leaves inside was observed. As a result, in the extraction tower C, a part of the black tea leaves was not wet. Further, although the black tea leaves in the extraction tower B and the extraction tower A were all wet, the water and the extraction liquid were in a state of being thought to have drifted. From the results of Examples and Comparative Examples, in the extraction tower, when the swollen black tea leaves are in a compressed and densely packed state, uneven distribution of water and the extract does not occur, but the extraction is effectively performed. It can be seen that if the swollen black tea leaves are not densely packed in the extraction tower, the water and the extract liquid are unevenly distributed, and the black tea leaves that are not sufficiently extracted remain.

[0008]

EFFECTS OF THE INVENTION According to the method of the present invention, the extraction solvent does not drift in the extraction tower filled with swellable dry plant leaves,
Extraction is efficient and sufficient. Further, since the extract does not come into contact with air, there is no fear that the extracted active ingredient is oxidized by oxygen in the air, and high quality is maintained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an example of an extraction tower used in the method of the present invention.

FIG. 2 is a schematic diagram of one embodiment of the present invention.

[Explanation of symbols]

 1 Extraction Tower 2 Bottom Strainer 3 Extraction Solvent Inlet 4 Upper Strainer 5 Extraction Liquid Outlet 6 Air Venting 7 Jacket 8 Extraction Solvent Tank 9 Pump 10 Extraction Tower A 11 Extraction Tower B 12 Extraction Tower C

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yutaka Mizutani 2-3-3 Sengoku, Koto-ku, Tokyo Nagaoka Koryo Co., Ltd.

Claims (4)

[Claims] 1. A method for producing an extract by continuously extracting components in a swellable dry plant leaf packed in an extraction tower with an extraction solvent flow, wherein the swellable dry plant leaf is a swellable dry plant leaf. The apparent volume when swelled by the extraction solvent at normal pressure and extraction temperature is 1.2 of the volume of the packed part of the extraction tower.
A method for producing a swellable dry plant leaf extract, which is characterized in that the swellable dry plant leaf is packed in an extraction tower so that the swelled dry plant leaf is compressed, and extraction is performed in a compressed state. 2. The method for producing a swellable dry plant leaf extract according to claim 1, wherein the extraction tower has strainers on the inlet side and the outlet side of the extraction solvent flow in the packing section. 3. The ratio of the distance between the two strainers of the extraction tower and the diameter of the extraction tower is 0.5 / 1 to 4/1.
A method for producing the swellable dried plant leaf extract described. 4. The method for producing a swellable dry plant leaf extract according to claim 1, 2 or 3, wherein the swellable dry plant leaf is a tea leaf and the extraction solvent is water.