KR20230016429A - Method for Extracting Tannins from Persimmons Using Supercritical Fluid - Google Patents

Abstract

The present invention relates to a method for separating tannins from persimmons, and more particularly, to a method for separating tannins from persimmons, which includes a step of separating tannins from persimmons by adding a supercritical solvent and organic acid to persimmons. In addition, the present invention can separate tannins from persimmons by adding a supercritical solvent and an organic acid to persimmons and performing ultrasonic treatment instead of organic acids to separate tannins from persimmons. In addition, in the present invention, when separating tannin from persimmon by adding a supercritical solvent and organic acid to persimmon, tannin can be separated from persimmon by further performing ultrasonic treatment.

Description

Method for Extracting Tannins from Persimmons Using Supercritical Fluid {Method for Extracting Tannins from Persimmons Using Supercritical Fluid}

The present invention relates to a method for separating tannins from persimmons, and more particularly, to a method for separating tannins from persimmons by adding a supercritical solvent and an organic acid to the persimmons.

Persimmon flowers begin to bear fruit and become green immature persimmons 2 to 3 months later. At this time, some of the immature persimmons are thinned out to make the persimmon fruit more healthy and mature. Currently, most of the immature persimmons that have been thinned out are left unattended or used as compost to be used as food for birds or small animals.

Regardless of the variety, persimmon tannin exists as water-soluble tannin in immature fruits and gives off an astringent taste. As persimmon maturity increases and the sugar content of persimmon increases, the water-soluble tannin content gradually decreases, and in the case of sweet persimmons, they are removed while hanging on the branches.

Tannin is classified as a condensed tannin composed of catechins called Kaki tannin or shibuol. 1 schematically shows the structural formula of tannins.

Research on tannin components is weak, which is thought to be due to the diversity of tannin components. About 600 types of tannins have been reported so far, and recently, reports on tannins have continued.

Tannins have a very wide distribution in the plant kingdom, and are generally abundant in unripe fruits and seeds, and tend to decrease as they mature.

As reports that tannins, which have not been of much interest other than antidiarrheal action, are effective in ganglion action, skin protection action, and anticancer action, many studies are being attempted to find out what functional components are in tannins in addition to these characteristics.

Recently, tannins obtained from peony or moutan bark have been confirmed to have anti-allergic action or blood urea nitrogen level lowering action, and their main component has been found to be 1,2,3,4,6-penta-o-galloylglucose called gallotannin. Tannin prevents the peroxidation of lipids, and therefore, research is being conducted to develop tannin as an antioxidant additive for fats and oils.

In recent years, the amount of ultraviolet rays reaching the ground surface has increased along with the increase in ozone layer destruction, causing erythema, dryness, etc., and furthermore, skin cancer. Therefore, research is being attempted with much interest in the development of skin protectants using tannins.

On the other hand, tannins obtained from persimmons are known to have effects such as deodorization, gout prevention, skin beauty, and antibacterial effects.

(1) Deodorization

Bad breath and body odor are emerging as serious problems in interpersonal relationships for modern people living in closed spaces. These odors are related to daily diet, health status, age, gender, intestinal flora, etc. In particular, as the food consumed every day is digested, some of them change into substances that are harmful and have a strong odor. The main components are ingredients related to garlic and onions, such as methylmercaptan, hydrogen sulfide, and ammonia, and ingredients derived from high-protein, high-fat diets, such as indole, skatole, trimethylamine, hydrogen sulfide, amines, and ammonia.

There is also a hypothesis that these components are mainly produced in the large intestine, give stool a peculiar smell, and accelerate aging and cause disease when reabsorbed into the body. In addition, some of it is absorbed by the intestinal wall and discharged from the alveoli to the respiratory tract or released by the sweat glands, resulting in bad breath or body odor. In this case, general bad breath removal gum or oral spray products do not solve the problem.

Since persimmon tannins have the property of adsorbing these components in the large intestine and excreting them insoluble together with feces, it has already been found that they have the function of greatly reducing bad breath, off-odor and body odor, and condensed tannins play such a role in particular.

(2) Ventilation prevention effect

Persimmon leaf tannin is a polyphenolic compound composed of catechin, catechin-3-gallate, gallocatchin, and gallocatechin-3-gallate in a 1:1 ratio. :2:2 ratio, and other unknown compounds also exist. It is also known that these ingredients inhibit xanthine oxidase, which causes gout.

(3) Skin beautifying effect

Persimmon tannin forms a protective film while converging skin proteins, and it is known that this astringent action strongly suppresses the secretion of sebum.

(4) Antibacterial action

Persimmon tannin is far superior to green tea in its inhibitory effect on the growth of fungi, and is known to inhibit the proliferation of aspergillus, white hair mold, and black aspergillus in very small amounts.

On the other hand, the general method of extracting active ingredients from animals and plants is to use organic solvents such as water, methanol, ethanol, and hexane. The extraction method using an organic solvent is easy to apply, but it requires appropriate solvent selection, organic solvent remaining, difficulty in solvent removal, environmental pollution, low extraction yield, and a long extraction time of about 24 to 48 hours. It contains problems such as

The inventors of the present invention, while trying to obtain tannin, did not use expensive resources such as grapes or green tea, but instead used unripe persimmons or persimmon leaves, which are farmhouse by-products used as animal feed or compost, and supercritical solvents to obtain tannin content. It was found that this can be very high, and the present invention was completed.

An object of the present invention is to provide a method for separating tannin, a high value-added substance, from persimmon juice obtained from immature persimmons or persimmon leaves, which are agricultural by-products.

Tannins obtained from unripe persimmons or persimmon juice obtained from persimmon leaves of the present invention can be used as materials for pharmaceuticals, cosmetics, and health functional foods.

In the present invention, when tannins are separated from persimmons by adding a supercritical solvent and an organic acid to persimmons, tannins can be separated from persimmons by ultrasonic treatment instead of organic acids.

In the present invention, when tannins are separated from persimmons by adding a supercritical solvent and an organic acid to persimmons, tannins can be separated from persimmons by further performing ultrasonic treatment.

As described above, according to the present invention, tannins can be separated from persimmons in high yield by using a supercritical solvent and organic acid or supercritical solvent, organic acid and ultrasonic treatment from any one or more types of persimmons selected from immature persimmons and persimmon leaves. can

The present invention can obtain tannin from immature persimmons, one of farm by-products, so that the cost of producing tannin is reduced compared to conventional grapes, green tea, etc., and environmental problems can be solved by utilizing agricultural by-products. can also contribute to

Tannins obtained from persimmons according to the present invention can be applied to health functional foods, cosmetics, and pharmaceutical materials.

1 and 2 show a case in which the ultrasonic treatment step is performed and a case in which it is not performed.

In order to achieve the above object, the present invention represents a method for separating tannins from persimmons.

In the present invention, tannins can be separated from persimmons by applying any one or more methods selected from the following (1) to (3).

(1) A method for separating tannins from persimmons by adding a supercritical solvent and an organic acid to persimmons.

(2) A method of separating tannins from persimmons by adding a supercritical solvent to persimmons and treating them with ultrasonic waves.

(3) A method of separating tannins from persimmons by adding a supercritical solvent and an organic acid to persimmons to further perform ultrasonic treatment when separating tannins from persimmons.

Hereinafter, the method of separating tannins from persimmons of the present invention will be described in more detail.

(1) A method for separating tannins from persimmons by adding a supercritical solvent and an organic acid to persimmons

In the method (1), at least one selected from persimmons and persimmon leaves may be washed with water and crushed, and then a juice obtained by extracting the persimmon may be used.

In the method (1), at least one selected from persimmons and persimmon leaves may be washed with water and crushed, and then powdered persimmon powder may be used.

In the above, both aged and unripe persimmons can be used, but the tannin component is contained more in unripe fruits than in ripe fruits, and since mature persimmons are more valuable as a source of farm household income than unripe persimmons, conventional animals It is good to separate the tannin component from unripe persimmons used as feed or compost.

In the method (1), as the supercritical solvent, one or more selected from among ethanol, acetone, butanol, and ethyl acetate may be used, and ethanol may be preferably used. At this time, ethanol may be used, for example, 10 to 95% ethanol, more preferably 50% ethanol.

In the method (1), the supercritical solvent may be used in an amount of 1 to 10 times the weight of the decoction juice.

In the method (1), the supercritical solvent itself can extract tannin from persimmon, but it can increase the tannin content obtained by fermenting persimmon into acetic acid by acetic acid bacteria present in persimmon.

In the method (1), at least one selected from acetic acid, citric acid, ascorbic acid, malic acid, tartaric acid, and lactic acid may be used as the organic acid. The organic acid may be used in the same amount as the above-mentioned supercritical solvent, and in this case, 1 to 10% organic acid may be used.

In the method (1), the organic acid is used for the purpose of increasing the extraction efficiency of tannins rather than extracting tannins with a supercritical solvent alone by natural fermentation while preventing the growth of germs that may be contained in persimmons when tannic acid is obtained from persimmons. can

After separating the tannins from the persimmons, concentration may be performed on the tannin-containing solution in a solution state. At this time, the concentration of the tannin-containing solution can be carried out using a concentration method commonly performed in the food-related field. As an example of such a concentration method in the present invention, any one method selected from vacuum concentration, reduced pressure concentration, and atmospheric pressure concentration may be used. In the present invention, since such a concentration method can be selected and carried out by a person skilled in the art, the details thereof will be omitted.

In the present invention, the tannin-containing solution obtained from persimmon may be concentrated and used as a concentrate, the solvent may be removed to obtain only tannin obtained from persimmon, or tannin powder may be obtained from the tannin-containing solution by spray drying. .

(2) A method of separating tannins from persimmons by adding a supercritical solvent to persimmons and treating them with ultrasonic waves.

In the method (2) of the present invention, since the information on the supercritical solvent is mentioned in the method (1) above, the details thereof will be omitted.

Method (2) of the present invention is a method of separating tannins from persimmons by performing ultrasonic treatment in place of the organic acid in method (1).

When the tannin is separated from the persimmon by ultrasonication, the ultrasonic treatment may be performed to the extent that tannin can be separated from the persimmon. As an example of such ultrasonic treatment in the present invention, ultrasonic treatment may be performed at 20 to 48 kHz for 1 to 3 hours.

(3) A method of separating tannins from persimmons by adding a supercritical solvent and an organic acid to persimmons and further performing ultrasonic treatment when separating tannins from persimmons.

Method (3) of the present invention can be carried out by combining the methods (1) and (2) mentioned above.

In the (3) method of the present invention, the persimmon, supercritical solvent, and organic acid are mentioned in the above (1) method, and the ultrasonic treatment is mentioned in the above (2) method, so the details are omitted below. do it with

On the other hand, the present invention includes a health functional food containing tannins obtained from persimmons by the methods (1) to (3) above. At this time, tannins may be included in 0.1 to 1.0% by weight in the health functional food.

On the other hand, the present invention includes cosmetics containing tannins obtained from persimmons by the methods (1) to (3) above. At this time, tannins may be included in the cosmetics in an amount of 0.1 to 5.0% by weight.

On the other hand, the present invention includes a pharmaceutical product containing tannin obtained from persimmon by the methods (1) to (3) above. At this time, tannins may be included in 0.1 to 3.0% by weight in pharmaceuticals.

Hereinafter, the contents of the present invention will be specifically described through examples and test examples. However, these are for explaining the present invention in more detail, and the scope of the present invention is not limited thereto.

Immature persimmons with green skins were washed with water, foreign substances were removed, sliced into 2±0.5 cm in size, crushed, juiced, and filtered to obtain a juice solution.

12 kg of 20% ethanol was added to 6 kg of the persimmon juice, and after 12 weeks at 25 ° C, the content of soluble tannin from the persimmon juice was measured by the vanillin method, and the results are shown in the table below. 1.

<Example 1>

Immature persimmons with green skins were washed with water, foreign substances were removed, sliced into 2±0.5 cm in size, crushed, juiced, and filtered to obtain a juice solution.

12 kg of 10% ethanol and 12 kg of 3% acetic acid were added to 6 kg of the persimmon juice, and after fermentation at 25 ° C for 12 weeks, the content of water-soluble tannins from the persimmon juice was measured in the same manner as in Comparative Example. are shown in Table 1 below.

<Example 2>

Immature persimmons with green skins were washed with water, foreign substances were removed, sliced into 2±0.5 cm in size, crushed, juiced, and filtered to obtain a juice solution.

12 kg of 20% ethanol and 12 kg of 3% acetic acid were added to 6 kg of the persimmon juice, and after fermentation at 25 ° C for 12 weeks, the content of water-soluble tannins from the persimmon juice was measured in the same manner as in Comparative Example. are shown in Table 1 below.

item Water-soluble tannin content
(mg/L) Comparative Example 1 (20% ethanol) 80 Example 1 (10% ethanol+3% acetic acid) 120 Example 2 (20% ethanol+3% acetic acid) 189

<Example 3>

Immature persimmons with green skins were washed with water, foreign substances were removed, sliced into 2±0.5 cm in size, crushed, juiced, and filtered to obtain a juice solution.

After adding 4 kg of 50% ethanol to 1 kg of the above persimmon juice and ultrasonic treatment at 48 kHz for 2 hours, the content of water-soluble tannin obtained from the persimmon juice was measured in the same manner as in Comparative Example, and the results are shown in the table below. 2.

On the other hand, 4 kg of 50% ethanol was added to 1 kg of the above-mentioned persimmon juice, and after 12 weeks at 25 ° C., the content of water-soluble tannin obtained from the persimmon juice was measured in the same manner as in Comparative Example. Control 1 is shown in Table 2 below. was

<Example 4>

Immature persimmons with green skins were washed with water, foreign substances were removed, sliced into 2 ± 0.5 cm in size, crushed, and powdered with a grinder to obtain persimmon powder.

After adding 9 kg of 50% ethanol to 1 kg of the persimmon powder and ultrasonic treatment at 48 kHz for 2 hours, the water-soluble tannin content obtained from the persimmon powder was measured in the same manner as in Comparative Example, and the results are shown in Table 2 below. showed up

On the other hand, 9 kg of 50% ethanol was added to 1 kg of the persimmon powder, and after 12 weeks at 25 ° C, the content of water-soluble tannin obtained from the persimmon powder was measured in the same way as in Comparative Example. shown in

item water soluble tannins Example 3 240 (mg tannin/kg juice) Example 4 1450 (mg tannin/100g powder) control 1 98 (mg tannin/kg juice) control 2 340 (mg tannin/100g powder)

As shown in the results of Table 2, in the present invention, it can be seen that the tannin content of Examples 3 and 4 in which supercritical solvent and sonication were combined was significantly higher than the tannin content of Controls 1 and 2 obtained from persimmons using only the supercritical solvent. there is.

Immature persimmons with green persimmon skins were washed with water, foreign substances were removed, sliced into 2 ± 0.5 cm in size, crushed, juiced, and filtered to obtain a persimmon juice.

4 kg of 50% ethanol and 4 kg of 3% acetic acid were added to 1 kg of the above persimmon juice, and after 30 minutes, ultrasonication was performed at 48 kHz for 2 hours to obtain water-soluble tannin from the persimmon juice. At this time, the tannin molecular composition was measured using GPC (Gel Permeation Chromatography) for 30 minutes before sonication, and the tannin molecular composition obtained after sonication was measured using GPC, and the results are shown in FIGS. 1 and 2.

As shown in the chromatogram (GPC), tannins with high molecular weight are eluted early, and tannins with small molecular weight are eluted later. When comparing the sweetened juice before (Fig. 2a) and after (Fig. 2b) ultrasonic treatment, the amount of high-molecular tannins peaking at 8.5 minutes after sonication was significantly reduced, and the 10.5 peak had a small molecular size. It can be seen that it has moved towards In addition, a new peak was formed from 12.5 minutes to 13 minutes, indicating that the high molecular tannin was decomposed and the molecular weight was reduced to 11 to 13 minutes.

As described above, although it has been described with reference to the preferred embodiments of the present invention, those skilled in the art will variously modify and modify the present invention within the scope not departing from the spirit and scope of the present invention described in the claims below. You will understand that you can change

Claims (4)

A method for separating tannins from persimmons, characterized in that tannins are separated from persimmons by adding persimmons, supercritical solvents and organic acids. The method of claim 1, wherein the supercritical solvent is supercritical carbon dioxide, which has a critical temperature of 31.1°C and a critical pressure of 7.4 MPa. The method of claim 1, wherein the organic acid is at least one selected from acetic acid, citric acid, ascorbic acid, malic acid, tartaric acid, and lactic acid. The method for separating tannins from persimmons according to claim 1, wherein ultrasonic treatment is additionally performed when separating tannins from persimmons by adding a supercritical solvent and an organic acid.

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