JP3138332B2 - Production method of a new food material from oolong tea leaves - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Industrial application fields] There are many types of teas made from tea leaves, such as black tea, oolong tea, green tea, Pu'er tea, extended tea, Japanese tea, Chinese tea, Indian tea, etc., depending on the processing method and production area of tea leaves. Divided into In addition, tea leaves include vitamins, minerals, tannins, caffeine, saponins,
There are many components such as catechins, flavonoids, chlorophyll, etc.
It is also known to be effective in deodorization, suppression of blood pressure increase, suppression of increase in blood cholesterol and lipid, suppression of weight increase, prevention of tooth decay, and the like.

[0002] The inventor of the present invention extracts various tea leaves,
When studying the separation, purification and utilization, for example, as shown in Test Example 1, it was found that only the extract of oolong tea exhibited a specific surface activity, and for example, as shown in Example 1, The present inventors have also found that this property is found in a fraction containing a large amount of dimeric or trimeric catechin when subjected to fractionation, and thus completed the present invention.

[0003] That is, the present invention relates to a novel method for producing a food material utilizing the properties of a fraction containing catechin dimers and trimers of oolong tea leaves among many types of tea leaves, It is used when producing ingredients that give food a refreshing flavor.

[0004]

2. Description of the Related Art An adsorbent is added to an extract obtained by extracting tea leaves such as green tea, oolong tea, and black tea with a hydrophilic organic solvent such as a lower alcohol or an aqueous solution thereof or water (hot water or hot water) to perform an adsorption treatment. A method of separating catechins adsorbed on an adsorbent with an extraction solvent has been known (for example, Japanese Patent Laid-Open No.
-31474, JP-A-3-14527, etc.). There is also known a method of using an extract extracted from tea leaves to moisten a wet tissue (JP-A-3-29623).

[0005]

These known methods do not use the properties of oolong tea leaves that are unique to them, but utilize the properties of tea leaves in general. It is. Therefore, teas including green tea and black tea as well as oolong tea are widely used as raw materials.

In the method of extracting and separating catechins by a known method, since water or a hydrophilic organic solvent or an aqueous solution thereof is used for the extraction, the surfactant effect of dimer or trimer of catechin is used. The extraction of the component having was not sufficient.

[0007] In the method of using a tea leaf extract to wet a wet tissue, a surfactant such as sucrose fatty acid ester or polyglycerin ester for producing a surfactant effect is added. Therefore, in this method, it is appropriate to consider that the extract of tea leaves is used for obtaining other effects such as deodorization, rather than being used for the purpose of surface activity. It has not been known that the liquid has a surface active effect.

According to the findings obtained by the inventor of the present invention, for example, as shown in Test Example 2, the component having surface activity is more similar to a citric acid solution than when oolong tea leaves are extracted with water (hot water). Extraction was easier when extracted with an acidic solution. Therefore, when the extraction was performed using the acidic solution, a component exhibiting surface activity could be extracted not only from the tea leaves before oolong tea was extracted, but also from the tea leaves as the extracted residue after the oolong tea was once extracted.

Furthermore, as shown in the test examples, the component exhibiting this surface activity was found only in the tea leaves of oolong tea, but was not found in tea leaves such as green tea and black tea. The present invention utilizes, as a food material, a fraction containing a large amount of dimeric or trimeric catechin having a surface active effect, which is possessed only by the extract of oolong tea.

[0010]

SUMMARY OF THE INVENTION The present invention relates to an oolong tea leaf having an acid content of an acid concentration corresponding to an acidity of 0.1 to 2.0% in terms of citric acid with respect to 100 parts by weight of its dry weight. More than 500 parts of the liquid is added and subjected to extraction treatment, and the obtained extract is subjected to fractionation treatment using an adsorbent or a separation membrane, and caffeine,
The present invention relates to a method for producing a food material using oolong tea as a raw material, in which a fraction containing a large amount of theobromine and the like is removed, and a fraction containing a large amount of catechin dimers and trimers and having a surfactant effect is collected. .

[0011] The oolong tea used herein refers to a half-fermented tea leaf, and can be used those generally called Chinese tea, Tian Guan Yin, Oolong tea and the like. Moreover, you may use the tea leaves which are the extraction lees after extracting such tea leaves once with boiling water.

The extraction treatment is performed by adding an acid solution to oolong tea leaves. The acidic liquid used here is citric acid in water,
Lactic acid, acetic acid, hydrochloric acid, refers to an acidic liquid such as an aqueous solution containing a large amount of acid such as ume vinegar, lemon juice, and so on, and the amount of acid converted to citric acid is 0.1 to 2.2.
Acidity equivalent to 0% can be used. If the amount of acid is lower than this, the extraction of catechin dimer and trimer will be worse,
If the acidity is high, the polymerization of catechins proceeds to produce a polypolymer, which has an adverse effect such as strong coloring.

The extraction process is performed at a temperature of 60 ° C. or more, preferably 80 ° C.
It is better to carry out at a temperature of at least ℃. That is, the heated acid solution is added to the tea leaves of oolong tea, or the acid solution is added to the tea leaves of oolong tea and heated to a temperature of 60 ° C. or higher, and the temperature is maintained and the extraction is performed. The extraction time varies depending on the condition of the oolong tea to be used, the extraction method, the structure of the extraction device, the amount of acid in the acidic solution, and the like. Therefore, it is desirable to extract the extract as densely as possible while observing the condition. The acidic liquid is
It is desirable to use 500 parts or more of the oolong tea leaves in an amount of 100 parts in terms of dry weight.

The extracted oolong tea leaf extract is subjected to a fractionation treatment using an adsorbent and / or a separation membrane to remove a fraction containing a large amount of caffeine, theobromine, etc., and to convert catechin dimer or trimer. A fraction containing a large amount and showing a surfactant effect is collected. In this case, silica gel, cellulose beads, modified cellulose beads, styrene polymer beads, polyvinyl alcohol beads and the like having an adsorptivity can be used as an adsorbent, and a cellulose membrane as a separation membrane can be used.
A membrane such as an ion exchange resin membrane and a ceramic membrane is used.

The treatment with the adsorbent is carried out by filling the column with the adsorbent, flowing the extract to adsorb the extracted components, and then flowing the eluate through the column to elute the adsorbed components. I do. As the eluate, water and an aqueous solution of a water-soluble organic solvent are used. As the water-soluble organic solvent, lower alcohols, acetone, ketones and the like can be used.

When the components adsorbed on the adsorbent are eluted with the eluate, amino acids, caffeine,
Components related to taste such as bitterness and umami such as theobromine and polysaccharide are eluted, but this part hardly contains catechin. In the middle part after the part containing many components related to this taste is eluted, two of catechin,
A portion containing a large amount of trimers and a component showing surface activity is eluted. Further, a solution containing a large amount of monomeric catechins such as epicatechin, epigallocatechin gallate, and epicatechin gallate elutes in the latter part. It is desirable that the concentration of the organic solvent in the eluate is gradually increased as necessary as the elution progresses, so that components that have not been eluted until then are easily eluted.

[0017] In this manner, a portion containing a large amount of caffeine or theobromine and a lot of components related to taste is removed, a portion containing a component exhibiting surface activity is separated, and if necessary, concentrated and / or dried to obtain oolong tea. As a new food material. A portion containing a large amount of components related to taste at the beginning or a portion containing a large amount of a catechin monomer later can be used as a food material or the like.

The treatment with the separation membrane can be carried out by any known method. For example, an oolong tea extract is passed through one side of the separation membrane and permeated through the separation membrane, as in the circulation type Diaris method. This is performed by causing the permeated liquid to flow out from the other surface. By using a membrane having an appropriate property, a permeate containing a large amount of catechin dimers or trimers and having a strong surface activity can be permeated. At this time, if necessary, the film portion is heated or, if necessary, treated by adding a water-soluble organic solvent. By treating in this manner, a fraction containing a large amount of catechin dimers and trimers is obtained. In order to speed up the process, the extract may be supplied in a pressurized state.

By treating in this manner, a solution containing a large amount of catechin dimers and trimers and having a high surface activity is used as it is, or, if necessary, concentrated or dried to obtain a food material.
Concentration and drying are desirably performed at a reduced pressure or in a frozen state at a temperature as deep as possible so that polymerization of catechin does not occur during that time.

This novel food material made from oolong tea contains a large amount of catechin dimers and trimers,
It shows antioxidant properties and has the effect of refreshing the aftertaste of food when used as a food material.

[0021]

【Example】

Example 1 To produce oolong tea as a canned beverage, 5 liters of a 1.0% citric acid solution was added to 1 kg of tea leaves, which are extracted lees of oolong tea after extraction, and the mixture was boiled for 15 minutes to perform an extraction treatment. And filtered to give 4.5 l of extract. The extract was concentrated under reduced pressure until the volume became 1 l, and then allowed to cool at room temperature for 12 hours. Then, the cooled concentrated extract was added to 4.0,
The precipitate was separated by centrifugation at 00 rpm for 10 minutes to obtain an extract for fractionation.

One liter of the extract for fractionation was introduced at a flow rate of 28 ml / min into a column previously filled with water and Sephadex (Sephadex LH-20) to adsorb the extracted components. When the extract has been flowed in, 3,000 ml of water and then 3,000 ml of 15
A 30% acetone solution was further eluted with a 30% acetone solution, and finally a 2,500 ml 60% acetone solution was eluted with increasing acetone concentration in the eluate.
The eluate eluted from the column was obtained by removing the first 380 ml of eluate corresponding to the amount of water that had entered the column from the beginning, and then sequentially collecting eluates in the amounts shown in Table 1.
The eluates of fractions Nos. 3 to 6 were separately concentrated under reduced pressure and freeze-dried to obtain novel food materials using oolong tea leaves corresponding to the respective fractions as powders.

The food material thus obtained was added in 0.1% each to mints chewing gum, black tea candy and yogurt, compared to the non-added food materials.
The refreshing and refreshing flavor became strong.

Table 1 shows the results of measuring the amounts of caffeine, theobromine, and catechin in the freeze-dried powders of these food materials and other fractionated solutions, and the surface activity of a 1% solution thereof. Was. In addition, the amount of catechin was measured by a high performance liquid chromatographic method, determined by a value converted to the amount of epicatechin, and the surface activity was measured by the method described in Test Examples.

[0025]

Incidentally, the dimers and trimers in the table are catechin dimers,
It is a trimer, and a multimer is a polymer in which catechin is further polymerized.

As shown in Table 1, when eluted with the eluate, caffeine and theobromine eluted first, followed by an eluate containing a large amount of catechin dimers and trimers and having a large surface activity. After that, when the elution was further continued, the amount of catechin dimer and trimer was reduced, and an eluate containing a large amount of catechin monomer was eluted. Therefore, by taking out fractions No. 3 to No. 6 and concentrating or / and pulverizing, a food material having a strong surface activity and giving a refreshing flavor when added to food can be obtained.

EXAMPLE 2 5 l of a 1.2% citric acid solution at 95 ° C. was added to 500 g of oolong tea leaves and heated to 95 ° C. to bring the temperature to 10 ° C.
The mixture was allowed to stand for 5 minutes to extract, and then filtered through a nylon cloth to obtain 3.5 l of an extract. This extract was concentrated in the same manner as in Example 1 to obtain an extract for fractionation.

[0029] One liter of this fractionation extract was applied to Sephadex.
Using a (Sephadex LH-20) column, the same treatment as in Example 1 was performed to fractionate. The solutions of fractions Nos. 3 to 6 were combined, concentrated under reduced pressure, and freeze-dried to obtain a novel food material using powdered oolong tea leaves as a raw material. The addition of 0.1% of this food material to orange juice resulted in a refreshing and refreshing beverage.

Example 3 1 l of the extract for fractionation described in Example 1 was circulated using a membrane separator (Carbosep Micro Module Micro 40) equipped with a Carbosep membrane (M-20, manufactured by Sumitomo Heavy Industries). It was processed by the Dialis method. The extract for fractionation put in the storage tank is used as a stock solution in the membrane separation device for 40 minutes.
The flow was at a flow rate of ml / min. The stock solution once passed through the membrane separation device was returned to the storage tank by a pump, circulated between the storage tank and the membrane separation device, and a membrane separation process was repeatedly performed. On the other hand, the permeate separated by the membrane separation device is
Collected in the permeate tank. The permeate separated after the treatment for 3 hours was freeze-dried to obtain a novel food material made from powdered oolong tea leaves.

The lemon candy to which 0.1% of this powdered food material was added became refreshing after eating. In addition, the one with 0.1% added to the lemon beverage had a stronger refreshing feeling after drinking. Table 2 shows the results obtained by measuring the catechin content and the surface activity of a 1% solution of the lyophilized powder of the food material and the stock solution remaining in the storage tank after the treatment.
It became like.

[0032]

The control in the table is based on the result of measuring the surface activity of water (pure water). As shown in Table 2, the food material obtained here contained many catechin dimers and trimers, and strong surface activity was observed. The result is a refreshing aftertaste when eaten in addition to food.

Test Example The measurement of the surface activity described in this specification was performed by the following method. In addition, each method calculated | required the value which averaged the result of having measured each five times. Muslin method A solution containing the surfactant to be measured
Put a predetermined amount of oil and fat evenly in a muslin cloth cut into a 2 cm diameter disc on the surface, gently place it in a graduated cylinder of ml capacity, settle down and reach the bottom of the graduated cylinder Is obtained in seconds. The greater the surface activity, the faster the muslin cloth impregnated with oil and fat is wetted, and the easier it is to settle, and the shorter the measurement time.

Surface tension The surface tension was measured using a surface tension meter manufactured by Junoi. That is, the solution containing the surfactant to be measured is placed in a small petri dish, a ring made of platinum wire having a diameter of 1.2 cm is hung on the tip of the screw screw, and the surface of the solution is brought into contact with the solution surface. Gently pulling down, the tension when the ring separates from the liquid surface is calculated in dynes / cm. The larger the surface activity, the more easily the ring is separated from the liquid surface, and thus the smaller the measured value.

Test Example 1 500 g of green tea, black tea and oolong tea leaves were prepared, and 5 l of each of them was added with hot water containing 0.5% citric acid, and the mixture was extracted at 95 ° C. An extract of tea leaves was obtained. Next, each extract was concentrated under reduced pressure and then freeze-dried to obtain a powder. A 1% solution thereof was prepared, and the surface activity was measured by the muslin method and a surface tensiometer.

[0037] Both the muslin method and the surface tension showed that oolong tea had a higher surface activity than green tea or black tea, and that the surface activity was a property specific to oolong tea.

Test Example 2 Hot water, 0.5% citric acid solution and 1.0% citric acid solution were added to 500 g of separately prepared oolong tea leaves in an amount of 5 l each, followed by extraction treatment to extract each oolong tea extract. I got Next, each extract was freeze-dried to obtain powdered tea, a 1% solution thereof was prepared, and the degree of coloration and the amount of catechin monomer and catechin di- and trimer were measured. Was. The degree of coloring was measured at an absorbance of 400 nm. The amount of catechin was determined in the same manner as in Example 1.

[0039] The smaller the amount of citric acid, the greater the absorbance and the greater the color. In addition, the amount of catechin monomers, dimers and trimers was reduced. This is presumed to be because the higher the pH, the more the catechins are polymerized during the extraction treatment, and the higher the pH, the more the colored substances become more polymerized than the dimer or trimer.

Claims (1)

(57) [Claims] 1. Oolong tea leaves having a dry weight of 10
The amount of acid converted to citric acid is 0.1 to 2.0% with respect to 0 parts.
Of the resulting extract is subjected to a fractionation treatment using an adsorbent or a separation membrane to remove a fraction containing a large amount of caffeine, theobromine and the like. A method for producing a novel food material using oolong tea leaves as a raw material, characterized in that a fraction containing a large amount of monomer and having a surfactant effect is collected, and if necessary, concentrated and dried.