JP4278566B2 - Fermented tea production method - Google Patents

Description

  The present invention relates to a method for producing fermented tea obtained by fermenting tea leaves using microorganisms in the presence of tea stems.

As the dietary habits of Japan become richer, the number of adults with symptoms of hyperlipidemia has increased, and as a result, it has become a problem inducing diseases such as obesity, arteriosclerosis, and thrombosis. As a prophylactic and therapeutic agent for hyperlipidemia, the cholesterol lowering action contained in various foods has attracted attention, and the functionality of teas, one of which has attracted attention. For example, the lipid metabolism action (for example, refer nonpatent literature 1) of puer tea which is a kind of black tea of Chinese tea, and the cholesterol temporary reduction effect | action (for example, nonpatent literature 2) of various black tea are reported. In addition, there is known a substance for suppressing an increase in blood sugar level comprising an extract of black tea having such an action (see, for example, Patent Document 1).
Sano et al., 1986 Chem. Pharm. Bull (Tokyo) 34, 1, p221-8 Yang et al., Pharmacological Research, Vol. 35, No. 6, 1997: 505-512 JP 2002-370994 A

  However, according to the inventor's knowledge, it has been found that it usually takes about 40 days or more to produce black tea as a raw material of the disclosed technology, and physiological activities such as cholesterol-lowering action of black tea. Thus, there is a demand for a method that can produce black tea in a short period of time while maintaining the above, and that improves the yield of the extract from fermented tea.

  Therefore, as a result of intensive research in view of such circumstances, the present inventor, as a result of fermenting tea leaves in the coexistence of tea stems, in a method for producing fermented tea, while maintaining physiological activities such as cholesterol lowering activity The inventors have found that the yield can be improved in a short time and have completed the present invention.

  According to the production method of the present invention, the production time of fermented tea can be shortened and the yield of the extract from the fermented tea can be improved while maintaining physiological activities such as cholesterol lowering action.

  In the present invention, tea leaves obtained from tea plants such as Chinese large leaf species, Chinese small leaf species, Shan species, Assam species and the like can be used.

  In the present invention, it is preferable to perform heat treatment for the purpose of preventing oxidation or the like by enzymes contained in the tea leaves before performing the fermentation treatment, and such heat treatment eliminates the green odor of tea leaves and obtains a good fragrance. It becomes possible. In this heat treatment, tea leaves obtained by heat-treating the harvested tea leaves may be used as they are, but tea leaves that have been self-digested with enzymes contained in the tea leaves before the heat treatment and processed into semi-fermented oolong tea or post-fermented black tea May be used as a raw material. Heating methods include heating the tea leaves using a direct-fire method using a kettle, various dryers that use electricity as the heat source, a method using a steaming heating dryer that uses steam, and sun drying exposed to sunlight. Any method can be used as long as the enzyme can be inactivated. The heating conditions at this time may be heating at a high temperature of 20 ° C. or higher, preferably 100 to 200 ° C. for 10 seconds or longer, preferably 30 to 3,000 seconds.

In the present invention, in fermenting the tea leaves as described above, the greatest feature is to coexist with tea stems, which will be described below.
The tea leaves and tea stems used for fermentation are not particularly limited in size. You may use as it is, and you may use what was cut with the crusher, the grinder, the mill, the ball mill, etc.

  The cooling after heating is not particularly limited, but may be performed by cooling with a ventilator, cooling with a cooler, or the like in the fermentation chamber, or may wait for natural cooling.

  Further, the tea leaves and tea stems to be subjected to fermentation are humidified by spraying or the like, and the water content is 30% by weight or more, further 30 to 50% by weight, the water content after fermentation is 20% by weight or less, It is preferable to be 10 to 19% by weight, and if the water content before fermentation is less than 30%, the fermentation may not proceed sufficiently, and if the water content after fermentation exceeds 20%, the cause of spoilage Therefore, each is not preferable.

  In the fermentation using the tea leaves and tea stems treated as described above, the coexistence amount of tea stems is not particularly limited, but 25 parts by weight or more of tea stems may coexist with 100 parts by weight of tea leaves. Preferably, more preferably 25 to 60 parts by weight, particularly preferably 27 to 40 parts by weight, and if the coexistence amount is less than 25 parts by weight, aeration during fermentation deteriorates, the fermentation state does not become constant, This is not preferable because the amount of active ingredient produced decreases. On the other hand, if it is 60 parts by weight or more, the active ingredient of tea leaves cannot be fermented, and the amount of active ingredient is reduced.

  Moreover, in fermentation, in order to fully obtain the flavor and physiological activity peculiar to fermented tea, it is preferable to ferment in the presence of microorganisms (mold). The fungi used may be naturally occurring, but Aspergillus awamori, Aspergillus saitoi, Aspergillus niger, Aspergillus oryzae and other genus Aspergillus or Rhizopus demer (R ) And other molds for food processing such as Tempe fungus can be used, and Aspergillus genus and Rhizopus genus are preferable in terms of expression of physiological activity. Although the kind of mold to be used may be one kind or a mixture of plural kinds, pure fermentation using one kind of mold is preferable.

  In order to inoculate the above mold, powder mixing the tea leaves and tea stems and mold spores as they are, or powder mold spores once mixed with a food excipient such as wheat flour, rice flour, barley flour, etc. Examples thereof include a method in which tea leaves and tea stems are mixed after the spores are diluted once, and a method in which mold spores are suspended in physiological saline and sprayed on tea leaves and tea stems. The amount of mold inoculated is preferably 0.001 to 1% by weight, more preferably 0.01 to 0.5% by weight, based on the total amount of tea leaves and tea stems. If the amount of inoculated is less than 0.001% by weight, it may not be able to be sufficiently fermented.

  Any of these strains may be purchased as a mold for inoculating molds such as sake sake koji, mirin koji, shochu koji, tempeh koji, etc. It can be left and reused as seed seeds and can be obtained without any restrictions.

Next, the inoculated tea leaves and tea stems are spread on a bed in the fermentation chamber and fermented. As for the temperature at the time of fermentation, it is preferable to raise the temperature of a fermented product to 32 degreeC or more within 25 hours after fermentation start, More preferably, it is 32-45 degreeC, Most preferably, it is 35-42 degreeC. And it is preferable to hold | maintain this temperature for at least 5 hours or more, More preferably, it is 5 to 10 hours. When deviating from such conditions, that is, when the temperature is not increased in a short time, the fermentation may not proceed sufficiently, which is not preferable.
By the above-mentioned method, it becomes possible to ferment in a short period of time, so that the fermentation can be carried out in 20 hours to 15 days, and further about 10 hours to 7 days.

  Thus, fermented tea is produced, but the content of caffeine in the fermented tea obtained by the method of the present invention is preferably 5% by weight or less, more preferably 3 to 5% by weight. When the caffeine content exceeds 5% by weight, the caffeine content in the extract is increased, and physiological actions such as excitatory action and diuretic action are increased, which is not preferable.

  The fermented tea produced as described above has physiological activity such as cholesterol lowering action, and when extracting such an active ingredient, it can be extracted with water or hot water.

  As such a method, fermented tea leaves can be put into an extraction tank and extracted by adding water or hot water, and the resulting extract is treated with a filter press after the solid-liquid separation by centrifugation, etc. The extract may be obtained by concentrating the extract, and the extract may be concentrated or further used in the form of drying. Such concentration methods include, but are not limited to, vacuum concentration, membrane concentration, freeze concentration and the like. Yes, for drying, it can be pulverized using spray-drying, freeze-drying, kneader, nauter mixer, etc., concentrated or dried, as a liquid or powdered extract, as it is, or other food It is used as a functional food by adding to the above.

Examples of foods specifically targeted when such extracts are used by adding to other foods include, but are not limited to, the following.
(1) Agricultural and hydro-acid processed products Harusame, Koshian, Konnyaku, Bread, Noodles (immediate noodles, pasta, raw noodles, dried noodles), rice cakes, cereal foods, processed soybean products (tofu, soy milk, natto, frozen tofu), hydroxylated Products [Kneaded products, (crab flavored) crab, (fish meat) ham, (fish meat sausage), (fish meat) winner, sprinkles, tea paste], egg-containing foods (soup, salmon, etc.), canned (oil sardine, Yakitori), retort food (curry, stew, spaghetti)
(2) Dairy products Milk, processed milk, lactic acid bacteria beverages, butter, cheese, condensed milk, powdered milk (3) Confectionery Cake, mousse, (powder) dessert, ice cream, rice cake, chocolate, gummi, candy, cookies, wafers, jelly (4) Seasoning Miso, soy sauce, umami (flavor) seasoning, (powder) natural seasoning, sauce, dressing, grilled meat sauce, mirin, curry, stew, spices, spices, yogurt (5) Beverages Soft drinks ( Carbonated drinks, fruit drinks, sports drinks, nutritional drinks), taste drinks (coffee, cocoa, wort)

(6) Health food (dietary supplement)
<1> Saponin-containing foods (Ginseng root-containing foods, Ezokogi-containing foods)
<2> Sugar-containing foods Sugar-containing foods [oligosaccharides (fructo-oligosaccharide-containing foods, isomalt-oligosaccharide-containing foods, galactooligosaccharide-containing foods), polysaccharides (shiitake-containing foods, mucopolysaccharides, protein-containing foods, chondroitin sulfate-containing foods, (Food containing Mannentake) (food containing chitin, chitosan)
<3> Mineral-containing foods (calcium-containing foods, alfalfa-containing foods, prune extract foods, β-carotene-containing foods)
<4> Oil and fat-containing food
Fats and oils containing vitamin E [wheat (wheat, pigeon) germ oil, soybean germ oil, rice germ oil] food containing eicosapentanoic acid, food containing soybean lecithin, food containing γ-linolenic acid (primrose oil, borage oil), docosahexaenoic acid Contained food <5> Protein-containing food
Soy protein-containing food, casein, whey protein, koji processed food <6> Taurine
Oyster processed food, Shijimi processed food (7) Others <1> Suppon processed food, food for abnormal amino acid metabolism, liquid food (disease food)

Hereinafter, the present invention will be specifically described with reference to examples.
In the examples, “parts” and “%” are based on weight unless otherwise specified.

Example 1
Chinese tea leaves and tea stems were harvested, 100 parts of tea leaves and 37 parts of tea stems were placed in an open fire kettle and roasted in a roasting kettle for 25 minutes at 90 ° C. After standing to cool, spray water with a spray bottle to bring the water content to 32%, and then put it in the fermentation chamber and add 0.1% of Aspergillus fungus to the total amount of tea leaves and tea stems. After thoroughly mixing and raising the temperature in the system to 37 ° C. in 25 hours, fermentation was continued at that temperature for 80 hours. The amount of caffeine contained in the fermented tea obtained as described above was 4.8% by weight.
Production time of fermented tea by the above production method, yield of extract and physiological activity were evaluated according to the following criteria.

(Manufacturing time)
After the start of fermentation, the temperature and humidity of the tea leaves were measured, and the state and physiological activity of the tea leaves after 80 hours were evaluated.

(Production yield)
198 g of the fermented tea leaves obtained above were put into an extraction tank, 1000 mL of water was added, and the mixture was extracted at 120 ° C. for 1 hour to obtain 1150 mL of an extract. After centrifuging this extract, foreign matters were removed by a filter press, and the yield of the extract obtained by freeze-drying was examined after concentrating the obtained extract.
In calculating the yield (%), dry powder weight / fermented tea leaf × 100 (%) was used.

(Physiological activity)
Eleven volunteers with hypercholesterolemia (average total cholesterol level: 231 mg / dL) were subjected to an informed consent original test as follows.
The day before the test, from 20:00, fasting and fasting were conducted, and a single oral administration test was conducted after consulting with a doctor. As a control, 30 g of butter was ingested, blood was collected 6 hours after ingestion, and the amount of cholesterol was measured. In the test, 1 to 5 g of this dried product was taken simultaneously with butter, blood was collected after 6 hours, the amount of cholesterol was measured, and the inhibition rate (%) from the cholesterol level of the control was evaluated.

Example 2
In Example 1, fermented tea was similarly obtained and evaluated in the same manner except that the tea stem content was changed to 55 parts. The caffeine content contained in the fermented tea obtained as described above was 4.3%.

Example 3
In Example 1, fermented tea was similarly obtained and evaluated in the same manner except that the tea stem content was changed to 30 parts. In addition, the caffeine content contained in the fermented tea obtained above was 4.7%.

Example 4
In Example 1, fermented tea was similarly obtained and evaluated in the same manner except that the mold type was changed to the genus Rhizopus. The caffeine content contained in the fermented tea obtained as described above was 4.5%.

Example 5
In Example 1, fermented tea was similarly obtained and evaluated in the same manner except that the coexistence amount of mold was changed to 1.0% with respect to the total amount of tea leaves and tea stems. The caffeine content contained in the fermented tea obtained as described above was 4.5%.

Example 6
In Example 1, except that it changed to the temperature of 45 degreeC at the time of fermentation, fermented tea was obtained similarly and evaluated similarly. The caffeine content contained in the fermented tea obtained as described above was 4.5%.

Comparative Example 1
In Example 1, except that the content of the tea stem was changed to 2 parts, similarly fermented tea was obtained and evaluated in the same manner. In addition, the caffeine content contained in the fermented tea obtained above was 5.1%.

  The evaluation results of Examples 1 to 6 and Comparative Example 1 are shown in Table 1.

[Table 1]
Extract yield (%) Production time (h) Bioactivity (%)
Example 1 30% 80h 50%
Example 2 27% 76h 45%
Example 3 33% 85h 53%
Example 4 30% 82h 51%
Example 5 29% 76h 50%
Example 6 31% 86h 50%
Comparative Example 1 20% 130h 15%

  The method for producing fermented tea of the present invention can shorten the production time and improve the production yield while retaining the physiological activities such as cholesterol lowering action of black tea.

Claims (5)

A method for producing fermented tea, characterized in that 25 to 60 parts by weight of tea stems coexist with 100 parts by weight of tea leaves and fermented at 32 to 45 ° C for 5 hours or more . 2. The method for producing fermented tea according to claim 1, wherein fermentation is performed in the presence of microorganisms. The method for producing fermented tea according to claim 2, wherein the microorganism is of the genus Aspergillus or the genus Rhizopus. The method for producing fermented tea according to claim 2 or 3, wherein the coexistence amount of microorganisms is 0.001 to 1% by weight based on the total amount of tea leaves and tea stems. The method for producing fermented tea according to any one of claims 1 to 4, wherein the content of caffeine in the obtained fermented tea is 5% by weight or less.