JP2014023472A - Method for producing powder tea - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing powder tea capable of providing the powder tea with sufficiently reduced bitterness and astringency and with refreshing, plain and palatable without worrying about the viscosity feeling, and contributing to health promotion, and whose main ingredient is green tea.SOLUTION: About 100 g of Tencha tea produced from a tea garden, which includes only mesophyll by using shaded tea leaves cultured under cover as raw material and removing veins and stems after drying the tea leaves without rolling, is roasted for 10 minutes at the temperature of about 110°C with an earthenware parching pan and a trivet under an atmosphere of 20°C and 45% of RH. Subsequently, the powder tea is obtained by finely pulverizing the Tencha tea after roasted into powder of about 5 μm particle diameter under the atmosphere of 20°C and 45% of RH, or by roasting about 100 g of a powder green tea by the same method.

Description

  The present invention relates to a method for producing powdered tea mainly composed of green tea.

  Tea with green tea powder (hereinafter referred to as powdered tea) dispersed in warm water or water can be used for drinking more easily than tea that uses a teapot to pour warm water into tea leaves and drink an extract. Moreover, since no tea husks are generated, it can contribute to the reduction of waste. Also, especially high-quality powdered tea is expensive and cannot be easily consumed. In addition, tea in which powdered tea is dispersed in warm water or water is an active ingredient such as n-3 polyunsaturated fatty acids, dietary fiber, catechins and flavonoids that can be ingested only partially by tea leaf extract. It is also possible to ingest the whole. However, powdered teas that are simply powdered from ordinary (tea leaves containing leafy meat, veins, stems, etc.), bancha, roasted tea, etc. are suitable for drinking because of their strong bitterness and astringency. Is hard to say. Therefore, as disclosed in Patent Document 1, a method of reducing the bitterness and astringency of powdered tea by roasting tea leaves of sencha at a low temperature of about 60 ° C. has been proposed.

JP-A-01-269451

  According to the method for producing powdered tea according to Patent Document 1 described above, the bitterness and astringency of powdered tea are reduced to some extent. However, the method for producing powdered tea according to Patent Document 1 requires a very long time for roasting, and thus is difficult to use for industrial production. In addition, although the method for producing powdered tea according to Patent Document 1 can reduce the bitterness and astringency of powdered tea to some extent, it has not always been effective.

  The object of the present invention is to solve the problems of the above-mentioned conventional methods for producing powdered tea, the bitterness and astringency are sufficiently reduced, and there is little thickness, it is clean and light, and it is delicious and easy to drink. It is an object of the present invention to provide a method for producing powdered tea capable of providing powdered tea mainly composed of green tea that can be ingested with components that cannot be consumed with green tea that drinks this extract and can contribute to health promotion.

  Among the present inventions, the invention described in claim 1 is a method for producing a powdered tea that can be consumed by being dispersed in hot water. The tea is roasted and finely pulverized (so that the particle size is about 100 μm or less). And a step of roasting matcha tea.

  The invention described in claim 2 is characterized in that, in the invention described in claim 1, the roasting temperature is 100 ° C. or higher and 180 ° C. or lower.

  The invention described in claim 3 is the invention described in claim 1 or claim 2, wherein the content of total free amino acids in the tea or green tea before roasting is 2.5% or more and 6.2%. The tannin content is 7.0% or more and 13.0% or less.

The invention described in claim 4 is the invention described in any one of claims 1 to 3, characterized in that roasting satisfies the following requirements (1) to (3). is there.
(1) Reduce the content of tannin in roasted tea or matcha before roasting by 40% or more (2) Reduce content of caffeine in roasted tea or matcha before roasting by 40% or more (3) Do not decrease the content of theanine in roasted tea or matcha before roasting by more than 70%

  According to the method for producing powdered tea according to the present invention, it is possible to enhance the taste and aroma, and reduce bitterness and astringency and change to a clean taste even for inexpensive, low-grade and low-grade tea leaves. As a result, it is possible to provide a taste with less bitterness similar to that of high-quality tea leaves. In addition, according to the method for producing powdered tea according to the present invention, since the bitterness and astringency of tea leaves are reduced, a powdered tea leaf (tea tea leaves) that normally has a strong bitter taste and cannot be drunk (decoction) Since it is possible to drink as it is (not a method of making food), all the nutritional components contained in the tea leaves can be taken into the body efficiently and in large quantities.

  The method for producing powdered tea according to the present invention is characterized by having a step of roasting and finely crushing tea, or a step of roasting matcha. In addition, strawberry tea as used in the present invention means that tea leaves covered with chanoki (Scientific name Camellia sinensis, camellia genus Camellia) are steamed and dried without twisting, and only the mesophyll is selected. This refers to the mesophyll (that is, the one that does not contain veins and stems) that has been coarsely crushed so that the length (maximum length) is about 5 mm, and so-called tailored leaves (crushed material) Equivalent to. Matcha tea is obtained by pulverizing the tea with a tea mill or the like. On the other hand, fine pulverization means that the roasted tea is finely pulverized so that the particle size is about 100 μm or less (preferably 1 to 20 μm) (usually, the tea Matcha can be obtained by fine grinding).

  The roasting referred to in the present invention is 16% RH to 50% RH (relative humidity), about 20 ° C. ± 5 ° C., using a roasting pan (Horocunabe), clay pot, fry pan, and other tea leaf storage equipment. In this atmosphere, the tea leaves (that is, tea tea or matcha tea) are heated by a heating device without being subjected to an open flame. In addition, as a heating apparatus, when a tea leaf is a small amount, Gotoku etc. can be used suitably, and when a tea leaf is abundant, a large-sized heating apparatus using a gas burner etc. can be used. .

  By roasting persimmon tea and matcha tea, it becomes possible to reduce catechins, caffeine, arginine, and the like, which are components that cause bitter and astringent taste. Moreover, it becomes possible to produce aroma components pyrazines, pyrroles, furans, and furfurals by roasting. Moreover, an amino compound and a reducing sugar turn into an aminocarbonyl reaction product which is an umami component by Maillard reaction, and a reducing sugar produces | generates a caramelization product. In addition, catechins become heat-modified catechin oxides by roasting as described above. In addition, by roasting as described above, caramelized products in tea leaves are increased due to the oxidation reaction of carbohydrates and sugars, and together with aminocarbonyl reaction products and catechin oxides, the umami and nourishment of powdered tea is increased. It becomes mitigation.

  The roasting temperature is preferably 100 ° C. or higher and 180 ° C. or lower, and more preferably 160 ° C. or higher and 180 ° C. or lower. That is, roasting within the range of 100 ° C. or higher and 180 ° C. or lower is effective in reducing the bitter taste of powdered tea, and roasting within the range of 160 ° C. or higher and 180 ° C. or lower is effective for scenting powdered tea. It is effective in increasing the height. The roasting time varies depending on the roasting temperature, but when roasting is performed within the range of 100 ° C. or more and less than 160 ° C., the length is preferably 3 minutes or more and 30 minutes or less, and 160 ° C. or more. When roasting within a range of 180 ° C. or lower, the length is preferably 2 minutes or longer and 20 minutes or shorter. In addition, the roasting is preferably performed in an environment of 1 atm with a humidity of 16% RH or more and 50% RH or less. Moreover, it is preferable to adjust roasting time according to liking, paying attention to the change of the color and aroma of a tea leaf raw material.

Furthermore, it is more preferable that roasting satisfies the following requirements (1) to (3).
(1) Reduce the content of tannin in roasted tea or matcha before roasting by 40% or more (2) Reduce content of caffeine in roasted tea or matcha before roasting by 40% or more (3) Do not reduce the content of theanine in roasted tea or matcha before roasting by 70% or more. Powdered tea obtained by roasting roasted tea or matcha so as to satisfy the above requirement (1) has a tannin content. And less bitter and astringent, and the formation of catechin oxide reduces the thickening. By roasting so as to satisfy the requirement of (2) above, the resulting powdered tea can be drunk even by infants, children, elderly people, insomnia, etc. with low caffeine content and no bitterness. By roasting so as to satisfy the requirement of (3), the obtained powdered tea has the original umami taste of theanine and the umami taste of the aminocarbonyl reaction product produced by roasting. The roasting is more preferably performed by reducing the content of tannin and / or caffeine in the tea or green tea before roasting by 50% or more.

  On the other hand, fine pulverization of roasted tea after roasting is preferably performed under a constant temperature and humidity condition of 10 ° C. to 20 ° C. at a humidity of 16% RH to 50% RH. In addition, the fine pulverization can be performed using a hand grinding mill or an electric mill, or can be performed using various mills.

  In the method for producing powdered tea according to the present invention, the content of all free amino acids in the tea or green tea before roasting is 2.5% or more and 6.2% or less, and the content of tannin is 7%. When the ratio is 0% or more and 13% or less, the effect obtained by roasting is particularly great when roasted tea or matcha is not a so-called "high-quality green tea or matcha", reducing bitterness and aroma, It is possible to make a great contribution to the increase in the refreshing taste that is not worried about thickening.

  EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the embodiments of the examples, and can be appropriately changed without departing from the spirit of the present invention. is there. For example, in the following examples, tea leaves stored in a roasting pan are roasted by heating with five virtues, but when industrialized, tea leaf storage equipment and heating equipment are large-sized that produce the same effect. Can be changed. In addition, the method for evaluating the characteristics of powdered tea in Examples and Comparative Examples is as follows.

<Evaluation of ingredients>
In the following Examples 1 to 8 and Comparative Examples 1, 2, and 3, each component of tannin, caffeine, and theanine contained in powdered tea before and after roasting treatment of strawberry tea, matcha tea and stem tea was used as a tea component analyzer. (Shizuoka Seisakusho Co., Ltd. GT-8) was used to investigate by near infrared spectroscopy. Further, catechin oxide was measured by a high performance fluid chromatographic method.

<Taste evaluation>
About 3 g of the obtained powdered tea was weighed, poured into 50 ml of hot water at about 70 ° C., and stirred to disperse the powdered tea in hot water to obtain a drink (tea). And the drink was drunk and the taste was sensory-evaluated from the following three viewpoints. In addition, sensory evaluation was performed by five different persons separately, and a large number (one of ◯, Δ, ×) was used as the final evaluation result.
[fragrance]
○ ・ ・ Those with the original fragrance of tea, or those with a roasting fragrance △ ・ ・ Low-scented fragrances × ・ ・ Slightly scented, or those with a burnt fragrance [Savor]
○ ・ ・ Those that feel the original taste of tea, or those that feel the taste of roasted tea △ ・ ・ Low-satisfaction level × ・ ・ Negligible taste [bitterness]
○ ・ ・ Slightly bitter taste △ ・ ・ Slight bitter taste × ・ ・ Slight bitter taste [Thoromi]
○ ・ ・ Thickness does not matter △ ・ ・ Thickness is reduced × ・ ・ Thoroughness

<Example 1>
About 100 g of tea plantation-produced cocoon tea (covered cultivated undercover tea leaves as raw materials, dried without dripping the tea leaves, except for leaf veins and stems) using a roasting pan at 20 ° C. Under an atmosphere of 45% RH, roasting was performed at a temperature of about 80 ° C. for 20 minutes using Gotoku. The roasted tea after the roasting was finely pulverized into a powder having a particle size of about 5 μm in an atmosphere of 20 ° C. and 45% RH to obtain the powdered tea of Example 1. And the component, taste, etc. of the obtained powder tea were evaluated by the above-mentioned method. In addition, the ingredients of tea leaves (roasted tea) before roasting were also evaluated. The evaluation results of the powdered tea of Example 1 are shown in Table 1.

<Example 2>
A powdered tea of Example 2 was obtained in the same manner as in Example 1 except that the roasting temperature was changed to 110 ° C. and the roasting time was changed to 10 minutes. The obtained powdered tea was evaluated by the same method as in Example 1. The evaluation results of the powdered tea of Example 2 are shown in Table 1.

<Example 3>
A powdered tea of Example 3 was obtained in the same manner as in Example 1 except that the roasting temperature was changed to 160 ° C. and the roasting time was changed to 5 minutes. The obtained powdered tea was evaluated by the same method as in Example 1. The evaluation results of the powdered tea of Example 3 are shown in Table 1.

<Example 4>
A powdered tea of Example 4 was obtained in the same manner as Example 3 except that the roasting temperature was changed to 180 ° C. and the roasting time was changed to 3 minutes. The obtained powdered tea was evaluated by the same method as in Example 1. The evaluation results of the powdered tea of Example 4 are shown in Table 1.

<Example 5>
A powdered tea of Example 5 was obtained in the same manner as Example 3 except that the roasting temperature was changed to 200 ° C. and the roasting time was changed to 2 minutes. The obtained powdered tea was evaluated by the same method as in Example 1. The evaluation results of the powdered tea of Example 5 are shown in Table 1.

<Example 6>
About 100 g of matcha tea was roasted using a roasting pan in an atmosphere of 20 ° C. × 45% RH at a temperature of about 110 ° C. for 10 minutes using Gotoku (powdered tea of Example 6) Roasted matcha) was obtained. The content of total free amino acids in the green tea before roasting was about 4%, and the content of tannin was about 10%. And the component, taste, etc. of the obtained powder tea were evaluated by the above-mentioned method. In addition, the components of tea leaves (green tea) before roasting were also evaluated. The evaluation results of the powdered tea of Example 6 are shown in Table 1 together with the production method.

<Example 7>
A powdered tea of Example 7 was obtained in the same manner as Example 6 except that the roasting temperature was changed to 160 ° C. and the roasting time was changed to 3 minutes. The obtained powdered tea was evaluated by the same method as in Example 1. The evaluation results of the powdered tea of Example 7 are shown in Table 1.

<Example 8>
Example 1 except that the tea leaves before roasting were changed to stem tea (tea leaves mainly composed of stem sticks), the roasting temperature was changed to 170 ° C., and the roasting time was changed to 15 minutes. Thus, powdered tea of Example 8 was obtained. The obtained powdered tea was evaluated by the same method as in Example 1. In addition, the components of tea leaves (stem tea) before roasting were also evaluated. The evaluation results of the powdered tea of Example 8 are shown in Table 1.

<Comparative Example 1>
A powdered tea of Comparative Example 1 was obtained in the same manner as in Example 1 except that the tea was not roasted. The obtained powdered tea was evaluated by the same method as in Example 1. Table 1 shows the evaluation results of the powdered tea of Comparative Example 1.

<Comparative example 2>
A powdered tea of Comparative Example 2 was obtained in the same manner as in Example 6 except that the green tea was not roasted. The obtained powdered tea was evaluated by the same method as in Example 1. The evaluation results of the powdered tea of Comparative Example 2 are shown in Table 1.

<Comparative Example 3>
A powdered tea of Comparative Example 3 was obtained in the same manner as in Example 1 except that the stem tea was not roasted. The obtained powdered tea was evaluated by the same method as in Example 1. The evaluation results of the powdered tea of Comparative Example 3 are shown in Table 1.

  From Table 1, it can be seen that the powdered teas of Examples 1 to 8 subjected to the roasting treatment are good in aroma, nourishment and bitterness and are suitable for drinking with reduced thickening. Furthermore, it turns out that the powder tea of Examples 2-4, 6-8 which adjusted the roasting temperature to 110 to 180 degreeC is especially favorable also in aroma | smelling, nourishment, bitterness and astringency reduction. In addition, the powdered teas of Examples 1 to 4 subjected to the roasting treatment (those made from tea tea as a raw material) were tea leaves before roasting (Comparative Example 1) except for Example 1 which was roasted at 80 ° C. Compared to the above, it can be seen that the tannin content is reduced by 40% or more, the caffeine content is reduced by 40% or more, and the theanine content is not reduced by 70% or more. In addition, the powdered teas of Examples 6 and 7 in which matcha was roasted were also reduced by 40% or more in tannin content compared to the tea leaves before roasting, similar to the powdered teas of Examples 2 to 4. It can be seen that the content of caffeine is reduced by 40% or more and the content of theanine is not reduced by 70% or more. Furthermore, the powdered tea of Example 8 (which uses stem tea as a raw material) subjected to the roasting treatment also has a tannin content as compared with the tea leaves before roasting, similar to the powdered tea of Examples 2-4. Is reduced by 40% or more, the caffeine content is reduced by 40% or more, and the theanine content is not reduced by 70% or more. In addition, it turns out that the powder tea of Example 1 whose roasting temperature is 80 degreeC roasted at 100 degrees C or less does not show a big change in the content rate of a tannin, caffeine, and theanine. Furthermore, in the powder teas of Examples 2 to 8 in which the roasting temperature was adjusted to 110 ° C. to 200 ° C., an increase in catechin oxide was observed, which indicates that this corresponds to a reduction in thickening.

  In comparison, it can be seen that the powdered teas of Comparative Examples 1 to 3 in which the tea leaves were not roasted were poor in both taste and bitterness and unsuitable for drinking as powdered tea. Moreover, it turns out that the powder tea of Comparative Examples 1-3 which did not perform a roasting process does not show a big change in the content rate of a tannin, caffeine, theanine, and a catechin oxide.

  Since the method for producing powdered tea having the roasting process of the present invention has excellent effects as described above, it is preferably used as a method for changing inexpensive tea, matcha tea and stem tea to powder tea that is delicious and easy to drink. Can do.

Claims (4)

A method for producing powdered tea that can be dispersed in hot water and drinkable,
A method for producing powdered tea, comprising a step of roasting and finely pulverizing tea, or a step of roasting matcha tea.   The method for producing powdered tea according to claim 1, wherein the roasting temperature is 100 ° C or higher and 180 ° C or lower.   The content of all free amino acids in the tea or matcha before roasting is 2.5% or more and 6.2% or less, and the content of tannin is 7.0% or more and 13.0% or less. The method for producing powdered tea according to claim 1 or 2, characterized in that The method for producing powdered tea according to any one of claims 1 to 3, wherein the roasting satisfies the following requirements (1) to (3).
(1) Reduce the content of tannin in roasted tea or matcha before roasting by 40% or more (2) Reduce content of caffeine in roasted tea or matcha before roasting by 40% or more (3) Do not decrease the content of theanine in roasted tea or matcha before roasting by more than 70%