JP2016086676A - Decaffeinated powdered tea, method for producing the same, and decaffeination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide decaffeinated powdered tea reduced in deterioration of the original flavor and color tone of powdered tea, a method for producing the same, and a decaffeination device to be used for the decaffeinated powdered tea producing method.SOLUTION: A method for producing decaffeinated powdered tea includes: preparing as the raw material, finished leaves of Tencha tea and powdered tea; extracting the raw material with cold water so as to obtain a raw material extract and a raw material residue; bringing the raw material extract into contact with a porous polymerization resin so as to obtain a caffeine-reduced solution; and freeze-drying the raw material residue and the caffeine-reduced solution. The decaffeinated powdered tea suppressed in deterioration of flavor and color tone can be produced by extracting a raw material with cold water, and removing caffeine with a porous polymerization resin followed by freeze-drying.SELECTED DRAWING: Figure 1

Description

  The present invention relates to decaffeinated matcha with little deterioration of the original flavor and color tone of matcha, a method for producing the same, and a decaffeination processing apparatus.

  Good quality matcha has a strong taste, astringency and bitterness, a faint sweet scent, and a vivid green hue. The taste is strong because matcha contains a large amount of theanine. Matcha contains a lot of caffeine.

  In Europe and the United States, decaffeinated coffee has been produced for people who want to avoid caffeine consumption. At the time of production, methods such as an organic solvent extraction method, a Swiss water extraction method, and a supercritical carbon dioxide extraction method have been used for decaffeination. It is conceivable to apply these methods to produce decaffeinated matcha.

  However, the organic solvents used in the organic solvent extraction method and the Swiss water extraction method are not included in the list that can be used in the Japanese food hygiene law, and further, the smell of the organic solvent impairs the faint aroma of matcha. . In the supercritical carbon dioxide extraction method, since the pigment component is extracted and removed, the matcha is faded.

  On the other hand, a method for producing solid tea with reduced caffeine content has been developed without using an organic solvent extraction method, a Swiss water extraction method, or a supercritical carbon dioxide extraction method (Patent Literature). 1). If the method described in Patent Document 1 is taken, green tea is prepared as a raw material, the raw material is extracted with water or ethanol, heat-treated, caffeine leached from the raw material is distilled off together with water or ethanol, and decaffeinated. Matcha tea can be produced.

Japanese Patent Laid-Open No. 2008-212024

  However, when decaffeinated matcha is produced by a conventional method, there is a problem that the original flavor and color tone of matcha are impaired.

  Then, an object of this invention is to provide the decaffeinated matcha with little deterioration of the original flavor and color tone of Matcha, and its manufacturing method. Furthermore, this invention aims at providing the decaffeination processing apparatus used with the manufacturing method of the above-mentioned decaffeinated matcha tea.

  In order to achieve the above object, a method for producing decaffeinated matcha according to the present invention comprises a step of preparing a raw material selected from the group consisting of tailored leaves of green tea, matcha and a mixture thereof, and the raw material is cold water. Extraction step to obtain a raw material extract and a raw material or raw material residue during extraction, and decaffeine to adsorb caffeine by contacting the raw material extract with a porous polymer resin to obtain a caffeine reducing solution And a step of freeze-drying the raw material residue and the caffeine reducing solution to obtain a dried product of the raw material residue and a dried product of the caffeine reducing solution.

  Moreover, it is comprised so that the said cold water may be 10 degrees C or less.

  The drying step is configured to freeze-dry the mixture of the raw material residue and the caffeine reducing liquid.

  An extraction continuation step of sending the caffeine reducing liquid to the raw material during extraction, extracting the raw material during extraction with the caffeine reducing liquid to obtain the raw material extract, the extraction continuation step, and the decaffeination It is comprised so that the process may be repeated and the liquid circulation process of obtaining the mixture of the said raw material residue and the said caffeine reduction liquid may be included.

  The decaffeinated matcha according to the present invention is configured to be obtained by the method for producing decaffeinated matcha.

  Furthermore, the decaffeination processing apparatus according to the present invention extracts a raw material selected from the group consisting of tailored tea leaves, matcha tea and a mixture thereof with cold water or a caffeine reducing liquid, a raw material extract, and an extraction An extraction tank for obtaining a raw material or a raw material residue on the way, a porous polymer resin for contacting the raw material extract to adsorb caffeine and obtaining the caffeine reducing liquid, and sending the caffeine reducing liquid to the extraction tank And a liquid means.

  Moreover, it is comprised so that the precipitation tank provided in the downward direction of the said extraction tank and the filter provided so that the said raw material extraction liquid may pass before contacting the said porous polymerization resin are comprised.

  In the method for producing decaffeinated matcha according to the present invention having the above-described structure, the caffeine contained in the tea leaves and matcha used as raw materials is leached in cold water and then adsorbed and removed by the porous polymer resin. . For this reason, decaffeinated matcha has a reduced content of caffeine derived from the raw material. Here, decaffeinated means a state in which a part of caffeine is removed and the content of caffeine is reduced.

  Further, in the method for producing decaffeinated matcha according to the present invention, the raw material is extracted with cold water, and the raw material residue and the caffeine reducing liquid are freeze-dried. Therefore, the decomposition of theanine and the reduction of the scent component can be suppressed. In addition, since decaffeinated matcha is produced using both the raw material residue and the caffeine reducing liquid, decaffeinated matcha contains not only the ingredients of the raw material residue but also components that have been transferred to the caffeine reducing liquid. It has been recovered. For this reason, decaffeinated matcha is one in which theanine and scent components derived from the raw material are preserved.

  In the method for producing decaffeinated matcha according to the present invention, alteration of the pigment component can be suppressed by extracting the raw material with cold water. Furthermore, since the raw material residue and the caffeine reducing liquid are dried by freeze-drying, it is possible to avoid deterioration of the pigment component during drying. For this reason, the decaffeinated matcha has a vivid green color tone.

  Therefore, according to the present invention, there are provided decaffeinated matcha with little deterioration of the original flavor and color tone of matcha and a method for producing the same. Furthermore, according to this invention, the decaffeination processing apparatus used with the manufacturing method of decaffeinated matcha is provided.

Flowchart of a method for producing decaffeinated matcha according to Embodiment 1 Flowchart of a method for producing decaffeinated matcha according to Embodiment 2 Flowchart of a method for producing decaffeinated matcha according to Embodiment 3 Sectional end view of the apparatus representing one embodiment of a decaffeinated processing apparatus used in the method for producing decaffeinated matcha according to Embodiment 3 Sectional end view of the apparatus representing another form of the decaffeinated processing apparatus used in the method for producing decaffeinated matcha according to Embodiment 4 Sectional end view of the apparatus representing another form of the decaffeinated processing apparatus used in the method for producing decaffeinated matcha according to Embodiment 5

[Embodiment 1]
The method for producing decaffeinated matcha shown in FIG. 1 includes a step of preparing raw materials, an extraction step, a decaffeination step, and a drying step.

  In the step of preparing the raw material, either a tailored tea leaves, matcha tea, or a mixture of tailored tea leaves and green tea is prepared as a raw material for decaffeinated matcha. Depending on the degree of processing, the tea has a stage that is a rough tea of the tea and a stage that is a tailored leaf of the tea. The rough tea of 荒 茶 is a tea leaf that has been plucked from a tea tree that has been light-shielded and cultivated for 2 to 3 weeks before plucking, and the plucked fresh tea leaf is steamed and dried without simmering the steamed leaf. The tailored tea leaves are obtained by cutting rough tea leaves, separating stems and veins, and selecting mesophyll parts from the cut pieces. For example, the tea leaves are about 3 to 5 mm in one side.

  Green tea, the raw material, is a powder obtained by pulverizing tea leaves with a grinding mill, and has not yet been decaffeinated. An electric mill can be used as the milling mill used when preparing the matcha, but a hand milling mill is preferable in order to suppress thermal denaturation of theanine and scent components. The raw material matcha tea is preferably obtained by crushing tailored tea leaves with a grinding mortar and then removing the impurities by a sieve. The particle size of the raw material matcha is, for example, about 1 to 20 μm.

  When preparing a mixture of tea leaves and matcha tea as a raw material, there is no particular limitation on the mixing ratio of tea leaves and matcha tea.

  In detail, the extraction process of the manufacturing method shown in FIG. 1 is performed in the order of the first extraction process, the second extraction process, and the third extraction process. In the extraction step, the raw material is put in a filter bag, the raw material is immersed in cold water together with the bag, and the raw material is extracted with cold water.

  Cold water used for extraction is distilled water, ion exchange water, tap water, natural water, etc., and the water temperature is 15 ° C. or less. Even if the water temperature is 15 ° C. or lower, if the raw material is immersed in cold water over 30 minutes, most of the caffeine contained in the raw material is leached into the cold water.

  However, when cold water in contact with the raw material solidifies into ice, caffeine leaching does not progress. When the water temperature is higher than 15 ° C., the color tone of the raw material or the raw material extract is likely to deteriorate during extraction, so that the decaffeinated matcha tea may be deteriorated in color tone. On the other hand, when the temperature is higher than 15 ° C., various germs are likely to propagate on the raw material.

  The water temperature of the cold water is preferably 10 ° C. or lower. When the temperature is 10 ° C. or lower, the deterioration of the color tone of the raw material and the raw material extract becomes extremely slow during the extraction, and thus the decaffeinated matcha tea is particularly suppressed in the deterioration of the color tone. Moreover, when it is 10 degrees C or less, it can suppress that a germ propagates to a raw material etc.

  The water temperature of the cold water is more preferably 5 ° C. or lower. When the temperature is 5 ° C. or lower, the deterioration of the color tone of the raw material and the raw material extract is further extremely delayed during the extraction. For example, even if it takes 72 hours to extract the raw material with cold water at 5 ° C or less, it produces decaffeinated matcha with a color tone suppressed to such an extent that it cannot be distinguished from undecaffeinated matcha. can do. Moreover, when it is 5 degrees C or less, it can further suppress that a germ germ propagates to a raw material etc.

  The shape, material, and configuration of the filtration bag are not particularly limited as long as cold water can pass through the bag and the raw material put in the bag can be prevented from flowing out. When matcha is not included in the prepared raw material, as the filtration bag, for example, a bag made of a filter cloth for food such as nylon, polyester, or cotton, a bag made of cloth such as flannel, , Bags made of paper for filtration, such as filter paper, paper filter used when brewing coffee, and pulp filter.

  When the prepared raw material contains matcha, it is better to use a filter bag made of fine cloth or paper, compared to the case where the raw material does not contain matcha. Examples of such a filtration bag include a filtration bag constituted by flannel, a filter paper, a paper filter used when brewing coffee, and a filtration bag constituted by filtration paper such as a pulp filter. The filter bag may have a structure in which a plurality of particularly fine cloths and papers are stacked. When a filtration bag made of fine cloth or paper is used, it is possible to prevent the raw material matcha from flowing out of the filtration bag during extraction. By preventing the matcha from flowing out, it is possible to avoid clogging the porous polymer resin due to the matcha that has flowed out in the subsequent decaffeination step.

  In the first extraction step, cold water is stored in the first extraction tank, the raw material is immersed in the cold water together with the bag, and the raw material is extracted with cold water. After a certain period of time, the bag and the raw material are taken out from the cold water, and the raw material is drained. Caffeine that could not be leached into the cold water remains in the raw material after being taken out of the cold water. For this reason, the raw material taken out from the cold water and drained is handled as a raw material during extraction.

  In the second extraction step, cold water is stored in the second extraction tank, the whole raw material for extraction is immersed in cold water together with the bag, and the raw material for extraction is extracted with cold water. After a certain period of time, the raw material in the middle of extraction is taken out from the cold water together with the bag, and the raw material in the middle of extraction is drained. Caffeine that could not be leached into cold water remains in the raw material during extraction after being taken out from cold water. For this reason, the extraction raw material taken out from the cold water and drained in the second extraction step is also handled as the extraction intermediate raw material.

  In the third extraction step, cold water is stored in the third extraction tank, the raw material during extraction after the second extraction step is immersed in the cold water together with the bag, and the raw material during extraction is extracted with cold water. After a certain period of time, the raw material in the middle of extraction is taken out from the cold water together with the bag, and the raw material in the middle of extraction is drained. In the third extraction step, since caffeine further leached from the raw material during extraction, the content of caffeine in the raw material during extraction is sufficiently reduced compared to the raw material before extraction. For this reason, the extraction raw material taken out from the cold water and drained in the third extraction step is handled as a raw material residue.

  After finishing each step of the first extraction step, the second extraction step, and the third extraction step, the first extraction tank, the second extraction tank, and the third extraction tank are either raw materials or during extraction Cold water containing components such as caffeine leached from the raw material is left. These cold waters are mixed, and the resulting mixed liquid is handled as a raw material extract. In the extraction process of the manufacturing method shown in FIG. 1, the raw material residue and the raw material extract are obtained through the first extraction process, the second extraction process, and the third extraction process.

  In the extraction, it is preferable to use a total of 15 to 45 parts by weight of cold water with respect to 1 part by weight of the raw material. If the total amount is less than 15 parts by weight, since the amount of cold water is small, caffeine contained in the raw material is not sufficiently leached. If the total amount is more than 45 parts by weight, a large amount of the raw material extract is obtained, which increases labor and cost in the subsequent drying step.

  In the extraction process, for example, 10 parts by weight of cold water is used in each of the first extraction process, the second extraction process, and the third extraction process with respect to 1 part by weight of the raw material, so that a total of 30 parts by weight of cold water is used. The extraction efficiency of caffeine depends on the difference between the concentration of caffeine contained in the raw material or raw material during extraction and the concentration of caffeine contained in cold water. Rather than extracting once with 30 parts by weight of cold water, it is better to extract three times with 10 parts by weight of cold water in each of the first extraction step, the second extraction step, and the third extraction step. Since there are three chances of extraction with cold water that does not contain caffeine at all, the extraction efficiency of caffeine is good.

  In the extraction process of the manufacturing method illustrated in FIG. 1, a three-stage process including a first extraction process, a second extraction process, and a third extraction process is performed, but the extraction process is not limited to a three-stage process. The extraction process may further include multi-stage processes, for example, a fourth extraction process and a fifth extraction process.

  During extraction, ice or cold water may be added to the extraction tank as necessary. The length of the extraction time is set so that the total extraction time is 30 minutes or more and 72 hours or less throughout the extraction process in order to sufficiently extract caffeine contained in the raw material. If it is less than 30 minutes, the extraction time is too short, and it is difficult to sufficiently leach caffeine contained in the raw material. If it is longer than 72 hours, there is a risk that germs will propagate in the raw material.

  When the prepared raw material is matcha, the extraction efficiency of caffeine is better in the extraction process than when the raw material is tailored leaves of strawberry tea. This is because matcha has a larger surface area per unit weight than tailed tea leaves. When the prepared raw material is matcha, it is possible to produce decaffeinated matcha in which the content of caffeine is further reduced as compared with the case where the raw material is tailored leaves of strawberry tea.

  In the decaffeination step, the raw material extract is brought into contact with the porous polymer resin. Thereby, caffeine contained in the raw material extract is adsorbed to the porous polymer resin. The raw material extract after contact with the porous polymer resin becomes a caffeine reducing liquid in which the content of caffeine is reduced.

  When the prepared raw material does not contain matcha, the method for bringing the raw material extract into contact with the porous polymer resin is not particularly limited. For example, a method in which a column filled with a porous polymer resin is prepared, and a raw material extract is allowed to flow through the column and passed through. At this time, the flow rate of the raw material extract passing through the column is appropriately set so that caffeine contained in the raw material extract is efficiently adsorbed with the porous polymer resin.

  When the prepared raw material contains matcha, it is desirable to protect the porous polymer resin so that the matcha does not come into contact when the matcha flows out of the filtration bag. For this reason, when green tea is contained in the prepared raw material, it is preferable to pass the raw material extract through the filter and bring the raw material extract that has passed through the filter into contact with the porous polymer resin. Even if the raw material extract contains fine fibers derived from matcha tea that has flowed out or tailed tea leaves, it can be avoided by being clogged by the porous polymer resin because it is scraped off by the filter. .

  Filters for protecting the porous polymer resin include filter paper, paper filters used when brewing coffee, paper filters for filtration such as pulp filters, fine cloth filters such as flannel, synthetic resin Examples thereof include filters and glass fiber filters. For example, since matcha cannot pass through a filter paper or paper filter and is scraped off, if a filter having a filtration density similar to that of the filter paper or paper filter is used, it is possible to avoid clogging the porous polymer resin.

  The filter for protecting the porous polymer resin is more preferably a filter paper, a paper filter used when brewing coffee, a paper filter for filtration such as a pulp filter, or a filter made of fine cloth such as flannel. is there. Since these filters are inexpensive and readily available, a large number of spares can be prepared. For this reason, even if the filter is clogged with scraped green tea, it can be immediately replaced with a spare filter and the decaffeination process can be resumed.

  The porous polymer resin is mainly made of a material that adsorbs caffeine but hardly adsorbs theanine. Examples of the polymer resin constituting the porous polymer resin include a styrene-based or acrylic cross-linked polymer, a copolymer of styrene and divinylbenzene, a methacrylic ester resin, a polycondensation polymer of methacrylic acid and a diol, and the like. be able to. Examples of the structure of the porous polymer resin include a porous type having a micropore and a macropore, a high porous type, and an MR (macro-reticular) type. Specific examples of the porous polymer resin include Amberlite XAD such as Diaion HP series, Sepabead SP series (manufactured by Mitsubishi Chemical Corporation), Amberlite XAD-4, Amberlite FPX66, Amberlite XAD-1180N, and the like. A synthetic adsorbent such as a series (made by Dow Chemical Co., Ltd.) can be used.

  More preferably, the porous polymer resin is made of a material that selectively adsorbs caffeine and does not readily adsorb components other than caffeine contained in the raw material extract, not limited to theanine. Specific examples of such a porous polymer resin include synthetic adsorbents such as Amberlite FPX66 (manufactured by Dow Chemical Co.). If a porous polymer resin that selectively adsorbs caffeine and does not readily adsorb components other than caffeine is used, components that have leached from ingredients other than caffeine are not removed. It becomes possible to produce decaffeinated matcha tea with particularly little deterioration.

  When the decaffeination process is repeated and the porous polymer resin cannot adsorb a larger amount of caffeine, the porous polymer resin is washed with an aqueous alcohol solution such as an ethanol aqueous solution. When washed, components such as caffeine are removed from the porous polymer resin, so that the porous polymer resin can be regenerated. Note that caffeine obtained by washing can be used as a food additive or the like.

  The above-described extraction step and decaffeination step are preferably performed by providing an extraction tank and a porous polymer resin in a refrigerator room having a temperature higher than 0 ° C and not higher than 15 ° C. The temperature management is easier when the extraction step and the decaffeination step are performed in the refrigerator than when the cooling device is used for cooling. In order to extremely suppress the deterioration of the color tone of the raw material and the raw material extract, the room temperature of the refrigerator compartment is more preferably higher than 0 ° C. and not higher than 10 ° C., still more preferably higher than 0 ° C. and not higher than 5 ° C.

  In the drying step, each of the raw material residue and the caffeine reducing solution is separately lyophilized to remove moisture using a freeze dryer. By freeze-drying, a dried product of the raw material residue is obtained from the raw material residue, and a dried product of the caffeine reducing solution is obtained from the caffeine reducing solution.

  If the prepared raw material contains tailored tea leaves, after the drying step, a grinding step is used to grind the dried material residue to obtain a dry powder of the raw material residue. As the grinding mill used in the drying process, an electric mill is used, and a hand milling mill is more preferable in order to suppress thermal denaturation of theanine and fragrance components. When the prepared raw material is only matcha, the dried material residue obtained in the drying step is already a dry powder, so that the pulverization step can be omitted. After the pulverization step, a mixing step is performed in which the dry powder of the raw material residue and the dried product of the caffeine reducing liquid are mixed using a stirrer, a spatula, or the like. The powder obtained in the mixing process is handled as decaffeinated matcha.

  As a method for producing decaffeinated matcha, a method of extracting the raw material with ethanol is also conceivable. However, even after freeze-drying, it is difficult to completely remove ethanol that has penetrated into the raw material residue, so that decaffeinated green tea contains a trace amount of ethanol. In this case, when decaffeinated matcha is used to make matcha, ethanol warmed with hot water is vaporized, and the smell of ethanol will damage the faint aroma of matcha.

  As a method for producing decaffeinated matcha, a method in which the raw material is extracted with hot water or acidic warm water to reduce the content of caffeine in the raw material or the raw material extract is also conceivable. However, when the raw material is extracted with hot water or acidic warm water, theanine is decomposed or the pigment component is altered. Although the method of adding ascorbic acid to hot water or warm water in order to suppress the alteration of the components is also conceivable, if the amount added is large, the original flavor of matcha is impaired.

  On the other hand, when the above-described extraction process is performed, caffeine contained in the raw material is leached into cold water and transferred to the raw material extract. Furthermore, when the above-described decaffeination step is performed, the caffeine transferred to the raw material extract is adsorbed on the porous polymerization resin. For this reason, the raw material extract becomes a caffeine reducing liquid in which the content of caffeine is selectively reduced. Decaffeinated matcha tea produced using both the raw material residue and the caffeine reducing liquid is produced according to standards that satisfy the Food Sanitation Law, and the content of caffeine derived from the raw material is reduced.

  Moreover, since the raw material is extracted with cold water in the extraction step and the raw material residue and the caffeine reducing liquid are freeze-dried in the drying step, decomposition of theanine and a decrease in the scent component can be suppressed. In addition, since decaffeinated matcha is produced using not only the raw material residue but also the caffeine reducing liquid, the decaffeinated matcha contains not only the ingredients of the raw material residue but also the theanine that has been transferred to the caffeine reducing liquid. Ingredients such as fragrance and potassium are recovered. Decaffeinated green tea retains theanine and scent components derived from the raw materials.

  When tailored tea leaves or matcha tea comes into contact with water, there is a phenomenon that the color tone of the raw materials and raw material extract deteriorates from green to red. This phenomenon was suppressed by extracting the raw material with cold water in the extraction process. In addition, since the raw material residue and the caffeine reducing liquid are dried by freeze-drying in the drying process, the pigment component is prevented from being altered during the drying. Decaffeinated green tea retains its vibrant green color.

  Therefore, the production method shown in FIG. 1 makes it possible to produce decaffeinated matcha with little deterioration of the original flavor and color tone of matcha.

  If the theanine content of decaffeinated matcha is 70% or higher compared to the theanine content of green tea that has not yet been decaffeinated, add hot water to each matcha and turn on the matcha. Compared to drinking, it is difficult to recognize that decaffeinated matcha has reduced umami ingredients. For example, when the raw material is extracted with cold water at 15 ° C. for 30 minutes in the extraction process, the decaffeinated matcha tea obtained by the production method of FIG. 1 is such that 80% or more of the theanine content is retained. It is difficult to recognize that the component is decreasing.

  In addition, when the raw material is extracted with cold water at 15 ° C. for 30 minutes in the extraction process, decaffeinated matcha obtained by the production method of FIG. 1 is more caffeinated than matcha that has not been decaffeinated. The content is reduced to less than 40%, and it becomes difficult to visually recognize the difference in hue. It is difficult to recognize that this decaffeinated matcha is deteriorating in its original flavor and hue unless care is taken.

  When the raw material is extracted with cold water at 10 ° C. or lower for 5 hours in the extraction process, the decaffeinated matcha obtained by the production method of FIG. 1 contains caffeine compared to the matcha that has not been decaffeinated. The amount is reduced to less than 20%, and it is extremely difficult to recognize a difference in color visually, and the theanine content is maintained at 80% or more. Even if care is taken with this decaffeinated matcha, it is difficult to recognize that the original flavor and color of the matcha have deteriorated.

[Embodiment 2]
As for the method for producing decaffeinated matcha shown in FIG. 2, only the configuration and operational effects different from those of the production method shown in FIG. Compared with the manufacturing method shown in FIG. 1, the manufacturing method shown in FIG. 2 is performed in the order of the mixing step, the drying step, and the pulverizing step after the decaffeination step.

  In the mixing step of the manufacturing method shown in FIG. 2, the raw material residue and the caffeine reducing liquid are mixed to obtain a mixture of the raw material residue and the caffeine reducing liquid. At the time of mixing, since the amount of the caffeine reducing liquid is larger than the amount of the raw material residue, the mixture is in a state where the raw material residue is immersed in the caffeine reducing liquid.

  In the drying step, the mixture of the raw material residue and the caffeine reducing liquid is lyophilized by using a freeze dryer to remove moisture, and a mixed dried material of the raw material residue and the caffeine reducing liquid is obtained. The mixed dried product obtained after freeze-drying is a state in which a dry powder of components leached from the raw material adheres to the surface of the dried material residue. When the prepared raw material is only matcha, the pulverization step can be omitted, and the mixed dried product obtained in the drying step may be handled as decaffeinated matcha.

  When tailored tea leaves are included in the prepared raw material, in the pulverization step, the mixed dried product of the raw material residue and the caffeine reducing liquid is pulverized using a grinding mill. Compared with the pulverization step of the manufacturing method shown in FIG. 1, the pulverization step of the manufacturing method shown in FIG. 2 differs in that the dried product of the caffeine reducing liquid is also pulverized and mixed with the dry powder of the raw material residue. The powder obtained by grinding with a grinding mill is handled as decaffeinated green tea.

  In the mixing step of the manufacturing method shown in FIG. 2, a part of the caffeine reducing liquid penetrates into the raw material residue and is integrated. In the drying process of the manufacturing method shown in FIG. 2, the caffeine reducing liquid that has not penetrated into the raw material residue adheres to the dry material of the raw material residue and is integrated during freeze-drying. For this reason, when the prepared raw material is only matcha tea and the mixed dried product obtained in the drying process is handled as decaffeinated matcha, the decaffeinated matcha is composed of the raw material residue component and the component leached from the raw material. It becomes what became.

  In addition, when the prepared raw material contains tailored tea leaves, in the pulverization step of the production method shown in FIG. 2, the mixed dry product is pulverized, so the decaffeinated matcha tea obtained after pulverization is The residue component and the component leached from the raw material are uniformly mixed.

  Therefore, if the manufacturing method shown in FIG. 2 is taken, decaffeinated matcha with little unevenness in flavor can be easily manufactured regardless of whether the prepared raw material is only matcha tea or when the raw material contains tailored tea leaves. Can do.

[Embodiment 3]
The manufacturing method shown in FIG. 3 using the decaffeination processing apparatus 1a shown in FIG. 4 will be described only with respect to the configuration and operational effects different from the manufacturing method shown in FIG. The decaffeination processing apparatus 1a shown in FIG. 4 is used to perform the extraction process, the decaffeination process, the extraction continuation process, and the liquid circulation process in the manufacturing method shown in FIG.

  Hereinafter, the configuration and operation effects of the decaffeination processing apparatus 1a shown in FIG. 4 and the manufacturing method shown in FIG. 3 will be described. The decaffeination processing apparatus 1a shown in FIG. 4 mainly includes an extraction tank 11a, a porous polymer resin 31, and a liquid feeding means 41.

  The extraction tank 11a shown in FIG. 4 has an open top surface, and a filter plate 14 is provided on the inner bottom surface. The raw material 2 is put into the filtration bag 13, the raw material 2 is placed together with the filter bag 13 so as to cover the entire upper surface of the filter plate 14, and the cold water 3 is put into the extraction tank 11 a, and the raw material 2 is extracted with the cold water 3. Can do.

  When the cold water 3 passes through the filter bag 13 and the raw material 2 and further passes through the filter plate 14, the cold water 3 becomes a raw material extract 5 containing components such as caffeine leached from the raw material 2. The raw material 2 is extracted with cold water 3 to reduce the content of caffeine, but there is still room for leaching caffeine. The raw material 2 extracted with the cold water 3 is handled as the raw material 4 during extraction. For this reason, in the extraction tank 11a, the extraction process which extracts the raw material 2 with the cold water 3 and obtains the raw material extract 5 and the extraction middle raw material 4 can be performed.

  The filtration bag 13 used in the decaffeination treatment apparatus 1a preferably has a size that can cover the entire upper surface of the filter plate 14 when the raw material 2 is placed in the bag 13 and placed on the filter plate 14. . Alternatively, the size of the filtration bag 13 may cover all of the upper surface of the filtration plate 14 when a plurality of bags are placed on the upper surface of the filtration plate 14. As shown in FIG. 4, a plurality of filtration bags 13 containing the raw material 2 therein may be stacked in the extraction layer 11a.

  The raw material extract 5 flows down the filter plate 14 and reaches the pipe 33. Since the porous polymer resin 31 is provided in the pipe 33, the raw material extract 5 comes into contact with the porous polymer resin 31. The porous polymer resin 31 in contact with the raw material extract 5 mainly adsorbs caffeine contained in the raw material extract 5. The raw material extract 5 becomes a caffeine reducing liquid 6 in which the content of caffeine is reduced. For this reason, in the porous polymerization resin 31, the decaffeination process which makes the raw material extract 5 contact with the porous polymerization resin 31, adsorbs caffeine, and obtains the caffeine reduction liquid 6 can be performed.

  The caffeine reducing liquid 6 obtained in contact with the porous polymer resin 31 reaches the liquid feed pump 42. The liquid feed pump 42 sends the caffeine reducing liquid 6 through the pipe 43 to the shower section 44 provided above the opened upper surface of the extraction tank 11a. The caffeine reducing liquid 6 sent to the shower unit 44 is discharged from the shower unit 44 into the storage tank 11a. For this reason, the structure which combined the liquid feeding pump 42, the piping 43, and the shower part 44 functions as the liquid feeding means 41 which sends the caffeine reduction liquid 6 from the porous polymerization resin 31 to the extraction tank 11a.

  The caffeine reducing liquid 6 released into the extraction tank 11a contains components such as caffeine leached from the extraction raw material 4 when it passes through the filtration bag 13 and the extraction raw material 4 and further passes through the filter plate 14. This is the raw material extract 5. Further, the raw material 4 during extraction is extracted with the caffeine reducing liquid 6 to reduce the content of caffeine, but there is still room for extracting caffeine. The extraction raw material 4 after being extracted with the caffeine reducing liquid 6 is also handled as the extraction intermediate raw material 4. For this reason, the caffeine reducing liquid 6 is sent from the porous polymerization resin 31 to the extraction intermediate raw material 4 by the liquid feeding means 41 and the extraction tank 11a, and the extraction raw material 4 is extracted with the caffeine reducing liquid 6 to obtain the raw material extraction liquid. 5 can be performed.

  The raw material extract 5 obtained in the extraction continuation step flows down below the filter plate 14 and reaches the porous polymer resin 31 via the pipe 33. For this reason, the decaffeination process is performed again with the porous polymer resin 31. Since the caffeine reducing liquid 6 obtained in the decaffeination process is sent into the extraction tank 11a by the liquid feeding means 41, it becomes the raw material extract 5 again in the extraction continuation process. If the extraction continuation step and the decaffeination step are repeated as described above, the content of caffeine contained in the raw material 4 during extraction can be sufficiently reduced. In addition, the caffeine reducing liquid 6 permeates into the raw material 4 during extraction in a form that replaces the extracted components such as caffeine.

  After repeating the extraction continuation step and the decaffeination step, the extraction raw material 4 that is taken out from the extraction tank 11 a together with the filter bag 13 and not drained is handled as a mixture of the raw material residue and the caffeine reducing liquid 6. In addition, a liquid circulation step of obtaining a mixture of the raw material residue and the caffeine reducing liquid by repeating the extraction continuation step and the decaffeination step by the extraction tank 11a, the porous polymer resin 31, and the liquid feeding means 41 is performed. it can.

  The mixture of the raw material residue and the caffeine reducing liquid 6 obtained in the liquid circulation step is taken out from the filter bag 13 and freeze-dried by a freeze dryer. The drying step of lyophilizing the mixture of the raw material residue and the caffeine reducing liquid 6 by a freeze dryer to obtain a mixture of the dried raw material residue and the dried caffeine reducing liquid 6 can be performed. Next, a grinding process of obtaining a decaffeinated green tea by grinding the mixture of the dried material residue and the dried caffeine reducing liquid 6 with a grinding mill can be performed.

  When the production method shown in FIG. 3 is performed using the decaffeination processing apparatus 1a, the caffeine contained in the raw material 4 during the extraction is repeatedly leached and the caffeine transferred to the raw material extract 5 is converted into the porous polymer resin 31. Is repeatedly removed. For this reason, when a liquid circulation process is performed for a long time, the caffeine content of the caffeine reducing liquid 6 is gradually reduced. In the liquid circulation step, caffeine continues to be efficiently leached from the raw material 4 during extraction depending on the difference between the concentration of caffeine contained in the raw material 4 during extraction and the concentration of caffeine contained in the caffeine reducing liquid 6. .

  Therefore, when the manufacturing method shown in FIG. 3 is performed using the decaffeination processing apparatus 1a, the extraction efficiency of caffeine is better than when the manufacturing method shown in FIGS. For this reason, for example, when the extraction process, the decaffeination process, the extraction continuation process, and the liquid circulation process are performed over a total of 3 hours, it is possible to produce decaffeinated matcha tea in which the content of caffeine is reduced by 80% or more. it can. Further, since the extraction efficiency of caffeine is good, a small amount of cold water 3 is required, and the amount of caffeine reducing liquid 6 is also small, so that the freeze-drying processing time can be shortened in the drying step, thereby reducing the cost.

  Furthermore, when the production method shown in FIG. 3 is performed using the decaffeination processing apparatus 1a, components such as theanine and catechins contained in the raw material 2 and the raw material 4 during extraction are leached and transferred to the raw material extract 5. . The content of caffeine in the raw material extract 5 is reduced by the decaffeination step, but the content of theanine and the like is not reduced. Through the liquid circulation process, the raw material extract 5 and the caffeine reducing liquid 6 cumulatively increase the content of theanine and the like.

  Since the caffeine reducing liquid 6 penetrates into the raw material 4 during extraction in a state containing components such as theanine, the mixture of the raw material residue and the caffeine reducing liquid 6 after taking out from the extraction tank 11a is leached from the raw material 2. It retains the components such as theanine. The decaffeinated matcha tea produced using this mixture retains the ingredients derived from the raw material 2. Moreover, when the manufacturing method shown in FIG. 3 is performed using the decaffeination processing apparatus 1a, a mixture of the raw material residue and the caffeine reducing liquid 6 can be obtained without performing the mixing step, so that the mixing step can be omitted. it can.

  When the liquid circulation process is completed, the raw material extract 5 and the caffeine reducing liquid 6 are present in the decaffeination processing apparatus 1a. Here, when the unextracted raw material 2 is newly prepared and the production method shown in FIG. 3 is subsequently performed, the raw material extract 5 and the caffeine reducing liquid 6 in the decaffeination processing apparatus 1a are utilized. Can do.

  When the raw material extract 5 and the caffeine reducing liquid 6 in the decaffeination treatment apparatus 1a are utilized and the newly prepared raw material 2 is placed in the extraction tank 11a and the liquid circulation process is repeated, the raw material extract is obtained. 5 and the concentration of theanine contained in the caffeine reducing solution 6 are cumulatively increased. Eventually, the concentrations of theanine and the like contained in the raw material extract 5 and the caffeine reducing solution 6 reach equilibrium with the concentrations of theanine and the like contained in the raw material 2 and the raw material 4 during extraction. Thereby, since the mixture of the caffeine reduction liquid 6 containing raw material residue and theanine etc. in high concentration can be obtained in a liquid circulation process, the decaffeinated matcha tea to be produced is theanine, fragrance component, etc. derived from the raw material 2 Is held as it is.

  When using the raw material extract 5 and the caffeine reducing liquid 6 and repeating the operation of performing the liquid circulation process by putting the newly prepared raw material 2 into the extraction tank 11a, the cold water 3, the raw material extract 5 and the caffeine reducing liquid are used. 6 is preferably kept at 5 ° C. or lower. When kept at 5 ° C. or lower, propagation of miscellaneous bacteria can be suppressed while suppressing degradation of teaan-derived theanine and alteration of pigment components. For this reason, the remaining raw material extract 5 and caffeine reducing liquid 6 can be used repeatedly over a long period of time, and mass production of decaffeinated matcha is facilitated.

[Embodiment 4]
The decaffeinated green tea manufacturing method shown in FIG. 3 using the decaffeinated processing device 1b shown in FIG. 5 is described only in the configuration and the operational effects different from the manufacturing method using the decaffeinated processing device 1a shown in FIG. To do. The decaffeination processing apparatus 1b shown in FIG. 5 includes a precipitation tank 21 and a filter 32 as compared with the decaffeination processing apparatus 1a shown in FIG.

  As shown in FIG. 5, the precipitation tank 21 is provided below the extraction tank 11b. Further, the extraction tank 11b includes a tubular foot portion 15 extending in the vertical direction below the filter plate 14. The foot 15 penetrates the ceiling plate of the sedimentation tank 21 and extends to the middle of the sedimentation tank 21. A portion near the upper end portion of the inner wall surface of the sedimentation tank 21 communicates with the pipe 33. The pipe 33 communicates with the porous polymerization resin 31, and a filter 32 is provided in a portion of the pipe 33 between the precipitation tank 21 and the porous polymerization resin 31.

  If the manufacturing method shown in FIG. 3 is performed using the decaffeination processing apparatus 1b, an extraction process is performed in the extraction tank 11b, and the raw material extract 5 flows down from the filter plate 14 through the foot 15 to form a precipitation tank. 21. A certain amount of the raw material extract 5 is stored in the precipitation tank 21. When the raw material 2 flows out from the filtration bag 13, insoluble matter such as powdered green tea and tea tea debris is mixed into the raw material extract 5, but the insoluble matter having a large specific gravity is the inner bottom surface of the sedimentation tank 21. It deposits on and becomes the precipitate 22. When the valve 24 of the pipe 25 communicating with the inner bottom surface of the precipitation tank 21 is opened, the precipitate 22 can be discharged from the precipitation tank 21.

  In addition, when contaminants having a small specific gravity are mixed in the raw material extract 5, the contaminants become floating substances 23 in the vicinity of the water surface of the raw material extract 5 stored in the precipitation tank 21. An overflow overflow 28 is provided at the upper end of the inner wall surface of the sedimentation tank 21, and the floating material 23 flows into the overflow overflow 28 when the raw material extract 5 is excessively stored in the precipitation tank 21. To do. Here, when the valve 26 of the pipe 27 communicating with the overflow overflow 28 is opened, the suspended matter 23 can be discharged from the sedimentation tank 21.

  The raw material extract 5 stored in the sedimentation tank 21 flows through the pipe 33 and contacts the porous polymerization resin 31, but passes through the filter 32 before contacting the porous polymerization resin 21. The raw material extract 5 flowing in the pipe 33 contains fine fibers derived from the tea leaves, but the fine fibers are scraped when the raw extract 5 passes through the filter 32. . Even if the matcha that has flowed out of the filter bag 13 flows into the pipe 33, the matcha is also scraped off by the filter 32. The filter 32 prevents fine fibers or green tea from coming into contact with the porous polymer resin 31.

  When the decaffeination processing apparatus 1 b is used, insoluble matters and the like contained in the raw material extract 5 are blocked by the precipitation tank 21 and the filter 32 before reaching the porous polymer resin 31. For this reason, the frequency with which the porous polymer resin 31 is clogged with insoluble matter or the like can be reduced. Moreover, since the decaffeination processing apparatus 1b is provided with the precipitation tank 21, compared with the case where a filter is used in order to protect porous polymer resin with the manufacturing method shown in FIG. 1, the frequency with which the filter 32 is clogged is lowered. be able to. Since the decaffeination processing apparatus 1b can keep the frequency of washing the porous polymer resin 31 and replacing the filter 32 low, the decaffeination processing apparatus 1b can operate continuously for a long time, and can further mass-produce decaffeinated green tea.

[Embodiment 5]
The manufacturing method shown in FIG. 3 using the decaffeination processing apparatus 1c shown in FIG. 6 will be described only in the configuration and the operational effects different from the manufacturing method using the decaffeination processing apparatus 1a shown in FIG. The decaffeination processing apparatus 1c shown in FIG. 6 includes a filtration container 12 in the extraction tank 11c as compared with the decaffeination processing apparatus 1a shown in FIG. 4 described above.

  The filtration container 12 is a container for filtering the raw material 2 or the raw material 4 during extraction, and placed on the filter plate 14 of the extraction tank 11c with the raw material 2 put in the container 12, The container 12 can be removed from the extraction tank 11c in a state where the mixture of the raw material residue and the caffeine reducing liquid 6 is put. When the filtration container 12 is placed on the filtration plate 14, the filtration container 12 covers the upper surface of the filtration plate 14 and the portion of the inner wall surface of the extraction tank 11 c above the filtration plate 14. Dimensions.

  When the prepared raw material does not contain matcha, the filtration container 12 has a structure in which a mesh member for filtration is attached between the frames of the frame member, or a filter cloth for food between the frames of the frame member The thing of the structure which attached is mentioned. When the prepared raw material contains matcha, the filtration container 12 includes a fine cloth such as flannel, a filter paper, a paper filter used when brewing coffee, a pulp filter, etc. between the frame members. The thing of the structure which attached the paper for filtration is mentioned. In this case, the cloth or paper attached to the filtration container 12 may have a structure in which a plurality of cloths or papers are stacked. The filtration container 12 is preferably provided with a handle in order to facilitate its transfer.

  Compared with the filtration bag 13 of the decaffeination treatment apparatus 1a shown in FIG. 4 described above, the filtration container 12 of the decaffeination treatment apparatus 1c shown in FIG. Can be put inside. When the filtration container 12 is provided, the labor of transferring the raw material 2 and the raw material residue can be reduced. In addition, while performing the liquid circulation process using the decaffeination processing apparatus 1c, a part of the raw material 4 during extraction is taken out from the opening of the filtration container 12, or the additional raw material 2 is reduced in caffeine. The amount of the raw material 2 and the raw material 4 during extraction can be adjusted as necessary during the extraction process, such as being immersed in the liquid 6.

[Testing method for color tone deterioration of powder such as raw material residue]
100 g tailored tea leaves were prepared as raw materials, and 1 L of distilled water at 5 ° C. was prepared as cold water. The raw material was packed in a flannel filter bag, cold water was poured into a beaker, and the raw material was soaked in cold water and extracted in a cold room at 5 ° C. The beaker was capped during extraction.

  When 30 minutes had elapsed from the start of extraction, the raw material together with the bag was taken out of the cold water and drained to obtain a raw material during extraction. About 5 g of the raw material in the middle of extraction was collected, and the remaining raw material in the middle of extraction that was not collected was immersed in the same cold water together with the bag and extracted again. Similarly, when 5 hours, 20 hours, 28 hours, 44 hours, and 52 hours had elapsed from the start of extraction, extraction was continued while collecting about 5 g of raw material during extraction. When 68 hours elapsed, the raw material was extracted from the cold water together with the bag and drained to obtain a raw material residue. About 5 g of the raw material residue was collected.

  Each collected raw material and raw material residue were freeze-dried with a freeze dryer (Tokyo Rika Kikai Co., Ltd., FDU-810) to remove moisture, and pulverized with an electric stone mill (Panasonic Corporation, EU-6820P). In the course of each extraction, a dry powder of raw material or raw material residue was obtained. Further, for comparison, 5 g of freshly prepared tea leaves were prepared as raw materials, and the raw materials without being subjected to extraction treatment were freeze-dried and pulverized to prepare dry tea powder.

  5 parts by weight of distilled water is added to 1 part by weight of each dry powder to moisten the powder, and moistened with a color difference meter (manufactured by Nippon Denshoku Industries Co., Ltd .: ZE-2000) according to JIS Z 8729. The color tone of the obtained powder was measured, and a value serving as an index of greenness in the Lab color system was recorded.

[Test results and discussion on color tone deterioration of powder such as raw material residue]
The test results are shown in Table 1. The a value indicates that the green color tone is strong when the negative value is large, and the red color tone is strong when the positive value is large.

  As shown in Table 1, the a value of the raw material powder not subjected to the extraction treatment was -12.0. On the other hand, the a value of the raw material powder extracted from the raw material with cold water at 5 ° C. increased with the passage of time from −11.0 at the time of 30 minutes to the raw material residue at the time of 68 hours. The powder remained at -9.7. It has been shown that when the raw tea leaves are extracted with cold water at 5 ° C., the speed at which the color tone of the raw material deteriorates from green to red is extremely slow. Moreover, it was shown that even if the tailored tea leaves were extracted with cold water at 5 ° C. for 68 hours to produce matcha, matcha with little deterioration in the original color tone of matcha could be produced. The same experimental results were obtained when matcha was used as a raw material.

[Test method for color deterioration of decaffeinated green tea]
5 g tailored tea leaves were prepared as raw materials, and 150 ml of 4 ° C. distilled water was prepared as cold water. The raw material was packed in a flannel filter bag, cold water was poured into a beaker, and the raw material was soaked in cold water and extracted in a cold room at 4 ° C. When 72 hours had elapsed from the start of extraction, the raw material together with the bag was taken out of the cold water and drained to obtain a raw material residue. The cold water left in the beaker was used as the raw material extract.

  A raw material extract is passed through a column packed with a porous polymer resin (Amberlite FPX66, manufactured by Dow Chemical Co., Ltd.), and the raw material extract is brought into contact with the porous polymer resin to adsorb caffeine to obtain a caffeine reducing solution. It was. The raw material residue and the caffeine reducing solution were separately lyophilized with the above-described freeze dryer to remove moisture, and each dried product was obtained. The dried material residue was pulverized with the above-mentioned electric stone mill to obtain a dried powder of the material residue. The dried product of the caffeine reducing liquid and the dried powder of the raw material residue were mixed with a teaspoon so as to be almost uniform to obtain a sample of decaffeinated matcha tea of Example 1.

  In addition, a sample of decaffeinated green tea of Example 2 was produced under the same conditions as Example 1 except that the extraction time was 30 minutes. Furthermore, the same raw material as in Example 1 was prepared, and this raw material was pulverized as it was with an electric stone mill to obtain a green tea sample of Comparative Example 1.

  For the samples of Examples 1 and 2 and Comparative Example 1, the a value was measured by the method described above. In addition, the samples of Examples 1 and 2 and Comparative Example 1 were subjected to high performance liquid chromatography, and the caffeine content and theanine content of each sample were calculated using a calibration curve prepared with a sample. Further, assuming that the content of each component of the sample of Comparative Example 1 was a retention rate of 100%, the retention rate of caffeine and the retention rate of theanine were calculated from the content of each component of the samples of Examples 1 and 2. .

The test results are shown in Table 2.

  As shown in Table 2, it was -9.4 in Example 1 and -11.1 in Example 1 with respect to the a value of -12.0 in Comparative Example 1. Since the difference in the a value between Comparative Example 1 and Examples 1 and 2 is small, Examples 1 and 2 have less deterioration in color tone so as to meet the quality control standards of the matcha tea manufacturer. In particular, from the results of Example 1, even if it is extracted over 72 hours, if the raw material is extracted with cold water at 4 ° C. and the raw material extract is kept at 4 ° C., decaffeinated matcha with little deterioration in color tone is produced. It was shown that it can be done.

  The content of caffeine in Comparative Example 1 was 3.1% by weight, whereas Example 1 was 0.4% by weight, and Example 2 was 1.2% by weight. From the results of Example 1, it was shown that if extraction was performed over 72 hours, the retention rate of caffeine was 12.9%, and the content of caffeine could be sufficiently reduced. From the results of Comparative Example 2, it is possible to reduce the content of caffeine to a retention rate of 38.7% by leaching most of the caffeine contained in the raw material into cold water even if the extraction time is 30 minutes. Indicated.

  The content of theanine in Comparative Example 1 was 2.0% by weight, whereas in Examples 1 and 2, it was 1.8% by weight. From the test results of Examples 1 and 2, when the raw material was extracted with cold water at 4 ° C., and the respective dried products obtained by freeze-drying the raw material residue and the caffeine reducing liquid were mixed, about 90% of the theanine derived from the raw material was mixed. It has been shown that decaffeinated matcha tea can be produced.

[Testing method for decaffeinated matcha color tone, shaded matcha shade and flavor]
Prepare distilled water at about 0 ° C as cold water, extract the raw material with cold water for 5 hours in the 0 ° C refrigerated room, and bring the raw material extract into contact with the porous polymer resin in the 0 ° C refrigerated room. A decaffeinated matcha tea of Example 3 was produced under the same conditions as in Example 1 except that it was adsorbed. During the production, it was not observed that the cold water, the raw material extract and the caffeine reducing solution were solidified.

  The a value of Example 3 was measured by the method described above. Moreover, the green tea sample of Comparative Example 1 was manufactured. Matcha was turned on using the samples of Example 3 and Comparative Example 1, and the shades of the matcha were visually compared by 10 panelists. After that, 10 panelists drank and compared the flavored green tea and compared the flavors.

[Test results and consideration of decaffeinated matcha color tone, shaded matcha shade and flavor]
Table 3 shows the test results for the color tones of Example 1 and Comparative Example 1.

  As shown in Table 3, the value of a in Example 3 was -11.2 compared to the value a of -12.0 in Comparative Example 1. Further, Example 3 and Comparative Example 1 had almost the same color tone as it was difficult to distinguish the difference visually.

  The matcha green tea used in Example 3 and the green tea used in Comparative Example 1 are almost the same in color, so the panelists evaluated that 10 panelists were indistinguishable visually. On the other hand, when the matcha green tea used in Example 3 was compared with the green tea tea prepared using Comparative Example 1, the three panelists evaluated that the difference in flavor was not recognized, but the seven panelists Evaluated that the matcha tea used in Example 3 had a mellow and preferred flavor.

  The reason why the three panelists could not recognize the difference in flavor was that the raw material was extracted with cold water at about 0 ° C. and freeze-dried, so that theanine was maintained at 70% or more and the scent component was also retained. it is conceivable that. Seven panelists evaluated that the matcha tea that was turned on using Example 3 had a mellow flavor because the content of caffeine that had a bitter taste was the matcha that was turned on using Example 3. This is probably because the taste of theanine is more pronounced. Alternatively, when the decaffeinated matcha tea of Example 3 is produced, the content of catechins exhibiting astringency due to the porous polymer resin has been reduced, so that the umami taste may have been enhanced.

  The decaffeinated matcha according to the present invention has little deterioration of the original flavor and color tone of matcha, has a sufficiently reduced caffeine content, and can be used as a matcha or as a food ingredient. . The decaffeinated matcha according to the present invention is not limited to people who want to avoid the intake of caffeine, but can provide people with the same color and flavor as matcha that has not been decaffeinated. Furthermore, the above-mentioned decaffeinated matcha can be obtained by the method for producing decaffeinated matcha according to the present invention. Moreover, the decaffeinated processing apparatus according to the present invention can efficiently mass-produce the aforementioned decaffeinated matcha tea when used in carrying out the aforementioned production method.

DESCRIPTION OF SYMBOLS 1 Decaffeination processing apparatus 2 Raw material 3 Cold water 4 Extraction raw material 5 Raw material extract 6 Caffeine reduction liquid 11 Extraction tank 31 Porous polymer resin 41 Liquid feeding means

Claims (7)

Preparing a raw material selected from the group consisting of tailored tea leaves, matcha tea and mixtures thereof;
Extracting the raw material with cold water to obtain a raw material extract and a raw material or raw material residue during extraction;
A decaffeination step of contacting the raw material extract with a porous polymer resin to adsorb caffeine to obtain a caffeine-reducing liquid;
Freeze-drying the raw material residue and the caffeine reducing solution to obtain a dried product of the raw material residue and a dried product of the caffeine reducing solution,
For producing decaffeinated matcha tea.   The method for producing decaffeinated matcha according to claim 1, wherein the cold water is 10 ° C or lower.   The method for producing decaffeinated matcha according to claim 1 or 2, wherein the drying step freeze-drys the mixture of the raw material residue and the caffeine reducing liquid. An extraction continuation step of sending the caffeine reducing solution to the raw material during extraction, extracting the raw material during extraction with the caffeine reducing solution, and obtaining the raw material extract,
The decaffeinated matcha tea according to any one of claims 1 to 3, further comprising a liquid circulation step in which the extraction continuation step and the decaffeination step are repeated to obtain a mixture of the raw material residue and the caffeine reduction solution. Production method.   Decaffeinated green tea obtained by the production method according to any one of claims 1 to 4. An extraction tank for extracting raw materials selected from the group consisting of tailored leaves of green tea, matcha tea and mixtures thereof with cold water or caffeine reducing liquid, and obtaining raw material extracts and raw materials or raw material residues during extraction;
A porous polymerization resin that contacts the raw material extract and adsorbs caffeine to obtain the caffeine-reducing liquid;
A liquid feeding means for sending the caffeine reducing liquid to the extraction tank;
A decaffeination processing apparatus comprising: A sedimentation tank provided below the extraction tank;
A filter provided so that the raw material extract passes before contacting the porous polymer resin;
A decaffeination treatment apparatus according to claim 6.

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