JP6504784B2 - Decaffeinated green tea, method for producing the same, and decaffeinated processing apparatus - Google Patents

Description

  TECHNICAL FIELD The present invention relates to decaffeinated green tea with little deterioration in flavor and color inherent to matcha, a method for producing the same, and a decaffeination treatment apparatus.

  The high-quality green tea has a strong flavor, weak astringency and bitterness, has a slightly sweet smell, and maintains a bright green tint. The reason for the strong taste is that Matcha tea contains a large amount of theanine. Matcha is also rich in caffeine.

  In the West, decaffeinated coffee has been manufactured for those who want to avoid caffeine consumption. During production, methods such as an organic solvent extraction method, a Swiss-type water extraction method, and a supercritical carbon dioxide extraction method have been adopted for decaffeination treatment. It is conceivable to produce decaffeinated green tea by applying these methods.

  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 Sanitation Law, and furthermore, the smell of the organic solvent impairs the subtle aroma of Matcha. . In the supercritical carbon dioxide extraction method, Matcha is discolored because pigment components are extracted and removed.

  On the other hand, a method for producing a solid tea with a reduced content of caffeine has been developed without using the organic solvent extraction method, the Swiss water extraction method, or the supercritical carbon dioxide extraction method (patent document See 1). According to the method described in Patent Document 1, powdered green tea is prepared as a raw material, the raw material is extracted with water or ethanol, heat treatment is performed, caffeine leached from the raw material is distilled away with water or ethanol, decaffeination Matcha can be produced.

JP 2008-212024 A

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

  Then, an object of this invention is to provide the decaffeinated green tea with little deterioration of the flavor and color tone of a matcha green tea, and its manufacturing method. Furthermore, another object of the present invention is to provide a decaffeination treatment apparatus used in the method for producing decaffeinated green tea described above.

  In order to achieve the above object, the process for producing decaffeinated green tea according to the present invention comprises the steps of preparing a raw material selected from the group consisting of green tea leaves, matcha green tea and mixtures thereof, and using cold water as the raw material Extraction step to obtain a raw material extract, and a raw material extract or raw material residue during extraction, and contacting the raw material extract with a porous polymer resin to adsorb caffeine to obtain a caffeine-reduced liquid It is comprised so that a drying process of freeze-drying the said raw material residue and the said caffeine reduction liquid, and obtaining the dried material of the said raw material residue and the dried product of the said caffeine reduction liquid will be carried out.

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

  The drying step is configured to lyophilize a mixture of the raw material residue and the caffeine reduction liquid.

  The caffeine reduction liquid is sent to the extraction intermediate raw material, and the extraction intermediate raw material is extracted with the caffeine reduction liquid to obtain an extraction raw material extraction step, the extraction continuation step, and the decaffeination The process is repeated, and it is comprised so that 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 green tea according to the present invention is configured to be obtained by the method for producing decaffeinated green tea.

  Furthermore, the decaffeination treatment apparatus according to the present invention extracts the raw material selected from the group consisting of green tea tanning leaves, matcha tea and a mixture thereof with cold water or caffeine reducing liquid, and extracts the raw material extraction liquid, and An extraction tank for obtaining a raw material or a raw material residue, a porous polymer resin for obtaining caffeine-reduced liquid by contacting with the raw material extract and adsorbing caffeine, and sending the caffeine-reduced liquid to the extraction tank And liquid means.

  Moreover, it comprises so that the sedimentation tank provided below the said extraction tank and the filter provided so that the said raw material extract could pass before contacting the said porous polymeric resin.

  In the method for producing decaffeinated green tea according to the present invention having the above-described configuration, caffeine contained in the tailored leaves of green tea as raw material and caffeine contained in the green tea is removed by adsorbing to the porous polymer resin after leaching in cold water . For this reason, decaffeinated green tea has a reduced content of caffeine derived from raw materials. Here, decaffeination refers to a state in which caffeine is partially removed and the caffeine content is reduced.

  Moreover, in the method for producing decaffeinated green tea according to the present invention, the raw material is extracted with cold water, and the raw material residue and the caffeine-reduced liquid are freeze-dried, so that the degradation of theanine and the reduction of the scent component can be suppressed. Moreover, in order to produce decaffeinated green tea using both the raw material residue and the caffeine reduction liquid, not only the ingredients of the raw material residue but also the components transferred to the caffeine reduction liquid are used in the decaffeinated green tea. It has been collected. For this reason, decaffeinated green tea has the theanine and aroma components derived from the raw material preserved.

  In the method for producing decaffeinated green tea according to the present invention, deterioration 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 solution are dried by lyophilization, degeneration of the pigment component can be avoided during the drying. For this reason, decaffeinated green tea maintains a bright green color tone.

  Therefore, according to the present invention, decaffeinated green tea with less deterioration of the original flavor and color tone of green tea and a method for producing the same are provided. Furthermore, according to the present invention, there is provided a decaffeination treatment apparatus for use in a method of producing decaffeinated green tea.

Flow chart of the method for producing decaffeinated green tea according to the first embodiment Flow chart of the method for producing decaffeinated green tea according to the second embodiment Flow chart of the method for producing decaffeinated green tea according to the third embodiment The cross-sectional end view of the said apparatus which represents one form of the decaffeination processing apparatus used with the manufacturing method of the decaffeinated green tea which concerns on Embodiment 3. The cross-sectional end view of the said apparatus which represents the other form of the decaffeination processing apparatus used with the manufacturing method of the decaffeinated green tea which concerns on Embodiment 4. The cross-sectional end view of the said apparatus which represents the other form of the decaffeination processing apparatus used with the manufacturing method of the decaffeinated green tea which concerns on Embodiment 5

Embodiment 1
The method for producing decaffeinated green tea shown in FIG. 1 includes the steps of preparing the raw material, the extraction step, the decaffeination step, and the drying step.

  In the step of preparing the raw material, any one of a green tea leaf, green tea, and a mixture of green leaf and green tea leaves is prepared as a raw material for decaffeinated green tea. Depending on the degree of processing, navy green tea is in the stage of becoming dark brown indigo tea and in the stage in which it is in the form of tailored leaves of navy brown tea. Tea leaves are plucked from tea trees cultivated dark from 2-3 weeks before plucking, steamed fresh tea leaves are steamed, and the steamed leaves are dried without drying. The tailoring leaves of the persimmon tea are obtained by cutting the rough tea of the persimmon tea, separating the stems and veins, and selecting the mesophyll from among the cut products. For example, the dimension of one side of the tea leaf of Zen tea is about 3 to 5 mm.

  Raw material green tea is a powder obtained by grinding the green tea leaves with a mortar, and has not been decaffeinated yet. As a millet used when preparing green tea, although an electric milled mill is mentioned, in order to suppress the heat denaturation of theanine and a fragrant ingredient, the millstone for handmade is preferable. In addition, it is preferable that green tea used as the raw material is one obtained by grinding the leaves of green tea with a mill and then further removing the contaminants by a sieve. The particle size of the raw material green tea is, for example, about 1 to 20 μm.

  In the case of preparing a mixture of green tea tanning leaves and green tea as raw materials, there are no particular limitations on the mixing ratio between green tanning leaves and green tea.

  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 detail. In the extraction step, the raw material is placed in a filtration bag, the bag and the raw material are immersed in cold water, 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 less, most of the caffeine contained in the raw material is leached into the cold water if the raw material is immersed in the cold water for 30 minutes or more.

  However, when the cold water in contact with the raw material coagulates into ice, caffeine leaching does not proceed. When the water temperature is higher than 15 ° C., the color tone of the raw material and the raw material extract tends to deteriorate during extraction, and thus there is a possibility that the decaffeinated green tea will be a color tone deteriorated. If the temperature is higher than 15 ° C., bacteria will be easily propagated to the raw material and the like.

  The water temperature of the cold water is preferably 10 ° C. or less. When the temperature is 10 ° C. or less, the deterioration of the color tone of the raw material and the raw material extract becomes extremely slow at the time of extraction, so that the decaffeinated green tea is the one in which the deterioration of the color tone is particularly suppressed. Moreover, it can suppress that various germs breed in a raw material etc. as it is 10 degrees C or less.

  The water temperature of the cold water is more preferably 5 ° C. or less. When the temperature is 5 ° C. or less, the deterioration of the color tone of the raw material or the raw material extract during the extraction is extremely delayed. For example, even if it takes 72 hours to extract the raw material with cold water of 5 ° C. or less, it is possible to produce decaffeinated green tea whose color tone deterioration is suppressed so that it can not be distinguished from matcha green tea which has not been decaffeinated. can do. Moreover, it can further suppress that a germ proliferates to a raw material etc. as it is 5 degrees C or less.

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

  When Matcha is included in the prepared raw material, it is better to use a filter bag made of a fine cloth or paper, as compared to the case where Matcha is not contained in the raw material. As such a filtration bag, for example, a filtration bag composed of flannel, a filter paper, a paper filter used when making coffee, a filtration bag composed of filtration paper such as a pulp filter can be mentioned. The filtration bag may have a structure in which a plurality of fine cloths or papers are stacked. Use of a filtration bag made of fine cloth or paper can prevent the raw green tea from flowing out of the filtration bag during extraction. If the outflow of the green tea is prevented, it is possible to prevent the porous polymeric resin from being clogged by the outflowed green tea in the subsequent decaffeination step.

  In the first extraction step, cold water is stored in the first extraction tank, the bag and the raw material are immersed in the cold water, and the raw material is extracted with cold water. After a certain time, the bag and the raw material are taken out of the cold water, and the raw material is drained. The raw material after being taken out of the cold water has caffeine which has not been able to leach out into the cold water. For this reason, the raw material removed from 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 bag and the raw material during the extraction are immersed in the cold water, and the raw material during the extraction is extracted with the cold water. After a certain period of time, the bag and the raw material during extraction are taken out from the cold water, and the raw material is drained during the extraction. After extraction from cold water, caffeine which has not been able to leach out into cold water remains in the raw material during extraction. For this reason, the raw material on the way of extraction extracted from the cold water in the second extraction step and drained is also handled as the raw material on the way of extraction.

  In the third extraction step, cold water is stored in the third extraction tank, and the raw material on the way of the extraction which has been subjected to the second extraction step is soaked with the bag in the cold water, and the raw material on the way is extracted with cold water. After a certain period of time, the bag and the raw material during extraction are taken out from the cold water, and the raw material is drained during the extraction. In the third extraction step, caffeine is further leached from the raw material during extraction, so the raw material during extraction has a sufficiently reduced caffeine content compared to the raw material before extraction. For this reason, the raw material on the way of extraction taken out of the cold water and drained in the third extraction step is handled as a raw material residue.

  After completion 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 used as raw materials or in the middle of extraction. Cold water containing ingredients such as caffeine leached from the raw material is left. These cold waters are mixed, and the obtained mixed liquid is handled as a raw material extract. In the extraction step of the manufacturing method shown in FIG. 1, the raw material residue and the raw material extract are obtained through the first extraction step, the second extraction step, and the third extraction step.

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

  In the extraction step, for example, 30 parts by weight of cold water is used in total by using 10 parts by weight of cold water in each of the first extraction step, the second extraction step, and the third extraction step with respect to 1 part by weight of the raw material. The extraction efficiency of caffeine depends on the difference between the concentration of caffeine contained in the raw material or the raw material during extraction and the concentration of caffeine contained in cold water. It is better to extract three times using 10 parts by weight of cold water in each of the first extraction step, the second extraction step, and the third extraction step, rather than extracting in one time using 30 parts by weight of cold water, The caffeine extraction efficiency is good because there are three opportunities to be extracted with cold water that does not contain caffeine at all.

  In the extraction step of the manufacturing method shown in FIG. 1, although the three steps of the first extraction step, the second extraction step, and the third extraction step are performed, the extraction step is not limited to the three steps. The extraction step may further include a multistage step, for example, a fourth extraction step or a fifth extraction step.

  Ice and cold water may be added to the extraction tank as needed during extraction. The length of 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, it is difficult to sufficiently leach out caffeine contained in the raw material because the extraction time is too short. If it is longer than 72 hours, there is a possibility that various bacteria may be propagated to the raw material and the like.

  When the prepared raw material is green tea, the extraction efficiency of caffeine in the extraction process is better than when the raw material is a green tea tailored leaf. It is because Matcha has a larger surface area per unit weight than Matcha 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 to the case where the raw material is pure tea leaves.

  In the decaffeination step, the raw material extract is brought into contact with the porous polymer resin. Thus, 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-reduced liquid in which the content of caffeine is reduced.

  When powdered tea is not contained in the prepared raw material, the method to which a raw material extract liquid is made to contact with porous polymeric resin is not specifically limited. For example, there is a method of preparing a column packed with a porous polymerization resin, and letting the raw material extract flow and pass through the column. Under the present circumstances, the flow velocity of the raw material extract which passes through the inside of a column is suitably set so that the caffeine contained in a raw material extract may adsorb | suck with a porous polymeric resin efficiently.

  In the case where the prepared raw material contains matcha tea, it is desirable to protect the porous polymer resin so that the matcha tea does not come in contact when matcha tea has flowed out of the filtration bag. For this reason, when powdered tea is contained in the prepared raw material, it is preferable to pass the raw material extract through the filter and to bring the raw material extract having passed through the filter into contact with the porous polymer resin. Even if the raw material extract contains powdered green tea that has flowed out, or fine fibers derived from the tanning leaves of mochi tea, it is possible to avoid clogging of the porous polymer resin because it is removed by the filter. .

  As a filter for protecting the porous polymer resin, filter paper, paper filter used for brewing coffee, paper filter for filtration such as pulp filter, fine cloth filter such as flannel, synthetic resin A filter, a filter made of glass fiber, etc. may be mentioned. For example, Matcha tea can be removed through filter paper or paper filters, so if a filter with a filtration density similar to that of the filter paper or paper filter is used, clogging of the porous polymer resin can be avoided.

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

  Although porous polymeric resin mainly adsorbs caffeine, it uses the thing of the material which is hard to adsorb theanine. Examples of the polymerization resin constituting the porous polymerization resin include styrene-based or acrylic-based crosslinked polymers, copolymers of styrene and divinylbenzene, methacrylic acid ester-based resins, and polycondensation polymers of methacrylic acid and diols. 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, for example, Amberlite XAD such as Diaion HP series, Sepabeads SP series (above, manufactured by Mitsubishi Chemical Corporation), Amberlite XAD-4, Amberlite FPX66, Amberlite XAD-1180N, etc. Synthetic adsorbents such as Series (manufactured by Dow Chemical Co., Ltd.) can be used.

  It is more preferable to use a porous polymer resin that selectively adsorbs caffeine and is not limited to theanine but is made of a material that hardly adsorbs components other than caffeine contained in the raw material extract. Specific examples of such porous polymer resins include synthetic adsorbents such as Amberlite FPX 66 (manufactured by Dow Chemical Co.). When using a porous polymer resin that selectively adsorbs caffeine and hardly adsorbs components other than caffeine, the components that have leached out from the materials other than caffeine are not removed, so the original flavor and color of matcha It is possible to produce decaffeinated green tea with particularly low degradation of

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

  It is desirable that the extraction step and the decaffeination step described above be performed by providing the extraction tank and the porous polymerization resin in a refrigerator compartment higher than 0 ° C. and 15 ° C. or less. Temperature control is easier if the extraction step or the decaffeination step is performed in the cold storage room than cooling using a cooling device. 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 more than 0 ° C. and 10 ° C. or less, still more preferably more than 0 ° C. and 5 ° C. or less.

  In the drying step, using a lyophilizer, each of the raw material residue and the caffeine reducing solution is separately freeze-dried to remove water. 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 reduced liquid is obtained from the caffeine reduced solution.

  When the prepared raw material contains a tailored leaf of mulberry tea, after the drying step, the dried product of the raw material residue is pulverized using a millet to carry out a pulverizing step of obtaining a dried powder of the raw material residue. As a millet used in the drying step, an electric milled mill can be mentioned, but in order to suppress thermal denaturation of theanine or an aroma component, a milled millet for manual grinding is more preferably mentioned. When the raw material prepared is only green tea, the dried product of the raw material residue obtained in the drying step is already a dry powder, and therefore the grinding step can be omitted. After the pulverizing step, a mixing step of mixing the dried powder of the raw material residue and the dried product of the caffeine-reduced solution is performed using a stirrer, a spatula and the like. Treat the powder obtained in the mixing step as decaffeinated green tea.

  As a method of producing decaffeinated green tea, a method of extracting raw materials with ethanol is also considered. However, even if freeze-dried, it is difficult to completely remove the ethanol that has permeated the raw material residue, so that the decaffeinated green tea will contain a small amount of ethanol. In this case, if the green tea is turned on with the use of decaffeinated green tea, the ethanol warmed with hot water is vaporized, and the smell of ethanol impairs the faint smell of the green tea.

  As a method for producing decaffeinated green tea, a method is conceivable 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. However, when the raw material is extracted with hot water or acidic warm water, theanine may be decomposed or the pigment component may be degraded. Although it is conceivable to add ascorbic acid to hot water or warm water in order to suppress deterioration of the components, if the amount added is large, the original flavor of matcha is lost.

  On the other hand, when the above-mentioned 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-mentioned decaffeination step is performed, the caffeine transferred to the raw material extract is adsorbed to the porous polymer resin. For this reason, a raw material extract becomes caffeine reduction liquid in which the content of caffeine is selectively reduced. The decaffeinated green tea manufactured using both the raw material residue and the caffeine reducing solution is manufactured on the basis satisfying the Food Sanitation Law, and the content of caffeine derived from the raw material is reduced.

  In addition, since the raw material is extracted with cold water in the extraction step and the raw material residue and the caffeine-reduced liquid are lyophilized in the drying step, the degradation of theanine and the reduction of the odor component can be suppressed. Moreover, in order to produce decaffeinated green tea using not only the raw material residue but also the caffeine reduction liquid, the decaffeinated green tea is not only a component of the raw material residue but also theanine which has been transferred to the caffeine reduction liquid Aroma components and components such as potassium are recovered. Decaffeinated green tea retains the theanine and aroma components derived from the raw materials.

  There is a phenomenon that the color tone of the raw material and the extract of the raw material is deteriorated from green to red when the prepared leaves of green tea and matcha green tea are in contact with water. This phenomenon was suppressed by extracting the raw material with cold water in the extraction step. In addition, since the raw material residue and the caffeine reduction solution are dried by lyophilization in the drying step, the pigment component is prevented from degenerating during the drying. Decaffeinated green tea retains a vivid green color tone.

  Therefore, according to the manufacturing method shown in FIG. 1, decaffeinated green tea with less deterioration of the original flavor and color tone of green tea can be manufactured.

  If the content of theanine in decaffeinated green tea is maintained at 70% or more compared to the content of theanine in green tea that has not been decaffeinated, adding hot water to each of the green tea and adding the green tea to the matcha Even when compared with drinking, it is difficult to recognize that decaffeinated green tea reduces umami ingredients. For example, when the raw material is extracted with cold water at 15 ° C. for 30 minutes in the extraction step, the decaffeinated green tea obtained by the manufacturing method of FIG. 1 retains 80% or more of the content of theanine, 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 step, the decaffeinated green tea obtained by the production method of FIG. 1 is caffeine compared to the uncaffeinated green tea. The content is reduced to less than 40%, and it becomes difficult to visually recognize the difference in color tone. It is difficult to recognize that this decaffeinated green tea is degraded in its original flavor and color unless care is taken.

  When the raw material is extracted with cold water of 10 ° C. or less for 5 hours in the extraction step, the decaffeinated green tea obtained by the manufacturing method of FIG. 1 contains caffeine as compared to the uncaffeinated green tea. The amount is reduced to less than 20%, it is extremely difficult to visually recognize the difference in color tone, and the content of theanine is maintained at 80% or more. It is difficult for this decaffeinated green tea to be recognized as having degraded the original flavor and color of the green tea, even with care.

Second Embodiment
The method for producing decaffeinated green tea shown in FIG. 2 will be described only with respect to the configuration and effects different from the production method shown in FIG. 1 described above. Compared to the manufacturing method shown in FIG. 1, the manufacturing method shown in FIG. 2 is carried out in the order of the mixing step, the drying step and the grinding step after the decaffeination step.

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

  In the drying step, using a lyophilizer, the mixture of the raw material residue and the caffeine reduction liquid is freeze-dried to remove water, and a mixed dry matter of the raw material residue and the caffeine reduction liquid is obtained. The combined dry matter obtained after lyophilization is in a state in which the dry powder of the component leached from the raw material adheres to the surface of the dry matter of the raw material residue. When the raw material prepared is only green tea, the pulverizing step can be omitted, and the dried mixture obtained in the drying step may be handled as decaffeinated powdered green tea.

  In the case where the prepared raw material includes a tailored leaf of mulberry tea, in the grinding step, a mixture of the raw material residue and the caffeine reduction liquid is ground using a millet. Compared with the grinding process of the manufacturing method shown in FIG. 1, the dried product of the caffeine-reduced liquid is also ground and mixed in the dried powder of the raw material residue in the grinding process of the manufacturing method shown in FIG. The powder obtained by grinding with a mortar is handled as decaffeinated green tea.

  In the mixing process of the manufacturing method shown in FIG. 2, a part of caffeine reduction liquid permeates into a raw material residue, and becomes integral. In the drying step of the manufacturing method shown in FIG. 2, the caffeine-reduced liquid that has not permeated the raw material residue adheres to the dried material residual material upon lyophilization and becomes integrated. For this reason, when the raw material prepared is only green tea and the dried mixture obtained in the drying step is handled as decaffeinated green tea, the decaffeinated green tea is a combination of the components of the raw material residue and the components leached from the raw material It becomes what became.

  In addition, when the prepared raw material includes a tailored leaf of mochi tea, in the grinding process of the production method shown in FIG. The components of the residue and the components leached out of the raw material are uniformly mixed.

  Therefore, according to the production method shown in FIG. 2, it is possible to easily produce decaffeinated Matcha tea with little unevenness in the flavor, even when the prepared raw material is only Matcha Tea, or when the raw material contains Matched Leaves of Apricot Tea. Can.

Third Embodiment
With respect to the manufacturing method shown in FIG. 3 using the decaffeination processing apparatus 1a shown in FIG. 4, only the configuration and effects different from those of the manufacturing method shown in FIG. 2 will be described. The decaffeination treatment apparatus 1a shown in FIG. 4 is used to carry out the extraction step, the decaffeination step, the extraction continuation step, and the liquid circulation step in the manufacturing method shown in FIG.

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

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

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

  The filter bag 13 used in the decaffeination processor 1a preferably has a dimension capable of covering 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 filtration bag 13 may be sized so as to cover the entire 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 11 a.

  The raw material extract 5 flows down the lower side of the filter plate 14 and reaches the pipe 33. Since the porous polymeric resin 31 is provided in the pipe 33, the raw material extract 5 is in contact with the porous polymeric 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 is a caffeine reduction solution 6 in which the content of caffeine is reduced. For this reason, in the porous polymerization resin 31, the decaffeination step of obtaining the caffeine reduction liquid 6 by contacting the raw material extract 5 with the porous polymerization resin 31 and adsorbing caffeine can be performed.

  The caffeine reduction liquid 6 obtained in contact with the porous polymerization resin 31 reaches the liquid feed pump 42. The liquid feeding pump 42 feeds the caffeine-reduced liquid 6 to the shower unit 44 provided above the opened upper surface of the extraction tank 11 a through the pipe 43. The caffeine reduction liquid 6 sent to the shower unit 44 is discharged from the shower unit 44 into the storage tank 11 a. 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 reduction liquid 6 discharged into the extraction tank 11a contains components such as caffeine leached from the extraction raw material 4 when passing through the filtration bag 13 and the extraction raw material 4 and further passing through the filtration plate 14 It is a raw material extract 5. The raw material 4 is extracted with the caffeine reducing solution 6 to reduce the caffeine content during extraction, but there is still room for extracting caffeine. The raw material 4 during extraction after being extracted with the caffeine reduction liquid 6 is also handled as the raw material 4 during extraction. Therefore, the caffeine reduction liquid 6 is sent from the porous polymer resin 31 to the raw material 4 during extraction by the liquid transfer means 41 and the extraction tank 11a, and the raw material 4 is extracted with the caffeine reduction liquid 6 during extraction, An extraction continuation step can be performed to obtain 5.

  The raw material extract 5 obtained in the extraction continuing step flows down the lower side of the filter plate 14 and reaches the porous polymer resin 31 through the pipe 33. For this reason, the decaffeination step is performed again with the porous polymerization resin 31. The caffeine reduction liquid 6 obtained in the decaffeination step is sent to the inside of the extraction tank 11 a by the liquid feeding means 41, and thus becomes the raw material extract 5 again in the extraction continuing step. Thus, the content of caffeine contained in the raw material 4 during extraction can be sufficiently reduced by repeatedly performing the extraction continuing step and the decaffeination step. In addition, the caffeine reduction liquid 6 penetrates into the raw material 4 during the extraction while replacing the extracted components such as caffeine.

  After repeating the extraction continuation step and the decaffeination step, the entire extraction bag 4 is taken out of the extraction tank 11a together with the filter bag 13, and the raw material 4 in the middle of extraction without draining is handled as a mixture of the raw material residue and the caffeine reduction liquid 6. In addition, the extraction continuation step and the decaffeination step are repeated by the extraction tank 11a, the porous polymerization resin 31, and the liquid feeding means 41 to perform a liquid circulation step to obtain a mixture of the raw material residue and the caffeine reduction liquid. it can.

  The mixture of the raw material residue obtained in the liquid circulation step and the caffeine reduction liquid 6 is removed from the filter bag 13 and freeze-dried by a lyophilizer. The lyophilizer can lyophilize the mixture of the raw material residue and the caffeine reduction liquid 6 to obtain a drying step of obtaining a mixture of the dried material residue and the dry substance of the caffeine reduction liquid 6. Next, a grinding process can be performed by grinding the mixture of the dried material residue and the dried product of caffeine reduction liquid 6 with a millet to obtain decaffeinated green tea.

  When the production method shown in FIG. 3 is performed using the decaffeination treatment apparatus 1a, caffeine contained in the raw material 4 during extraction is repeatedly leached and caffeine transferred to the raw material extract 5 is a porous polymer resin 31. Is repeatedly removed by Therefore, when the liquid circulation process is performed for a long time, the caffeine content of the caffeine reduction liquid 6 is gradually reduced. In the liquid circulation process, caffeine continues to be efficiently extracted 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 reduction 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 even better than when the manufacturing method shown in FIGS. 1 and 2 described above is performed. Therefore, for example, when the extraction step, the decaffeination step, the extraction continuation step, and the liquid circulation step are performed over a total of 3 hours, decaffeinated green tea with a content of caffeine reduced by 80% or more can be produced. it can. In addition, since caffeine extraction efficiency is good, a small amount of cold water 3 is required, and the caffeine reduction solution 6 is also small, so that the processing time of the lyophilization in the drying step can be shortened to reduce the cost.

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

  Since the caffeine reduction liquid 6 penetrates into the raw material 4 during extraction while containing components such as theanine, the mixture of the raw material residue and the caffeine reduction liquid 6 after being taken out from the extraction tank 11 a is leached from the raw material 2 It holds the components such as theanine which has been lost. The decaffeinated green tea produced using this mixture is one in which the component derived from the raw material 2 is retained. In addition, when the manufacturing method shown in FIG. 3 is performed using the decaffeination treatment apparatus 1a, the mixture of the raw material residue and the caffeine reduction liquid 6 can be obtained without performing the mixing step, so the mixing step may be omitted. it can.

  When the liquid circulation process is completed, there are the raw material extract 5 and the caffeine reduction liquid 6 in the decaffeination processor 1a. Here, if the unextracted raw material 2 is newly prepared and the manufacturing method shown in FIG. 3 is subsequently performed, utilization of the raw material extract 5 and the caffeine reduction liquid 6 in the decaffeination treatment apparatus 1a Can.

  When the raw material 2 prepared newly is put into the extraction tank 11a and the liquid circulation process is repeated while utilizing the raw material extract 5 and the caffeine reduction liquid 6 in the decaffeination processor 1a, the raw material extract is repeated. 5 and the concentration of theanine etc. contained in the caffeine reduction solution 6 increase cumulatively. Eventually, the concentrations of theanine and the like contained in the raw material extract 5 and the caffeine-reduced liquid 6 reach equilibrium with the concentrations of theanine and the like contained in the raw material 2 and the raw material 4 during extraction. As a result, a mixture of caffeine reduction liquid 6 containing the raw material residue and theanine etc. in high concentration can be obtained in the liquid circulation step, so the decaffeinated green tea to be produced is Is the same as it was.

  When repeating the work of putting the newly prepared raw material 2 into the extraction tank 11a and performing the liquid circulation process while utilizing the raw material extract 5 and the caffeine reduction liquid 6, the cold water 3, the raw material extract 5 and the caffeine reduction liquid It is preferred to keep 6 below 5 ° C. When the temperature is kept at 5 ° C. or less, it is possible to suppress the growth of bacteria while suppressing the decomposition of theanine derived from apricot tea and the deterioration of pigment components. For this reason, the remaining raw material extract 5 and caffeine reduction solution 6 can be repeatedly used for a long time, and mass production of decaffeinated green tea becomes easy.

Fourth Embodiment
About the manufacturing method of the decaffeinated ground tea shown in FIG. 3 using the decaffeination processing apparatus 1b shown in FIG. 5, only the structure and effect different from the manufacturing method using the decaffeination processing apparatus 1a shown in FIG. Do. The decaffeination treatment apparatus 1b shown in FIG. 5 includes a sedimentation tank 21 and a filter 32 as compared to the decaffeination treatment apparatus 1a shown in FIG.

  As shown in FIG. 5, the precipitation tank 21 is provided below the extraction tank 11b. In addition, the extraction tank 11 b is provided with a tubular foot 15 extending in the vertical direction below the filter plate 14. The foot portion 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 settling tank 21 is in communication with the pipe 33. The pipe 33 communicates with the porous polymer resin 31, and a filter 32 is provided in a portion of the pipe 33 between the precipitation tank 21 and the porous polymer resin 31.

  When the manufacturing method shown in FIG. 3 is performed using the decaffeination processor 1b, an extraction step is performed in the extraction tank 11b, and the raw material extract 5 flows down from the filter plate 14 through the foot portion 15, and the precipitation tank 21 within. In the sedimentation tank 21, a fixed amount of the raw material extract 5 is stored. In the case where the raw material 2 has flowed out from the filtration bag 13, insoluble matters such as fragments of matcha or green tea are mixed in the raw material extract 5, but among the insoluble matters, the one having a large specific gravity is the inner bottom face of the precipitation tank 21. Deposit in the form of a precipitate 22. When the valve 24 of the pipe 25 communicating with the inner bottom surface of the settling tank 21 is opened, the sediment 22 can be discharged from the inside of the settling tank 21.

  Further, in the case where contaminants having a small specific gravity are mixed in the raw material extract 5, the contaminants become floating matter 23 in the vicinity of the water surface of the raw material extract 5 accumulated in the sedimentation tank 21. An overflow 28 is provided at the upper end of the inner wall surface of the settling tank 21, and when the raw material extract 5 is excessively stored in the settling tank 21, the suspended matter 23 flows into the overflow 28. Do. Here, when the valve 26 of the pipe 27 in communication with the overflow sludge 28 is opened, the floating matter 23 can be discharged from the sedimentation tank 21.

  The raw material extract 5 stored in the precipitation tank 21 flows in the piping 33 and contacts the porous polymer resin 31, but passes through the filter 32 before contacting the porous polymer resin 21. Although the raw material extract 5 flowing in the piping 33 contains fine fibers derived from a tailored leaf of mochi tea, the fine fibers are strained when the raw material extract 5 passes through the filter 32. . Even if the green tea that has flowed out of the filtration bag 13 may flow into the pipe 33, the green tea is also strained off by the filter 32. The filter 32 prevents fine fiber and green tea from coming into contact with the porous polymer resin 31.

  When the decaffeination treatment 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, it is possible to reduce the frequency of clogging of the porous polymer resin 31 due to insoluble matter and the like. Further, as compared with the case where a filter is used to protect the porous polymer resin by the manufacturing method shown in FIG. 1, since the decaffeination treatment apparatus 1b includes the settling tank 21, the frequency of clogging of the filter 32 is reduced. be able to. Since the decaffeination treatment device 1b can suppress the frequency of washing the porous polymer resin 31 and replacing the filter 32 low, it can be operated continuously for a long time, and the decaffeinated green tea can be further mass-produced.

Fifth Embodiment
With respect to the manufacturing method shown in FIG. 3 using the decaffeination processing apparatus 1c shown in FIG. 6, only the configuration and operational effects different from the manufacturing method using the decaffeination processing apparatus 1a shown in FIG. The decaffeination treatment apparatus 1c shown in FIG. 6 includes a filtration container 12 in the extraction tank 11c, as compared to the decaffeination treatment 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 is placed on the filter plate 14 of the extraction tank 11 c in a state where the raw material 2 is put in the container 12. The mixture of the raw material residue and the caffeine reduction liquid 6 can be removed from the extraction tank 11 c in the container 12. The filtration container 12 is such that when the filtration container 12 is placed on the filtration plate 14, a portion of the upper surface of the filtration plate 14 and the inner wall surface of the extraction tank 11 c above the filtration plate 14 is covered. It is a dimension.

  In the case where the prepared raw material does not contain green tea, the filtration container 12 has a structure in which a net member for filtration is attached between the frames of the frame members, and a filter cloth for food between the frames of the frame members. The thing of the structure which attached the is mentioned. When powdered green tea is contained in the prepared raw material, a fine filter cloth such as flannel, filter paper, paper filter used for brewing coffee, etc. may be used as the filtration container 12 between the frames of the frame member. 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. It can be put inside. When the filtration container 12 is provided, it is possible to reduce the time and effort of transferring the raw material 2 and the raw material residue and the like. In addition, during the liquid circulation process and the like using the decaffeination treatment apparatus 1c, a part of the raw material 4 is taken out during the extraction from the opening of the filtration container 12, and the additional raw material 2 is reduced by caffeine The amount of the raw material 2 or the raw material 4 during extraction can be adjusted as needed during the extraction process, such as being immersed in the liquid 6 or the like.

[Test method for color tone deterioration of powder such as raw material residue]
As a raw material, 100 g of tailored leaves of mochi tea and 1 L of distilled water at 5 ° C. as cold water were prepared. The raw material was packed in a flannel filtration bag, cold water was poured into a beaker, and the raw material was extracted by soaking the whole bag in cold water in a refrigerator at 5 ° C. The beaker was capped during the extraction.

  At 30 minutes after the start of extraction, the bag and the raw material were removed from the cold water and drained off to obtain a raw material during extraction. About 5 g of the raw material during extraction was collected, and the remaining unextracted raw material was extracted again by immersing in the same cold water with the bag. Similarly, extraction was continued while collecting about 5 g each of the raw material during extraction at 5 hours, 20 hours, 28 hours, 44 hours and 52 hours after the start of extraction. At 68 hours, the bag and the raw material during extraction were taken out from the cold water and drained off to obtain a raw material residue. About 5 g of the raw material residue was collected.

  The extracted raw materials and raw material residues collected during extraction are freeze-dried with a freeze dryer (FDU-810, manufactured by Tokyo Rika Kikai Co., Ltd.) to remove water, and crushed with an electric miller (EU-6820P, manufactured by Panasonic Corporation) During each extraction, dried powder of raw material or raw material residue was obtained. Further, for comparison, 5 g of specially prepared leaves of persimmon tea was newly prepared as a raw material, and the raw material without extraction was freeze-dried and crushed to prepare a dry powder of persimmon tea.

  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 Kogyo Co., Ltd .: ZE-2000) in accordance with JIS Z 8729. The color tone of the powder was measured, and the a value as an index of greenness was recorded in the Lab color system.

[Test result and consideration 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 larger the negative value, the stronger the green color tone, and the larger the positive value, the stronger the red color tone.

  As shown in Table 1, the a value of the powder of the raw material which was not subjected to the extraction process was -12.0. On the other hand, the a value of the powder of the raw material during extraction, which was obtained by extracting the raw material with cold water at 5 ° C, increased with the passage of time from -11.0 after 30 minutes, but after 68 hours It remained at-9.7 in powder. It has been shown that the extraction speed of the raw material bung tea with cold water at 5 ° C. extremely slows the deterioration of the color tone of the raw material from green to red. In addition, it was shown that even if the tailored leaves of mochi tea are extracted with cold water at 5 ° C. for 68 hours to produce matcha, it is possible to produce matcha with less deterioration of the inherent color tone of matcha. In addition, the same experimental result was obtained when using green tea as a raw material.

[Test method for color tone deterioration of decaffeinated green tea]
As ingredients, 5 g of tailored leaves of mochi tea and 150 ml of distilled water at 4 ° C. as cold water were prepared. The raw material was packed in a flannel filtration bag, cold water was poured into a beaker, and the raw material was extracted by soaking in the cold water together with the bag in a cold room at 4 ° C. At 72 hours after the start of extraction, the bag and the raw material were taken out of the cold water and drained off to obtain a raw material residue. The cold water left in the beaker was used as the raw material extract.

  The raw material extract is passed through a column filled with porous polymer resin (Amberlight FPX 66, manufactured by Dow Chemical Co.), and the raw material extract is brought into contact with the porous polymer resin to adsorb caffeine to obtain a caffeine-reducing liquid The The raw material residue and the caffeine reduction solution were separately freeze-dried separately to remove water in the above-mentioned lyophilizer, to obtain each dried product. The dry matter of the raw material residue was pulverized with the above-mentioned electric mill, to obtain a dry powder of the raw material residue. The dried product of the caffeine-reduced solution and the dried powder of the raw material residue were mixed with a medicine spoon so as to be substantially uniform, to obtain a sample of decaffeinated green tea of Example 1.

  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 ground as it was with a motor-driven miller to obtain a sample of matcha tea 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. Further, the samples of Examples 1 and 2 and Comparative Example 1 were subjected to high performance liquid chromatography, and the caffeine content and the theanine content of each sample were calculated using a calibration curve prepared as a standard. Furthermore, assuming that the content of each component of the sample of Comparative Example 1 is 100%, the retention of caffeine and the retention of theanine were calculated from the content of each component of the sample of Examples 1 and 2. .

The test results are shown in Table 2.

As shown in Table 2, while the a value of Comparative Example 1 was −12.0 , the a value of Example 1 is −9.4, and the a value of Example 2 is −11.1. Met. Since the difference between the a value of Comparative Example 1 and the a value of Examples 1 and 2 is small, Examples 1 and 2 have less deterioration in color tone as the quality control standard of the matcha maker is satisfied. In particular, from the results of Example 1, the raw material is extracted with cold water at 4 ° C. and the raw material extract is kept at 4 ° C. even if it takes 72 hours to extract, thereby producing decaffeinated green tea with little color deterioration. It was shown that it was possible.

The content of caffeine in Comparative Example 1 is 3.1% by weight , whereas the content of caffeine in Example 1 is 0.4% by weight, and the content of caffeine in Example 2 is Was 1.2% by weight. From the results of Example 1, it was shown that when extracted for 72 hours, the caffeine retention rate is 12.9%, and the caffeine content can be sufficiently reduced. From the results of Examples 2, extracted even time 30 minutes, the raw material in the majority of caffeine that is containing organic leached in cold water, the content of caffeine until retention is 38.7% It has been shown that it can be reduced.

  The content of theanine in Comparative Example 1 was 2.0% by weight, and the content in Examples 1 and 2 was 1.8% by weight. From the test results of Examples 1 and 2, when the raw material is extracted with cold water at 4 ° C., and each dried product obtained by freeze-drying the raw material residue and the caffeine-reduced solution is mixed, about 90% of theanine derived from the raw material It has been shown that it is possible to produce decaffeinated green tea that has been retained.

[Testing method of decaffeinated green tea and colored match of green tea, method of taste]
Prepare distilled water at about 0 ° C as cold water, extract the raw material with cold water in a cold room at 0 ° C over 5 hours, bring the raw material extract into contact with the porous polymer resin in a cold room at 0 ° C, and caffeine The decaffeinated green tea of Example 3 was produced under the same conditions as in Example 1 except that it was adsorbed. It was not seen that cold water, a raw material extract and a caffeine reducing solution solidified during production.

  The a value of Example 3 was measured by the method described above. Moreover, the sample of the green tea of the above-mentioned comparative example 1 was manufactured. The samples of Example 3 and Comparative Example 1 were used to spot Matcha, and the color of the spotted Matcha was visually compared by 10 panelists. Then, the taste was compared by drinking and comparing the dotted green tea by 10 panelists.

[The color of decaffeinated green tea and the color of dotted green tea, the test results and considerations of the flavor]
The test results for the color tone of Example 1 and Comparative Example 1 are shown in Table 3.

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

  Since the color was almost the same between the matcha green tea used in Example 3 and the matcha green tea used in Comparative Example 1, the panelists evaluated that no 10 of them were visually distinguishable. On the other hand, when comparing and drinking the matcha green tea which used the Example 3 and the matcha green tea which used the comparative example 1, it was evaluated that three panelists can not recognize the difference in a flavor, but seven panelers Of the green tea used in Example 3 was evaluated as having a more mellow and desirable flavor.

  Three panelists evaluated that they could not recognize the difference in flavor, because the raw material was extracted with cold water at about 0 ° C and freeze-dried, so that theanine was retained by 70% or more, and the aroma component was also retained. it is conceivable that. The reason why seven panelists evaluated that the matcha green tea used in Example 3 had a milder flavor was because the content of caffeine exhibiting a bitter taste was used for the matcha green tea used in Example 3 It is considered to be because the umami by theanine was enhanced because it was reduced. Alternatively, since the content of catechins exhibiting astringency is reduced by the porous polymer resin when producing the decaffeinated ground tea of Example 3, the possibility that the umami due to theanine may be enhanced is also considered.

  The decaffeinated green tea according to the present invention is a product in which the content of caffeine is sufficiently reduced with little deterioration of the original flavor and color tone of matcha, and the green tea can be used as a food material or as a raw material . The decaffeinated green tea according to the present invention is not limited to people who want to avoid taking caffeine, but can entertain people by providing the same color and flavor as uncaffeinated green tea. Furthermore, the above-mentioned decaffeinated green tea can be obtained by the method for producing decaffeinated green tea according to the present invention. Moreover, the decaffeination treatment apparatus according to the present invention can efficiently mass-produce the above-described decaffeinated green tea by using the above-described manufacturing 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 polymerization resin 41 Liquid feeding means

Claims (7)

A method for producing decaffeinated powdered green tea derived from a raw material selected from the group consisting of green tea leaves, powdered green tea , and mixtures thereof ,
A step of preparing the raw material,
By extraction immersed in cold water the material for 30 minutes or more, the raw material extract the cold water comprising a component containing caffeine extracted from the raw material, and the raw material to its content of caffeine an extraction step of obtaining a reduced raw material residues,
The raw material extract contains caffeine by contacting caffeine with the porous polymer resin by bringing the raw material extract into contact with a porous polymer resin which easily adsorbs caffeine but hardly adsorbs theanine. A decaffeination process to obtain a reduced amount of caffeine reduction solution,
Or lyophilized mixture of the raw material residue and the caffeine reduced liquid, or the raw material residue and the cafe by mixing in reducing solution from each lyophilized, freeze-dried product and the caffeine of the feed residue Obtaining a mixture of lyophilizates of the reduction solution, and
Only including,
The temperature of each of the cold water in which the raw material is immersed, the raw material extract liquid, the caffeine reducing liquid, and the raw material residue is maintained substantially at 15 ° C. or lower throughout the period from the extraction step to the drying step. A method of producing decaffeinated green tea characterized by A method for producing decaffeinated powdered green tea derived from a raw material selected from the group consisting of green tea leaves, powdered green tea , and mixtures thereof ,
A step of preparing the raw material,
A raw material extract comprising the component containing caffeine extracted from the raw material by extracting the raw material in cold water and extracting the extracted raw material with the content of caffeine reduced. an extraction step of obtaining an intermediate raw materials,
The raw material extract contains caffeine by contacting caffeine with the porous polymer resin by bringing the raw material extract into contact with a porous polymer resin which easily adsorbs caffeine but hardly adsorbs theanine. A decaffeination process to obtain a reduced amount of caffeine reduction solution,
The caffeine reduction liquid is circulated between the raw material during extraction and the porous polymerization resin, and the raw material during extraction is immersed in the caffeine reduction liquid being circulated to continue and circulate the extraction. A liquid circulation step of obtaining a raw material residue in which the content of caffeine in the extraction is reduced by repeating the contacting of the caffeine-reducing liquid with the porous polymerization resin,
Or lyophilized mixture of the raw material residue and the caffeine reduced liquid, or the raw material residue and the cafe by mixing in reducing solution from each lyophilized, freeze-dried product and the caffeine of the feed residue Obtaining a mixture of lyophilizates of the reduction solution, and
Only including,
The length of time during which the raw material is immersed in the cold water in the extraction step, and the length of time during which the raw material during extraction is immersed in the caffeine-reduced liquid circulated in the liquid circulation step, In total 30 minutes or more,
The temperature of each of the cold water in which the raw material is immersed, the raw material during extraction, the raw material extract, the caffeine reduction liquid, and the raw material residue is substantially measured from the extraction step to the drying step. A method for producing decaffeinated green tea characterized by keeping the temperature at 15 ° C. or less . The porous polymer resin, Amberlite (registered trademark) FPX66 a decaffeinated tea manufacturing method according to claim 1 or claim 2. A decaffeinated ground tea obtained by the method according to any one of claims 1 to 3 . A decaffeination processing apparatus comprising: an extraction tank in which a raw material selected from the group consisting of green tea tailored leaves, matcha green tea , and a mixture thereof is stored to extract caffeine,
In the extraction tank, the contained raw material is immersed in cold water and extracted , so that the cold water contains a component containing caffeine extracted from the raw material, and the raw material is the raw material An extraction raw material having a reduced content of caffeine is obtained , and the raw material extract is derived from the extraction tank,
Furthermore, a porous polymer resin provided so as to be in contact with the raw material extract solution derived from the extraction tank , caffeine is easy to adsorb, but theanine is difficult to adsorb ;
Said porous polymer resin in contact with caffeine reduce solution the raw material extract is reduced content of caffeine by adsorbed caffeine and, on the extracted middle ingredients contained in the extraction vessel A liquid feeding means for feeding and circulating between the raw material during extraction and the porous polymerization resin ;
Equipped with
During the extraction, the raw material is immersed in the caffeine-reduced liquid circulated by the liquid-feeding means to continue extraction, and the caffeine-reduced liquid and the porous material circulated by the liquid-feeding means By repeatedly bringing the polymer resin into contact, a raw material residue in which the content of the raw material during the extraction is reduced in caffeine content is obtained,
The length of time during which the raw material is immersed in the cold water, and the length of time during which the raw material during extraction is immersed in the caffeine-reduced liquid circulated by the liquid transfer means is at least 30 minutes in total. The cold water in which the raw material is soaked, the raw material during extraction, the raw material extract, and the caffeine, which are used so that the raw material is immersed in the cold water and the raw material residue is obtained. A decaffeination treatment apparatus characterized in that it is used to keep the temperature of each of the reduction liquid and the raw material residue substantially at 15 ° C. or less . Furthermore, a precipitation tank in which the raw material extract or the caffeine-reduced liquid circulated by the liquid transfer means is temporarily stored between the extraction tank and the porous polymer resin ;
The raw material extract liquid or the caffeine reduction liquid circulated by the liquid feeding means is provided so as to pass between temporarily accumulating in the precipitation tank and reaching the porous polymerization resin. Filters, and
The decaffeination processing apparatus according to claim 5 , comprising: The lyophilizer further includes a lyophilizer for lyophilizing the mixture of the raw material residue and the caffeine reduction liquid, or lyophilizing the raw material residue and the caffeine reduction liquid to mix the lyophilizate later.
The material residue and the caffeine-reducing solution are used so as to keep the temperature of each of the material residue and the caffeine-reducing solution substantially at 15 ° C. or less after obtaining each of the material residue and the caffeine-reducing solution until freeze-drying. The decaffeination processing apparatus described in claim 5 or claim 6 .

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