JP6313889B1 - Granulated tea leaves and method for producing the same - Google Patents

Abstract

An object of the present invention is to provide a granulated tea leaf that exhibits excellent dispersibility in water. Dispersion of granulated tea leaves in water is improved by containing 90% by mass or more of powdered tea leaves and setting the average particle size of the granulated tea leaves to 80 to 180 μm. [Selection figure] None

Description

  The present invention relates to a granulated tea leaf excellent in water dispersibility and a method for producing the granulated tea leaf.

  Usually, “tea” for drinking refers to an extract obtained by drying tea leaves without fermentation or fermentation and extracting them with water, warm water or hot water without crushing or crushing them. There is inconvenience that it must not.

  On the other hand, as a drinking tea that does not require the disposal of such extraction residue, the dried tea leaves, which are made into powdered tea with an average particle size of less than 10 μm with a jet mill or the like, are directly dispersed in hot water and stirred with a tea bowl or the like. Some are suspended for drinking. However, such powdered tea is inconvenient because the cost for making the average particle size 10 μm is very high and the dispersibility is very low.

  Therefore, recently, powdered tea that has been granulated by mixing powdered tea leaves with monosaccharides, disaccharides, starch degradation products, etc. as excipients has become the mainstream, so let's get better granulated powdered tea Various ideas have been made.

  For example, Patent Document 1 discloses that a granule comprising a shaped powder and a tea powder as a core and coated with a tea powder on its surface has a dispersibility in cold water while maintaining the taste, color and aroma. It is disclosed to be good. In Patent Document 2, green tea leaf powder and green tea extract are mixed, and after adding an excipient to this, it is vacuum-dried to a solid content of 40 to 85% by mass, thereby making it antioxidant. It is disclosed that an instant powdered tea that is rich and has a good dissolved color and is excellent in aroma, taste and solubility can be obtained. Furthermore, Patent Document 3 discloses a step of preparing a micronized liquid containing ground tea leaves (A) by pulverizing extraction and micronization of tea leaves (a) in an aqueous solution containing an antioxidant, and the resulting micronized liquid A step of adding a dry crushed tea leaf (B) obtained by pulverizing or grinding tea leaves (b) and a drying aid and stirring and mixing, and a step of drying the mixture obtained by stirring and mixing; It is disclosed that a dispersed tea that can be easily dissolved in water without using teacups can be obtained by passing through the above.

  In Patent Document 4, fine powdered tea having a particle size of 5 to 15 microns is granulated with a fluidized bed granulation coating apparatus using an air-flow type pulverizer, thereby achieving excellent dispersion and suspendability of 10 to 30 microns. It is disclosed that a powdered tea can be obtained. Furthermore, Patent Document 5 discloses that tea leaf granules having an angle of repose of less than 45 degrees, which is granulated by mixing 10 to 60% by mass of an indigestible dextrin as an excipient with 40 to 90% by mass of ground tea leaves, Alternatively, it is disclosed that when added to hot water, it is easily dispersed without becoming lumpy, and the green color, flavor and umami of tea leaves can be stably maintained.

  However, the granulated tea powders disclosed in Patent Documents 1 to 3 have a disadvantage that the production process is complicated, such as multistage granulation or the adoption of a tea extraction process before the granulation process. Further, the powdered tea disclosed in Patent Document 4 is not satisfactory in terms of dispersibility, and the tea leaf granule disclosed in Patent Document 5 requires a large amount of excipients, so There is a drawback that the original flavor is impaired.

JP 2000-342180 A Japanese Patent Laid-Open No. 06-178650 JP 2007-289115 A JP 2006-296341 A JP 2010-68741 A

  The subject of this invention is providing the granulated tea leaf which shows the outstanding dispersibility also to water.

  The present inventors have made various studies in order to solve this problem. Surprisingly, the powdered tea leaves are contained in an amount of 90% by mass or more, and the average particle diameter of the granulated tea leaves is set to 80 to 180 μm. It was found that the dispersibility of grain tea leaves in water was significantly improved. The present invention has been completed by further study based on such knowledge.

That is, this invention provides the invention of the aspect hung up below.
(1) Granulated tea leaves containing 90% by mass or more of powdered tea leaves and an average particle diameter of 80 to 180 μm.
(2) The granulated tea leaf according to (1), wherein the average particle size of the powdered tea leaf is 10 to 30 μm.
(3) A method for producing a granulated tea leaf, comprising wet granulating a raw material powder containing 90% by mass or more of powdered tea leaf to obtain a granulated tea leaf having an average particle size of 80 to 180 μm.
(4) The production method according to (3), wherein the wet granulation is performed by fluidized bed granulation.
(5) The condition for spraying the binder liquid is that the water increase rate calculated according to the following formula is 1.03 to 2.62% / min, and the water content of the granulated tea leaves at the end of spraying the binder liquid is 24 to The production method according to (4), wherein the granulation is performed with setting to be 35%.

  When the granulated tea leaves of the present invention are added to water and mixed, they can be easily dispersed without causing lumps. In addition, the granulated tea leaf of the present invention uses almost no excipient for granulation, so that it has a low volume and is convenient, and also has an adverse effect on the taste of the excipient, thereby reducing the original tea leaves. It is also possible to exhibit a good flavor.

It is the photograph which image | photographed the external appearance (evaluation of dispersibility (double-circle)) at the time of disperse | distributing the granulated tea leaf of Example 1 in 20 degreeC water. It is the photograph which image | photographed the external appearance (dispersion evaluation (circle)) at the time of disperse | distributing the granulated tea leaf of Example 1 to 60 degreeC water. It is the photograph which image | photographed the external appearance (dispersion evaluation x) at the time of disperse | distributing the granulated tea leaf of the comparative example 3 in 20 degreeC water.

  The granulated tea leaf of the present invention is characterized by containing 90% by mass or more of powdered tea leaf and having an average particle size of 80 to 180 μm. Hereinafter, the granulated tea leaves of the present invention will be described in detail. The term “granulated tea leaf” refers to a product obtained through a series of granulations including the final drying step, and the term “granulated tea leaf at the end of spraying the binder liquid (or water)” This refers to granulated tea leaves that have not undergone the final drying step in a series of granulations.

  The type of tea leaves of the powdered tea leaves contained in the granulated tea leaves of the present invention is not particularly limited, for example, green tea, barley young leaves, kale, morohaya, wormwood, barley tea, hato barley tea, etc .; semi-fermented oolong tea etc. Tea leaves: fermented tea leaves such as black tea. Among these, green tea leaves are preferable. In addition, the term “powdered tea leaves” in the present invention is not included in the narrowly defined “powdered tea leaves”, such as “Matcha”, since the raw material is “boiled tea” and no savory work is performed. Used in a broad sense and includes “matcha”.

  Powdered tea leaves can be obtained by pulverizing the tea leaves, semi-fermented tea leaves, or fermented tea leaves. The powdering method is not particularly limited, and examples thereof include a powdering process by an airflow type or a mixer type pulverization method.

  Although it does not restrict | limit especially about the average particle diameter of a powdered tea leaf, For example, 5-40 micrometers is mentioned. From the viewpoint of providing further excellent dispersibility, the average particle diameter of the powdered tea leaves is preferably 10 to 40 μm, more preferably 20 to 30 μm. In the present invention, the “average particle diameter of powdered tea leaves” is a median diameter measured using a laser diffraction / scattering particle size distribution measuring apparatus.

  The content of the powdered tea leaf in the granulated tea leaf of the present invention is set to 90% by mass or more. Thus, it becomes possible to provide excellent dispersibility by setting the average particle diameter of the granulated tea leaves within a predetermined range described later while increasing the content of the powdered tea leaves. From the viewpoint of providing excellent dispersibility while further reducing the bulk of the granulated tea leaf, the content of the powdered tea leaf in the granulated tea leaf of the present invention is preferably 95% by mass or more, more preferably 98% by mass or more. More preferred is 99% by mass or more, and particularly preferred is 100% by mass. In the present invention, the content of the powdered tea leaf is a value calculated by excluding the content of water inevitably absorbed or remaining in the granulated tea leaf.

  The granulated tea leaf of the present invention preferably contains an excipient when the content of the powdered tea leaf is less than 100% by mass. The type of excipient used in the present invention is not particularly limited as long as it can be used in foods, and examples thereof include adhesive materials such as starch degradation products, starch, saccharides and thickening polysaccharides. It is done. These excipients may be used alone or in combination of two or more.

  Among these excipients, starch decomposition products are preferable. Although it does not restrict | limit especially about DE (dextrose equivalent) of the starch degradation product used by this invention, For example, DE8-25, Preferably DE8-18 is mentioned.

  When the granulated tea leaves of the present invention contain an excipient, the content thereof is 10% by mass or less, preferably 0.1 to 10% by mass, more preferably 0.1 to 5% by mass, particularly preferably. 0.1-2 mass%, Most preferably, 0.1-1 mass% is mentioned. In the present invention, the content of the excipient is a value calculated by excluding the content of water inevitably absorbed or remaining in the granulated tea leaves.

  The average particle diameter of the granulated tea leaves of the present invention is set to 80 to 180 μm. It becomes possible to provide excellent dispersibility with respect to water, hot water, and hot water by satisfying the above-described range of the content of the powdered tea leaves while having such an average particle diameter. From the viewpoint of further improving dispersibility, the average particle size of the granulated tea leaves of the present invention is preferably 90 to 180 μm, more preferably 95 to 180 μm.

In the present invention, the average particle size of the granulated tea leaves is a value measured by a sieving method. The method for measuring the average particle size of the granulated tea leaves is specifically as follows. First, prepare sieves with 53, 63, 75, 106, 150, and 250 μm openings, and stack them so that the one with the small opening is the bottom and the one with the large opening is the top. Place the brown tea leaves on the lid and apply vibration with a vibrator. Next, the weight of each sieved granulated tea leaf is measured. The average particle diameter (weight-based cumulative 50% value) is calculated according to the following calculation formula.

  The particle size distribution of the granulated tea leaf of the present invention is not particularly limited as long as the average particle size described above is satisfied. As a ratio of the weight of the granulated tea leaf of 106 μm or more and less than 150 μm to the total weight of the granulated tea leaf, for example, 20 % Or more, specifically 20% or more and less than 35%. Here, “the ratio of the weight of the granulated tea leaf of 75 μm or more and less than 150 μm to the total weight of the granulated tea leaf” is a value obtained by a sieving method under the same conditions as the measurement of the average particle diameter.

  The granulated tea leaves of the present invention are produced by granulating to the above-mentioned average particle diameter using raw material powder containing powdered tea leaves and excipients added as necessary. The granulation method for producing the granulated tea leaves of the present invention is not particularly limited as long as the above-mentioned granulated product having an average particle diameter can be obtained, and either a wet granulation method or a dry granulation method. Although there may be, wet granulation method is mentioned preferably.

  When the granulated tea leaf of the present invention is produced by a wet granulation method, it may be performed by any granulation method such as fluidized bed granulation, rolling granulation, stirring granulation, extrusion granulation, etc. From the viewpoint of efficiently producing granulated tea leaves having an average particle size, a fluidized bed granulation method is preferably used.

  When the granulated tea leaf of the present invention is produced by a wet granulation method, water is used as a binder liquid, and spraying or the like is performed on the raw material powder (a raw material containing powdered tea leaves and excipients added as necessary). What is necessary is just to add. In addition, when the granulated tea leaf of the present invention contains an excipient, a part or all of the excipient contained in the granulated tea leaf may be dissolved or dispersed in the water used as the binder liquid. Good. When the excipient is dissolved or dispersed in the water used as the binder liquid, the concentration of the excipient in the water used as the binder liquid may be set to about 0.1 to 20 w / v%, for example.

When the granulated tea leaves of the present invention are produced by a wet granulation method, the wet granulation conditions are not particularly limited as long as the above-mentioned granulated product having an average particle diameter is obtained. In the case of the grain method, the rate of water increase calculated according to the following formula is 1.03 to 2.62% / min, preferably 1.36 to 2.62% / min, and more preferably 1.66 to The content of the binder liquid is 2.62% / min, and the water content of the granulated tea leaves at the end of spraying of the binder liquid is 24 to 35%, preferably 26 to 35%, and more preferably 30 to 34%. By controlling the spraying conditions, the above-mentioned granulated product having an average particle diameter can be efficiently produced.

  The “moisture content of the granulated tea leaf” and the “moisture content of the raw material powder” are values measured at a set temperature of 105 ° C. using an infrared moisture meter. The “binder liquid spraying time” is the time required from the start of spraying the binder liquid to the end of spraying a predetermined amount of the binder liquid, and the spraying of the binder liquid is continuously performed within the spraying time of the binder liquid. Alternatively, the binder liquid may be sprayed intermittently. As an aspect which sprays a binder liquid intermittently, the aspect which repeats the said cycle by making spraying of a binder liquid, stop, wiping off, and stopping into 1 cycle is mentioned, for example. In the case where the binder liquid is sprayed intermittently, the “binder liquid spraying time” includes the time required for the stop and removal.

  In the fluidized bed granulation method, in order to adjust the spray condition of the binder liquid so that the moisture increase rate and the moisture content of the granulated tea leaf at the end of spraying are within the above ranges, the spray amount of the binder liquid on the raw material powder, the binder What is necessary is just to control the spraying speed of a liquid, the supply temperature to the inside of a granulator, etc. suitably. Specifically, if the supply temperature into the granulator is set in the range of 20 to 40 ° C., the amount of binder liquid to be used (sprayed) per 100 parts by mass of the raw material powder is 30 to 80 parts by mass, Preferably, it is appropriately set within the range of 40 to 80 parts by mass, more preferably within the range of 50 to 70 parts by mass, and the spray rate of the binder liquid per 1 kg of the raw material powder is appropriately set within the range of 4.8 to 63 ml / min. That's fine. Here, the spray rate of the binder liquid per 1 kg of the raw material powder is a value obtained by dividing the spray rate of the water supplied into the wet granulator by the weight (Kg) of the raw material powder used for the wet granulation. Point to.

  In addition, when maintaining the flavor of granulated tea leaves, it is desirable to set the temperature of the air supplied to the granulator within a range of 20 to 40 ° C. However, if the air supply temperature into the granulator is set to less than 20 ° C., the spray rate of the binder liquid is made lower than the above range, and / or the binder liquid amount per 100 parts by mass of the raw material powder is By reducing the amount from the range, etc., it is possible to adjust the water rising rate and the water content of the granulated tea leaf at the end of spraying to satisfy the above range. Further, if the supply temperature into the granulator is set to more than 40 ° C., the spray rate of the binder liquid is made higher than the above range, and / or the binder liquid amount per 100 parts by mass of the raw material powder is It can be adjusted so that the moisture increase rate and the moisture content of the granulated tea leaf at the end of spraying satisfy the above range by increasing the range or the like. Also, the rate of moisture rise and the amount of water in the granulated tea leaves at the end of spraying are affected by the size of the fluidized bed granulator used, the amount of raw material powder, etc., so the size of the fluidized bed granulator used Based on the amount of the raw material powder, the amount of the binder liquid sprayed on the raw material powder, the spray rate of the binder liquid, the supply temperature into the granulator, etc. may be set appropriately with reference to the above range. .

  In the fluidized bed granulation method, after spraying of the binder liquid is completed under the above conditions, the granulated tea leaf of the present invention is obtained by continuously drying in the fluidized bed granulator until a desired water content is obtained.

  The granulated tea leaves obtained by granulation may be adjusted in size and the particle diameter may be adjusted as necessary.

  Examples of the present invention will be described in detail below, but the present invention is not limited thereto.

Test example 1
1. Manufacture of granulated tea leaves First, 2 kg of domestically produced tea tea powder (hereinafter referred to as “raw green tea”) is put into a type 5 fluidized bed granulator (flow coater, Freund Sangyo Co., Ltd.), and 20 ° C. air sucked from an exhaust fan It was made to flow by blowing from the bottom. Next, 1000 ml of 80 ° C. water (binder liquid) is sprayed on the raw material matcha tea and granulated, and after the spraying is completed, drying is continued under the conditions of a supply air temperature of 100 ° C. and 30 minutes, whereby the granulated tea leaves are obtained. Obtained. In addition, the average particle diameter of the raw material matcha used, the spray speed of water, and the spray time of water are as shown in Table 1 below. Water spraying was performed intermittently by repeating the cycle with “40 seconds spray + 1 second stop + 10 seconds wiped off + 1 second stop” as one cycle. The average particle diameter of the raw material matcha is a median diameter measured using a laser diffraction / scattering particle size distribution measuring device (MT3000, manufactured by Nikkiso).

  In addition, the raw material matcha before spraying water and the granulated tea leaves at the end of spraying are sampled, and the moisture content is measured at a set temperature of 105 ° C. using an infrared moisture meter (“FD-610”, manufactured by Kett Science Laboratory Co., Ltd.). Measurements were made. The water increase rate was calculated according to the calculation formula using the obtained water content values. The results are shown in Table 1.

2. Measurement of average particle size and particle size distribution of granulated tea leaves Screens with 53, 63, 75, 106, 150, and 250 μm openings are placed in order from the finest and stacked in six stages, and granulated on the uppermost sieve. 20g of tea leaves were put in, covered, and shaken with a vibrator (IIDA SIEVE SHAKER Iida Seisakusho) for 10 minutes from the top of the lid to vibrate, and the weight of the granulated tea leaves present on each sieve was measured. The weight ratio (distribution ratio (%)) of the granulated tea leaves on each sieve to the granulated tea leaves subjected to the measurement was calculated. Moreover, the average particle diameter was calculated | required according to the above-mentioned calculation formula. The obtained results are shown in Table 2.

3. Evaluation of dispersibility of granulated tea leaves Add 0.5 g of granulated tea leaves to 100 ml of water at 20 ° C. and 60 ° C. with stirring, and after stirring for 10 seconds, visually observe the dispersibility of the suspension and disperse according to the following criteria. Sex was evaluated.
(Distribution criteria)
A: Dama does not occur. O: Number of generated lumps is less than 10. X: Number of generated lumps is 10 or more. A lump of 5 mm or more is defined as “dama”.

  The obtained results are shown in Table 3. For reference, the photograph of the appearance (evaluation of dispersibility) when the granulated tea leaves of Example 1 are dispersed in 20 ° C. water is shown in FIG. 1, and the granulated tea leaves of Example 1 are 60 ° C. A photograph of the appearance (dispersibility evaluation 0) taken when dispersed in water of FIG. 2 and the appearance when the granulated tea leaves of Comparative Example 3 are dispersed in water at 20 ° C. (dispersibility evaluation ×). The photograph which image | photographed is shown in FIG.

  From this result, it was confirmed that the granulated tea leaves (Examples 1 to 5) having an average particle diameter of 80 to 180 μm exhibit excellent dispersibility in both 20 ° C. and 60 ° C. water.

Test example 2
1. Manufacture of granulated tea leaves First, 2 kg of domestically produced tea tea powder (hereinafter referred to as “raw green tea”) is put into a type 5 fluidized bed granulator (flow coater, Freund Sangyo Co., Ltd.), and 20 ° C. air sucked from an exhaust fan It was made to flow by blowing from the bottom. Next, granulated tea leaves are obtained by spraying water (binder liquid) at 80 ° C. to the raw material matcha tea, followed by drying at the supply temperature of 100 ° C. and 30 minutes after the spraying is completed. It was. In addition, the average particle diameter of the raw material matcha used, the amount of sprayed water, the spray speed of water, and the spray time of water are as shown in Table 4 below. Water spraying was performed intermittently by repeating the cycle with “40 seconds spray + 1 second stop + 10 seconds wiped off + 1 second stop” as one cycle. The average particle diameter of the raw material matcha is a median diameter measured using a laser diffraction / scattering particle size distribution measuring device (MT3000, manufactured by Nikkiso). In addition, the raw material matcha before spraying water and the granulated tea leaves at the end of spraying are sampled, and the moisture content is measured at a set temperature of 105 ° C. using an infrared moisture meter (“FD-610”, manufactured by Kett Science Laboratory Co., Ltd.). Measurements were made. The water increase rate was calculated according to the calculation formula using the obtained water content values.

2. Evaluation of average particle diameter and dispersibility of granulated tea leaves The obtained granulated tea leaves were evaluated for average particle diameter and dispersibility under the same conditions as in Test Example 1. The results are shown in Table 5. As a result, it was confirmed that Examples 1, 6, 7, 8, and 9 had an average particle diameter of 80 to 180 μm and exhibited excellent dispersibility in both 20 ° C. and 60 ° C. water. It was done. On the other hand, Comparative Example 5 had an average particle size of less than 80 μm and poor dispersibility. In Comparative Example 6, the amount of water at the end of water spraying was as high as 36.1%, and flow failure occurred during production, making it impossible to produce granulated tea leaves.

Test example 3
1. Manufacture of granulated tea leaves Domestic tea tea powder (hereinafter referred to as “raw green tea”) and excipients (powder cake (starch degradation product), DE25, “MPD” manufactured by Matsutani Chemical Co., Ltd.) at the ratios shown in Table 6 2 kg of the mixed raw material powder was put into a type 5 fluidized bed granulator (flow coater, Freund Sangyo Co., Ltd.), and 20 ° C. air sucked from an exhaust fan was blown from the bottom to flow. Next, 1000 ml of 80 ° C. water was sprayed on the raw material powder for granulation, and after the spraying was completed, drying was continued under conditions of an air supply temperature of 100 ° C. and 30 minutes to obtain granulated tea leaves. In addition, the average particle diameter of the raw material matcha used, the spraying speed of water, and the spraying time of water are as shown in Table 6 below. Water spraying was performed intermittently by repeating the cycle with “40 seconds spray + 1 second stop + 10 seconds wiped off + 1 second stop” as one cycle. The average particle diameter of the raw material matcha is a median diameter measured using a laser diffraction / scattering particle size distribution measuring device (MT3000, manufactured by Nikkiso). The average particle diameter of the raw material matcha is a median diameter measured using a laser diffraction / scattering particle size distribution measuring device (MT3000, manufactured by Nikkiso). In addition, the raw material powder before spraying water and the granulated tea leaves at the end of spraying (in the case of Comparative Example 7) are sampled, and an infrared moisture meter (“FD-610”, manufactured by Kett Science Laboratory Co., Ltd.) is used. The moisture content was measured at a set temperature of 105 ° C. The water increase rate was calculated according to the calculation formula using the obtained water content values.

  In Examples 1 and 10, granulated tea leaves were obtained without causing trouble during production, but in Comparative Example 7, the proportion of excipients was large and the proportion of raw material matcha was small, so poor flow during production. There has occurred. Therefore, measurement of the average particle diameter and evaluation of dispersibility shown below were performed using the granulated tea leaves of Examples 1 and 10.

2. Evaluation of average particle diameter and dispersibility of granulated tea leaves The obtained granulated tea leaves were evaluated for average particle diameter and dispersibility under the same conditions as in Test Example 1. The results are shown in Table 7. As a result, it was confirmed that the granulated tea leaves having an average particle diameter of 80 to 180 μm have good dispersibility even when containing 10% by mass of the excipient.

Claims (3)

  Granulated tea leaves containing 90% by mass or more of green tea powder tea leaves and an average particle size of 80 to 180 μm.   The granulated tea leaf according to claim 1, wherein the average particle size of the green tea powder tea leaf is 10 to 30 µm. A method for producing granulated tea leaves, comprising:
Wet granulating a raw material powder containing 90% by mass or more of green tea powder tea leaves, and obtaining a granulated tea leaf having an average particle size of 80 to 180 μm ,
The wet granulation is performed by fluidized bed granulation,
The spray condition of the binder liquid is such that the rate of water rise calculated according to the following formula is 1.03 to 2.62% / min, and the water content of the granulated tea leaves at the end of spraying the binder liquid is 24 to 35%. The manufacturing method which is set and granulated.