JP2002125593A - Finely powdered and classified tea and method for producing finely powdered and classified tea - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a powdered tea (namely finely powdered and classified tea) in which particle size is small and the particle size area is limited and provide a food containing the finely powdered and classified tea. SOLUTION: This method for producing finely powdered and classified tea includes a step for powdering a tea raw material and a step for classifying finely powdered tea obtained by the above step. This finely powdered and classified tea is obtained by the above method. This food includes the finely powdered and classified tea.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a ground tea having a small particle size obtained by classifying a ground tea and having a limited particle size range (namely, a finely ground classified tea). The present invention also relates to a method for producing the finely ground classified tea, and to a food containing the finely ground classified tea.

[0002]

2. Description of the Related Art Conventionally, ground tea is obtained by grinding tea raw materials (such as tencha, green tea, black tea, oolong tea, or other wild grass tea) using a grinder such as a stone mill, a ball mill, a jet mill, and a pin mill. Had been manufactured.

[0003] Ground tea can be generally used for processed foods. When used in processed foods, the effect of the characteristics such as color and aroma can be obtained by adding and mixing about 0.1 to 10% by weight. Foods that can be used include noodles (various noodles such as soba, udon, ramen), ice creams (ice cream, ice cream, soft ice cream, etc.), baked goods (bread, cake, sponge, cookies, etc.), drinks (Green tea, matcha milk, matcha milk, lactic acid drinks, etc.), fish paste products (kamaboko, chikuwa, hampan, sausage, fried fish, etc.), rice crackers (mochi, senbei, hail, etc.), candy, etc.

[0004] When the ground tea is mixed with the food as described above,
While properties such as the color and scent of the tea can be used, inconveniences may result from mixing the ground tea with the original product. For example, when crushed tea is added to a beverage, there is a problem that large-sized particles precipitate and must be mixed before drinking. Further, a product filled in a transparent or translucent container has an adverse effect such as poor appearance and reduced commercial value. In addition, when mixed with noodles such as udon and the like, if crushed tea is added to flour as a raw material, the connection of udon is deteriorated, and a phenomenon occurs in which the elasticity peculiar to udon is lost. Further, it is known that when added to and mixed with bread, the swelling of the bread when baked becomes worse.

[0005] Therefore, there is a demand for finer ground tea in food processing, which is further promoted by the recent division of food processing, and there is a demand for finer ground tea. With the demand for such finely ground tea, the above-mentioned various pulverizers have been used, but to date, only an evaluation equivalent to pulverization with a stone mill has been obtained. The particle size of the conventional ground tea has a particle size distribution ranging from about 1 μm to several tens of μm, although there are differences depending on the grinding method, the type of the pulverizer, and the type of the tea raw material to be ground (FIG. 1). See the particle size distribution of normal matcha).

As described above, conventionally, it has been attempted to produce finely pulverized tea by pursuing the pulverization technique. For example, in the case of producing finely ground tea using a stone mill, methods such as increasing the weight of the upper mill or increasing the residence time of the raw material in the mill have been considered. However, when the weight of the upper mill is increased, there is a problem that the ground product is biased by the load, and even if the residence time is further increased, a particularly fine product cannot be obtained. When a machine such as a ball mill is used, it is known that the longer the operation time, the smaller the average particle size, but the 90% cumulative frequency diameter hardly changes. As described above, in the conventional machine, it is generally possible to reduce the average particle size by increasing the residence time, but large particles (90% cumulative frequency diameter) do not change much.

[0007]

In view of the above circumstances, the cause of the conventional ground tea showing a wide particle size distribution was examined. The present inventors have found that raw materials such as Tencha, green tea and the like are made of plant leaves and stems, so even if hard parts such as stems and leaf veins are crushed, they remain as large particles and show a particle size distribution of Ssansan. I came to the idea. That is, because of the hard part of the raw material, it was concluded that fine pulverized tea could not be obtained even with various pulverizers.

Accordingly, it is an object of the present invention to provide a ground tea having a small particle size and a limited particle size range (namely, a finely classified tea), a method for producing the finely classified tea, and An object of the present invention is to provide a food containing the finely classified tea.

[0009]

The object of the present invention has been attained by the following means.

(1) A method for producing a finely classified tea, comprising a step of pulverizing a tea raw material and a step of classifying the pulverized tea obtained in the above step.

(2) Finely ground classified tea obtained by the method described in (1).

(3) The finely divided and classified tea according to (2), wherein the number of particles having a particle size of 10 μm or less is 90% or more of the total number of particles of the finely divided and classified tea.

(4) A food comprising the finely divided classified tea according to (2) or (3).

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

[Method of Producing Finely-Pulverized Classified Tea] The method of producing finely-pulverized classified tea according to the present invention comprises a first step of pulverizing tea raw materials and a second step of classifying the pulverized tea obtained in the above step. It is characterized by including.

The tea raw material used in the present invention is not particularly limited, as long as it can be added to food after grinding, such as tea, green tea, black tea, oolong tea, or other wild grass tea. Among them, preferably, tea is used.

In the method for producing a finely divided and classified tea of the present invention, in the first step, the above-mentioned tea raw material is pulverized by a known method using a pulverizer such as a stone mill, a ball mill, a jet mill, and a pin mill. In the first step, it is desirable to pulverize to a degree that does not cause roughness. In this pulverization step, several pulverizers may be used in combination. By this step, a ground tea having a wide particle size distribution is obtained (see the particle size distribution of normal matcha in FIG. 1).

Next, in a second step, the ground tea is classified. The classification operation is applied to those used in manufacturing techniques that require high precision pulverization classification, such as toner for printing, pharmaceuticals, powder coatings, and new ceramics. For this operation, for example, a classifier described in Examples described later, a DS-2 classifier manufactured by Nippon Pneumatic Industries, Ltd., or the like can be used.

By this classification operation, a ground tea having a desired particle size distribution and a uniform and fine particle size can be obtained.
Preferably, a ground tea having an average particle size range of 0.1 to 20 μm, more preferably 0.1 to 8 μm is obtained. Also, preferably,
Of the total number of ground tea particles, 90
% Or more, more preferably 90% of particles having a particle size of 15 μm or less.
As described above, most preferably, ground tea having a particle size of 10 μm or less and 90% or more of particles is obtained. In the present invention, the term "finely ground classified tea" refers to ground tea obtained through a classification operation, and preferably ground tea having a particle size as defined above.

[Pulverized Classified Tea] The desired finely divided classified tea obtained by the method of the present invention preferably has an average particle size range of 0.1 to 20 μm, more preferably 0.1 to 20 μm, as described above.
８8 μm. Also, preferably, 90% or more of the number of particles having a particle size of 20 μm or less, more preferably 90% or more of the particles having a particle size of 15 μm or less, and most preferably 10% or less of the particle size of the ground tea. The number is 90% or more.

Such finely classified tea has an excellent effect when it is added to food, because it has a small average particle size and a limited particle size range.

[Food Containing the Finely-Grained Classified Tea of the Present Invention] By adding the above-mentioned finely-grained classified tea of the present invention to a food, a food having a tea color, taste and flavor can be obtained.

The food to which the finely classified tea of the present invention is added is not limited as long as it is a food suitable for adding the color, taste and flavor of tea. Typical examples include drinks, noodles, ice creams, baked confectionery and the like as described in the prior art. The amount of the finely divided classified tea of the present invention added to food is preferably 0.01 to 30% by weight, more preferably 0.1 to 10% by weight. Further, the finely ground classified tea of the present invention can be added and mixed at any time during food processing.

The food containing the finely divided classified tea of the present invention has the following advantages.

By providing the finely ground tea of the present invention to a beverage or the like, it is possible to solve the problem caused by the precipitation caused by the conventional ground tea. For example, a ground tea having a particle size (particle size) of 1 μm has a volume of 4.2 μm ³ when calculated as a true sphere, whereas a ground tea having a particle size of 10 μm has a volume of about 42 μm.
00 μm ³ , indicating a 1000-fold volume. That is, if the average particle size is different by 10 times, the volume will be 1000 times different. In addition, the ground tea having a particle size of 1 μm and the ground tea having a particle size of 10 μm have the same specific gravity of the ground tea. From this, the fine ground tea of the particles of the present invention, when mixed with food,
It is suggested that it can be an additive that does not cause precipitation.

Further, by using it in ice cream or the like, it becomes possible to provide a texture that is far more smooth than conventional kneaded tea.

Furthermore, when the finely ground classified tea of the present invention is added to food, the number of particles per unit amount is increased as compared with conventional ground tea, and the effect of improving the apparent color is also exhibited.
For example, crushed tea particle size (particle diameter) is 1μm, calculated as a sphere, although the area on the projection is 0.79 .mu.m ^2, particle size which 78.5 ² becomes a 10μm grinding tea, the 100 times the area Show. This indicates that the addition of the same weight of ground tea into the bulk of the food product increases the apparent surface area of the ground tea particles appearing on the surface by a factor of 100. Therefore, it becomes possible to improve the apparent color per unit weight of the ground tea during food processing.

[0028]

Embodiments of the present invention will be described below.

Example 1 Classification of Matcha First, Tencha was ball milled (BM-Makino Co., Ltd.)
100 type) to obtain ground tea. This ground tea is hereinafter referred to as “normal matcha”. Next, for the obtained "normal matcha", manufactured by Nippon Pneumatic Industries,
Classify using a DS-2 classifier, etc., and use “Normal Matcha”
Crushed tea with finer and more uniform particle size was obtained. This is hereinafter referred to as "fine powder matcha".

FIG. 1 shows the particle size distribution of “normal matcha” and “fine powdered matcha”, and FIG. 2 shows the cumulative frequency distribution of the particle size. FIG. 1 shows the number of particles corresponding to each particle size by frequency (%) with respect to the total number of particles, and FIG. 2 shows the cumulative number of particles up to each particle size by frequency (%) with respect to the total number of particles. In FIG. 2, the particle diameter when the cumulative number of particles reaches a% of all particles is referred to as “a% cumulative frequency diameter”.

Table 1 shows a comparison of the particle sizes of "normal matcha" and "fine powdered matcha". In the present invention, the particle size was measured by a particle size distribution analyzer FRA (manufactured by Microtrack).

[0032]

[Table 1]

The particle size distribution, which had been bimodal in "normal matcha" before classification, was almost normal in "fine powdered green tea" after classification (FIG. 1). As a result, the median diameter (50% cumulative frequency diameter) of “Normal Matcha” before classification was 11.5.
It was 2 μm, but 3.18 μm for “fine powdered green tea” after classification.
The particle size was reduced to 3.6 times (FIG. 2 and Table 1).
In addition, the value of the mode diameter indicating the most frequent particle size was 16.88 μm for “normal matcha” before classification, but was 3.79 μm for “fine powdered matcha” after classification, which was 1 / 4.5 of the particle size. (Table 1). Furthermore, it is an indicator that indicates the roughness of matcha and indicates large particles that tend to precipitate when used in beverages.
The% cumulative frequency diameter was 39.38 μm for “Normal Matcha” before classification, but was 6.90 μm for “Fine powdered green tea” after classification.
The particle size was reduced to 1/7 (FIG. 2 and Table 1). By performing the classification operation in this way, a homogeneous finely ground tea having a small particle size could be obtained.

Example 2: Beverage (when suspended in water) The "normal matcha" obtained in Example 1 was added to water in an amount of 1, 2, 4, or 8% by weight, and was well suspended. mL. Similarly, "fine powdered green tea" obtained in Example 1 was added to water for 1, 2,
Suspend well with 4 or 8% by weight, and add 10
Make up to 0 mL. These were each placed in a measuring cylinder, and the amount of sedimentation was measured at regular intervals. The amount of sedimentation was based on the sedimentation line appearing on the measuring cylinder. The results are shown in Table 2 and FIG.

[0035]

[Table 2]

The sedimentation line is 1% concentration of "normal matcha"
The sedimentation line appeared after 15 minutes, whereas the 1% concentration of “fine powdered green tea” only slightly appeared after 60 minutes (Table 2).
And FIG. 3). In addition, the sedimentation line after 240 minutes was found at 6.5 mL for "Normal Matcha" and 0.9 mL for "Fine Powdered Matcha" in both Matcha at 1% concentration (Table 2 and FIG. 3). ). In addition, in both Matcha of 8% concentration,
"Normal matcha" showed a settling line at 98.7 mL after 15 minutes, and at 89.8 mL after 240 minutes,
In the case of “fine powdered green tea”, a sedimentation line could be confirmed only after 240 minutes, and the position was 97.7 mL (Table 2).

In addition, the “normal matcha” obtained in Example 1 was added to water.
0.5, 1.0, or 2.0% by weight of the suspension well suspended,
A "normal matcha" suspension was prepared. Similarly, the “fine powdered green tea” obtained by adding 0.5, 1.0, or 2.0% by weight of “fine powdered green tea” obtained in Example 1 to water was well suspended to prepare a suspension of “fine powdered green tea”. The color of each suspension was evaluated by measuring each of the green tea suspensions with a color difference meter (Spectro Color Meter SE2000, manufactured by Nippon Denshoku Industries Co., Ltd.). The results are shown in Table 3 and FIG.
6 to FIG.

In Table 3 and FIGS. 4 to 6, the L value represents “brightness”, and the larger the value, the stronger the brightness. The a value and the b value represent “chromaticity” indicating hue and saturation, and the a value is a positive value representing a red color and a negative value representing a green color. As for the b value, a positive value indicates a color in the yellow direction, and a negative value indicates a color in the blue direction. The a-value and the b-value, both positive and negative values, mean that the color becomes more vivid as the number increases, and the color becomes duller as the number approaches zero.

[0039]

[Table 3]

The results of measurement of the surface color also supported the good color of "fine powdered green tea" as a whole. That is, in the a value which is a green index (the larger the minus number, the darker the green), even 0.5% density “fine powdered green tea” is 2.0%.
The results showed that the surface color was superior to that of the “normal matcha” at a% concentration (Table 3 and FIG. 5).

Example 3: Noodles (buckwheat) 140 g of buckwheat flour and 60 g of flour were mixed, and 2% by weight or 4% by weight of "normal matcha" obtained in Example 1 was added thereto, followed by sufficient stirring. Similarly, the “fine powdered green tea” obtained in Example 1
% By weight or 4% by weight and stirred well. To each of the mixed powders, water was added in several portions so as to have a water content of 45%, and the mixture was well watered during the addition. The final water content was slightly adjusted depending on the hardness of the dough. After turning the water, it was put together, chrysanthemum kneading was carried out, and the powder was spread.
For the extension, a pasta machine was used to keep the thickness and thickness of the noodles constant.

The buckwheat (noodle) containing “normal matcha” or “fine powdered matcha” completed in this manner before and after boiling is subjected to a color difference meter (Spectro Co., manufactured by Nippon Denshoku Industries Co., Ltd.).
lorMeter SE2000). Table 4 shows the results.

[0043]

[Table 4]

In the buckwheat dough before boiling, "-b / a
"Value" (the smaller the value, the better the green color, i.e., the better the saturation), but 2% of "fine powdered green tea" showed a better surface color than 4% of "normal matcha". In addition, in the boiled noodles, the difference between “normal matcha” and “fine powdered green tea” tended to be smaller than that of the dough, but “fine powdered green tea” was better than “normal green tea” in “−b / a value”. Excellent surface color was shown (Table 4).

Comparative Example: An attempt was made to produce fine powdered matcha by separating "normal matcha" through a sieve. Separation with a sieve was performed using 100 mesh (aperture: 150 μm) and 200 mesh (aperture: 75 μm). Matcha separated by each sieve was analyzed by a particle size analyzer (Shimadzu Corporation, SALD-210).
(Type 0), the particle size was measured in a dry state. Table 5 shows the results.

[0046]

[Table 5]

Compared with the control, normal matcha,
Those under 100 mesh and under 200 mesh tended to have a slightly smaller median diameter. However, large particles (90
% Cumulative frequency diameter) hardly changed. This can be inferred from the degree of opening of the used sieve. However, under 100 mesh, the yield was about 10 to 15%, and under 200 mesh, only a few% yield was obtained. This is because matcha is a crushed tea plant,
Dietary fibers and the like protrude from the individual particles of matcha, and they become entangled into a so-called "dama" and do not pass through the screen.

[0048]

As described above, the method for producing finely classified tea according to the present invention utilizes the classifying technique, which is a technique for producing a toner for printing, to produce fine pulverized tea which has been difficult until now. Made tea production possible.

Further, the pulverized tea having a small particle size and a limited particle size range obtained by the method of the present invention, when added to food, makes the particles of the pulverized tea difficult to precipitate, has a good texture, and has a good color. Excellent effects such as improvement were achieved, and the adverse effects of the conventional ground tea could be eliminated.

[Brief description of the drawings]

FIG. 1 is a graph showing the particle size distribution of “normal matcha” and “fine powdered matcha”.

FIG. 2 is a graph showing the cumulative distribution of particle sizes of “normal matcha” and “fine powdered matcha”.

FIG. 3 is a graph showing the formation of sedimentation lines of “normal matcha” and “fine powdered matcha”.

FIG. 4 is a graph showing color evaluation results (L values) of “normal matcha” and “fine powdered matcha”.

FIG. 5 is a graph showing the evaluation results (a value) of the colors of “normal matcha” and “fine powdered matcha”.

FIG. 6 is a graph showing color evaluation results (b value) of “normal matcha” and “fine powdered matcha”.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shuichi Takahashi 21 Goddess, Sagara-cho, Haibara-gun, Shizuoka Prefecture F-term (reference) in Itoen Central Research Laboratory Co., Ltd. 4B027 FB06 FC10 FE02 FP68 4B046 LA04 LC08 LG25 4D021 EA02 EB01 4D067 GA13

Claims (4)

[Claims] 1. A method for producing a finely classified tea, comprising a step of pulverizing a tea raw material and a step of classifying the pulverized tea obtained in the step. 2. A finely divided and classified tea obtained by the method according to claim 1. 3. The finely divided classified tea according to claim 2, wherein 90% or more of the total number of particles of the finely divided classified tea has a particle size of 10 μm or less. 4. A food comprising the finely classified tea according to claim 2 or 3.