JP3511164B2 - Tea extract for storage in closed container and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a tea extract stable for long-term storage and a method for producing the same, and more particularly, a tea extract containing a tannin component that does not cause precipitation during long-term storage. And its manufacturing method.

[0002]

2. Description of the Related Art Tea extracts containing tannin components such as black tea, green tea and oolong tea are tea leaves extracted with hot water, and the extracts are filtered, cooled and centrifuged to obtain fine tea leaves. As a tea beverage product for direct drinking packed in cans or PET (PET) containers after removing insoluble components, or as a concentrated stock solution for diluted drinking, it is aseptic in paper containers and BIB (bag-in-box) containers. It is consumed as a product packed in, and a concentrated extract that is frozen in a 20L can or a drum as a raw material.

However, these tea extracts contain caffeine, proteins, and polysaccharides, and the tannins contained therein may change due to temperature changes during heating and storage during production, temperature changes during refrigeration and freezing, and the passage of time. It becomes insoluble with caffeine, proteins, and polysaccharides, causing cohesion and precipitation to visually impair the commercial value, and causes a phenomenon in which the astringency component precipitates and the flavor changes.

Particularly, these phenomena occur in a concentrated tea extract, and the tea extract filled in a drum or the like as a raw material is diluted with a tea extract to remove insoluble matter generated when the beverage is produced. In addition, many steps such as filtration and centrifugation are required, and the yield is reduced by removing the precipitate, and the flavor components are reduced (that is, the balance of the components contained by removing tannin, caffeine, etc.). And the peculiar flavor and astringency are lost).

Further, the occurrence of precipitation not only visually impairs the commercial value such as turbidity or contamination of foreign matter-like solid matter, but also when diluting a concentrated tea extract, it is necessary to dilute a portion with much turbidity and precipitation. The flavor and liquid color may differ between the liquid and the diluted liquid of the other part, or when the tea extract is filled in the container, the precipitate generated blocks the filling outlet and discharges the tea extract. This causes the problem that the filling amount is not constant.

Therefore, as a method for producing a tea extract by controlling the occurrence of precipitation during long-term storage, a cellulase, hemicellulase, and tannase are added to the tea extract.
After the action of xylanase and pectinase, the method of removing the precipitated components by using a cation exchange resin (Japanese Patent Laid-Open No. 154462/1975), or adjusting the acid range by adding ascorbic acid to the tea extract. Then, after cooling this, the resulting precipitated components are removed by centrifugation or the like,
After that, the method in which the pH is adjusted to the neutral range (JP-A-4-311348), the tea extract is adjusted to the acidic range, and after rapid cooling, oxidase and tannase are added and incubated to remove the precipitated components. A method (Japanese Patent Laid-Open No. 7-303450) has been proposed.

[0007]

However, none of the above-mentioned methods alone has the effect of preventing precipitation such as abuse such as heating or freezing and long-term storage during distribution, and particularly, a concentrated solution such as a diluted solution for use in beverages. It was not sufficient as a method to prevent the precipitation of various tea extracts.

[0008] Further, the occurrence of precipitation is not constant because it depends on the quality of the tea leaves as the raw material, the concentration of the tea extract, the storage conditions, etc., and if the precipitation is removed, the flavor and turbidity of the product become uneven. Therefore, the means for removing the precipitate does not solve the problem that the product quality is not stable. The present invention is intended to address such a problem,
The objects could be achieved by completing the invention described below.

[0009]

As a result of earnest research, the present invention has found that the addition of carrageenan to a tea extract can prevent the precipitation from occurring remarkably, and furthermore, the conventional methods such as cooling precipitation removal and tannase treatment. It was found that by combining the techniques, turbidity and precipitation do not occur even under more severe conditions.

That is, according to the present invention, a carrageenan is added to a tea extract containing a tannin component, whereby a protein or a polysaccharide contained in the tea extract is insolubilized by heating or freezing, This will prevent aggregation with tannin during long-term storage. Here, carrageenan is added for the purpose of an action different from physical aggregation and precipitation inhibition of a precipitation component due to addition of a thickener, and therefore, a very small amount without increasing the viscosity of tea extract. Addition of, for example, 0.0005 to 0.3% by weight has a preferable effect. The type of carrageenan is preferably a copper type, and the carrageenan of the copper type is 30 to
Those containing 100% are desirable.

The tea extract in the present invention has a soluble solid content (Bx) concentration of about 0.2 to 18, that is, a straight type that is directly used for beverages or a concentrated type that is diluted and used for beverages. But good.

Further, in order to improve the stability of the present invention, the tea extract is cooled before the addition of carrageenan to remove the resulting turbid components, or tannase is added before the addition of carrageenan. Alternatively, tannase is added before cooling the tea extract, and then the tea extract is cooled to remove the resulting turbid component.

[0013]

EXAMPLES Examples of the present invention will be described below. First,
As Example 1, in order to determine the effect of the addition of carrageenan according to the present invention and the effective concentration of added carrageenan, tea extract liquids with different added concentrations of carrageenan were used to determine whether a precipitate was formed and whether the flavor was good or bad. A carrageenan addition width test for evaluating each item was performed.

The tea extract to be evaluated is 200 g of black tea leaves.
Was extracted with 2 L of hot water at 70 ° C. (Bx3.3, pH
4.9, tannin content 536 mg), to which 0.00
05% by weight, 0.01% by weight, 0.15% by weight, 0.3
Add each carrageenan by weight% and adjust the pH to 6.5 with baking soda.
After adjusting to, adjust the volume to 2L with fresh water, and
Evaluation solutions 1 to 4 were prepared by heating and sterilizing at 30 ° C for 30 seconds, and the evaluation solutions 1 to 4 were also prepared and aseptically filled in a plastic container and stored at 5 ° C for 30 days, and at 30 ° C. Those stored for 30 days were also adjusted. At this time, a tea extract containing no carrageenan was prepared in the same manner as Control Solution 1.

Then, each tea extract prepared as described above was diluted to the same drinking concentration, and each item was evaluated. In addition, regarding the evaluation method, for the good and bad flavors, with particular emphasis on the astringency, the control solution immediately after sterilization is used as a reference (that is, the equivalent is 3), and the evaluation is good. 1, something that is a little good 2,
Scoring was done on a 5-point scale, with 4 being slightly poor and 5 being poor. For the presence or absence of precipitate formation, 20 ml of tea extract liquid at 20 ° C was sampled in a test tube. The sample was allowed to stand for 60 minutes, and the one in which no precipitation occurred was indicated by a circle, the one in which a dispersible precipitate occurred was indicated by a triangle, and the one in which an aggregated insoluble precipitate occurred was indicated by a cross mark. The results are shown in [Table 1].

[0016]

[Table 1]

From the results shown in the above [Table 1], the control liquid 1 had turbidity immediately after sterilization, and turbidity increased during storage and settled. However, in the case of adding carrageenan, the addition concentration was 0.
It was 0005% by weight, and when stored at 5 ° C. for 30 days, almost no turbidity occurred and settled, but almost no insoluble component was generated, and the addition of carrageenan suppressed the generation of turbidity component, resulting in precipitation. It was confirmed that the above-mentioned problems can be prevented and flavors such as astringency can be maintained. Further, the precipitate generated in Control Solution 1 did not dissolve even when diluted with water, and the flavor was worse than before sterilization, with less astringency and worsening astringency.
In the case of carrageenan-added, in Evaluation Solution 4 (addition concentration is 0.3% by weight), precipitation does not occur, but the viscosity of the solution increases and the mixing property at the time of dilution decreases, and Although the flavor was uncomfortable and the palatability was reduced, the other flavors were not particularly uncomfortable, and it was confirmed that the addition of carrageenan did not deteriorate the flavor if attention was paid to the increase in viscosity.

Next, as Example 2, in order to determine whether or not the effect of adding carrageenan due to the difference in the soluble solid content concentration (Bx) of the tea extract solution was determined, tea extract solutions having different soluble solid content concentrations were prepared. A test was conducted based on the difference in the soluble solid content concentration to evaluate each item of whether or not a precipitate was formed and whether the flavor was good or bad.

The tea extract to be evaluated was extracted in the same manner as in Example 1 from 2000 g of black tea leaves with 20 L of hot water at 70 ° C. (B × 3.3, pH 4.9, tannin content 5).
36 mg), to which different soluble solids concentrations were obtained by diluting with fresh water or concentrating with an evaporator, after adjusting the pH to 6.5 with sodium bicarbonate, adding 0.05% by weight of carrageenan, Evaluation solutions 5 to 9 were prepared by heat sterilization at 135 ° C for 30 seconds, and the evaluation solutions 5 to 9 were prepared and aseptically filled in a plastic container and stored at 5 ° C for 30 days, and 30 ° C. 30
I adjusted the ones stored for a day. At this time, a tea extract containing no carrageenan was prepared in the same manner as the control solution 2
And The concentration of soluble solids (Bx) when diluted with fresh water or concentrated with an evaporator was 0.2,
It was 1.5, 3.1, 9.3, and 18.2.

Then, each tea extract prepared as described above was diluted to the same drinking concentration, and the evaluation of each item was carried out by the same evaluation method as in Example 1. The results are shown in [Table 2].

[0021]

[Table 2]

From the results shown in the above [Table 2], the control solution 2 had cloudiness immediately after sterilization and increased and settled during storage.
When carrageenan was added, the evaluation liquid 9 (having a soluble solid content concentration of 18.2 (Bx)) had some turbidity and a decrease in flavor, but this was due to concentration, Evaluation solution 5 to 9 (soluble solid concentration of 0.2 to 1
It was confirmed that even in a wide range of soluble solid content concentration (8.2 (Bx)), the occurrence of turbidity and precipitation during storage was suppressed, precipitation was prevented, and flavor was maintained.

Next, as Example 3, in order to determine whether or not the effect of adding carrageenan when the tea extract was extracted at a drinking concentration from the beginning and was formulated at a low pH, the tea extract was extracted. A test was carried out to evaluate each item, whether or not a precipitate was formed, and whether the flavor was good or bad.

The tea extract to be evaluated was prepared by extracting 20 g of black tea leaves with 2 L of hot water at 80 ° C. (B × 0.4, pH).
5.1, tannin content 54 mg), 0.002% by weight of carrageenan was added to this, pH was adjusted to 5.8 with baking soda, the volume was adjusted to 2 L with fresh water, and sterilized by heating at 135 ° C for 30 seconds. To prepare the evaluation liquid 10 by
In addition, after the evaluation liquid 10 was prepared, it was aseptically filled in a plastic container and stored at 5 ° C for 30 days, and at 30 ° C at 30 ° C.
I adjusted the ones stored for a day. At this time, a tea extract containing no carrageenan was prepared in the same manner as the control solution 3
And

Then, the evaluation of each of the above items for the tea extracts prepared as described above was carried out by the same evaluation method as in Example 1. The results are shown in [Table 3].

[0026]

[Table 3]

From the results shown in the above [Table 3], the turbidity of the control solution 3 was not observed immediately after sterilization, but turbidity occurred during storage and the flavor was deteriorated. It was confirmed that neither turbidity nor precipitation occurred in the inside, and the flavor was astringent and had no change, and the flavor could be prevented and the flavor could be maintained at a wide range of drinking concentrations.

Next, as Example 4, as in Example 3, the tea extract was extracted from the beginning at a drinking concentration, and further,
In order to determine the effect of carrageenan addition when formulating low pH by adding lemon juice and sugar to this, each item of the tea extract was evaluated for the presence or absence of precipitate formation, and whether the flavor was good or bad. The test was done.

The tea extract to be evaluated was prepared by extracting 20 g of black tea leaves with 2 L of hot water at 80 ° C. (B × 0.4, pH).
5.1, tannin content 54 mg), to which 0.5% by weight of lemon juice and 5% by weight of sugar were added and 0.002% by weight of carrageenan was added, and the pH was adjusted to 3.8 with baking soda, and then purified water. Up to 2L with 110 ℃
After being sterilized by heating for 30 seconds, the evaluation liquid 11 is prepared, and the evaluation liquid 11 is aseptically filled in a plastic container after the adjustment and stored at 5 ° C. for 30 days, and at 30 ° C. for 30 days. Also adjusted. At this time, a tea extract containing no carrageenan was prepared in the same manner as a control liquid 4.

Then, the evaluation of each of the above items for the tea extracts prepared as described above was carried out by the same evaluation method as in Example 1. The results are shown in [Table 4].

[0031]

[Table 4]

From the results shown in the above [Table 4], the control solution 4 did not show significant turbidity immediately after sterilization, but turbidity or precipitation occurred during storage, impairing the external appearance and lowering the flavor.
The carrageenan added product did not cause insoluble precipitation not only immediately after sterilization but also during storage, and the flavor was good with no change in astringency, and even if lemon juice or sugar was added, precipitation was prevented and the flavor was maintained. I confirmed that I can do it.

Next, as Example 5, cold centrifugation treatment, that is, treatment in which tea extract is cooled to remove turbid components before addition of carrageenan, and carrageenan addition in combination with carrageenan addition In order to determine the effect of the above, the tea extract was subjected to a test to evaluate each item of the presence or absence of precipitate formation, and whether the flavor was good or bad.

The tea extract to be evaluated is green tea leaves 2500
g was extracted with 20 L of hot water at 70 ° C. (B × 3.1,
pH 5.4, tannin content 583 mg), this at 5 ℃
After cooling, the turbid component was removed by centrifugation, sodium ascorbate was added by 0.3% by weight, carrageenan was added by 0.05% by weight, and the pH was adjusted to 6.2 with sodium bicarbonate, and the volume was adjusted to 20 L with fresh water. 30 up at 135 ℃
It is adjusted by sterilizing by heating for 2 seconds to give the evaluation liquid 12, and the evaluation liquid 12 is adjusted and then aseptically filled in a BIB (bag-in-box) container and stored at 5 ° C. for 30 days.
And that stored at 30 ° C. for 30 days were also adjusted. On this occasion,
A tea extract that was cooled and centrifuged but carrageenan was not added was prepared by the same procedure as Control Liquid 5, and a tea extract that was added to carrageenan without cooling and centrifugation was prepared by the same procedure. This was used as control solution 6, and a tea extract prepared by neither cooling and centrifugation nor addition of carrageenan was prepared by the same operation as control solution 7.

Then, the evaluation of each of the above-mentioned items for the tea extract prepared as described above was carried out by the same evaluation method as in Example 1. The results are shown in [Table 5].

[0036]

[Table 5]

From the results shown in the above [Table 5], although the control solutions 5 and 7 to which carrageenan was not added showed no noticeable turbidity immediately after sterilization, turbidity or precipitation occurred during storage, impairing the appearance and deteriorating the flavor. However, the one to which carrageenan was added did not cause turbidity or precipitation during storage as well as immediately after sterilization, and the flavor had no change in astringency and was good, and further, cooling centrifugal treatment and addition of carrageenan were used together. That is, the one in which carrageenan was added after cooling the tea extract after hot water extraction to remove turbid components, did not cause turbidity or precipitation, and the flavor was good with no change in astringency. Of course, it was confirmed that the stability against long-term storage was enhanced as compared with the case where only carrageenan was added.

Next, as Example 6, tannase treatment and cold centrifugation treatment, that is, treatment in which tannase was added before addition of carrageenan and then the tea extract was cooled to remove turbid components. In order to determine the effect of carrageenan addition when using carrageenan addition together,
The tea extract was subjected to a test to evaluate each item of whether or not a precipitate was formed and whether or not the flavor was good or bad.

As the tea extract to be evaluated, 2500 g of green tea leaf was extracted with 20 L of hot water at 70 ° C. (B × 3.1, pH 5.4, tannin content 583) as in Example 5.
mg), to which 0.02% by weight of tannase was added to obtain 35
Enzymatic treatment at 90 ℃ for 90 minutes, then cooling to 5 ℃ and centrifuging to remove turbidity. After adding 0.3% by weight of sodium ascorbate, add 0.05% by weight of carrageenan and add sodium bicarbonate to adjust pH. After adjusting to 6.2, 2 with fresh water
The test solution is adjusted to 0 L and sterilized by heating at 135 ° C. for 30 seconds to give the evaluation liquid 13, and the evaluation liquid 13 is also aseptically filled in a BIB (bag-in-box) container after adjustment, and the temperature is 5 ° C. Those stored at 30 ° C. for 30 days and those stored at 30 ° C. for 30 days were also adjusted. At this time, a tea extract containing no carrageenan was prepared in the same manner as a control liquid 8.

Then, the evaluation of each of the above items for the tea extracts prepared as described above was carried out by the same evaluation method as in Example 1. The results are shown in [Table 6].

[0041]

[Table 6]

From the results shown in the above [Table 6], although the control solution 8 did not show significant turbidity immediately after sterilization, it had turbidity or precipitation during storage, which impaired the appearance and deteriorated the flavor.
A combination of tannase treatment, cooling centrifugal treatment, and carrageenan addition, that is, tannase was added to the tea extract after hot water extraction to perform enzyme treatment, and then cooled to remove turbid components, and carrageenan was added. Not only immediately after sterilization, turbidity and precipitation did not occur during storage, but the flavor was astringent and the taste was good, and the stability against long-term storage was also good without cooling with tannase treatment. Combination of addition, that is, Example 6 above
It was confirmed that it was higher than that of the evaluation liquid 12 in the above.

Further, as Example 7, in order to determine the effect of adding carrageenan when the tea extract was concentrated and the extract was concentrated, the tea extract was examined for the presence or absence of precipitate formation and the flavor. A test was conducted to evaluate each item.

The tea extracts to be evaluated are oolong tea leaves 2
The extract obtained by extracting 00 g with 2 L of hot water at 90 ° C. was concentrated by an evaporator (Bx11.5, pH 4.9, tannin content 1260 mg), and 0.1 g of carrageenan was added thereto.
Add 0% by weight and adjust the pH to 6.5 with baking soda to give the evaluation liquid 14. At the same time, after adjusting the evaluation liquid 14, the can container is hot-packed at 90 ° C., and then at 5 ° C. for 30 days. Those stored and those frozen and stored for 30 days were also prepared. At this time, a tea extract containing no carrageenan was prepared in the same manner as a control liquid 9.

Then, the evaluation of each of the above items for the tea extracts prepared as described above was performed by the same evaluation method as in Example 1. The results are shown in [Table 7].

[0046]

[Table 7]

From the results shown in the above [Table 7], the concentrated control liquid 9 was apt to cause precipitation, and particularly when the frozen solution was thawed, a very large amount of precipitation was generated and the flavor was large. Although it decreased, the one to which carrageenan was added showed little turbidity or precipitation not only immediately after sterilization but also during storage.
It was confirmed that the flavor was good with no change in astringency, and even if the tea extraction target changed, it was possible to prevent precipitation and maintain the flavor.

[0048]

As described above, according to the present invention, by adding carrageenan to the tea extract, insolubilization of proteins and polysaccharides contained in the tea extract by heating and freezing, long-term storage, etc. Since the occurrence of precipitation due to aggregation with the tannin is prevented, it can be made to have excellent flavor and visually high commercial value.

In addition, by adding carrageenan together with conventional techniques such as cooling precipitation removal and tannase treatment, the stability for long-term storage can be further enhanced.

Further, according to the present invention, since the precipitation is prevented from occurring, many steps such as filtration and centrifugal treatment for removing the generated insoluble matter are unnecessary, and the precipitation is removed. There is no fear that the yield or flavor component will decrease.

Further, according to the present invention, when a concentrated tea extract is diluted for drinking, there is no fear that the flavor or liquid color will vary depending on the diluted liquid and the product quality will become unstable.

Further, according to the present invention, when the tea extract liquid is filled in the container, the generated precipitates block the liquid outlet and hinder the discharge of the tea extract liquid, causing a problem that the filling amount is not constant. There is no fear of it.

Continuation of the front page (56) Reference JP-A-9-154490 (JP, A) JP-A-3-39043 (JP, A) JP-A-8-174 (JP, A) JP-A-5-244868 (JP , A) JP 50-154462 (JP, A) JP 7-303450 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) A23K 3/00

Claims (2)

(57) [Claims] 1. Free of calcium carbonate and milk protein
The tea extract containing tannin in at least 3
Carrage consisting of 0-100% copper carrageenan
-0.005 wt% or more and 0.3 wt% or less
The soluble solid content of the extract has a Bx concentration of 0.2 to 1
8. A tea extract for preservation in a closed container, which is 8. 2. Free of calcium carbonate and milk protein
Tannase is added to the tea extract containing tannin
After adding and removing the turbid component, at least 30% or more
Carrageenan consisting of the above copper carrageenan
Added 0.0005 wt% or more to 0.3 wt% or less
Extraction of teas for storage in closed containers characterized by being an extract
Liquid manufacturing method.