JP2003000208A - Method for preventing guava tea drink from causing precipitation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for preventing a guava tea drink from causing precipitation, suppressing the generation of the precipitation and enabling long preservation without lowering the effectiveness of guava tea, and also to provide the guava tea drink with high commercial value produced by using the method. SOLUTION: This method for preventing the guava tea drink from causing the precipitation is characterized by subjecting a guava leaf extracted solution as the raw material for producing the drink to microfiltration with a filter having a reserved particle diameter of <=5 μm, The guava tea drink prevented from causing precipitation through the method is also provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing precipitation of guava leaf extract and a beverage having good long-term storage stability, which uses the guava leaf extract whose precipitation is prevented by this method.

[0002]

BACKGROUND ART In recent years, it has been confirmed that a substance having an α-amylase inhibitory activity is contained in guava leaves, and its α-amylase inhibitory action is caused by a unique guava leaf polyphenol contained in guava leaves. It has become clear that it is a thing.

Therefore, there is an increasing demand for guava leaf extract (hereinafter referred to as "guava tea") as a health food,
Many studies have been conducted on them (Patent 297).
4946, etc.). And recently, a beverage containing guava tea (hereinafter referred to as "guava tea beverage") is commercially available. However, there is a problem that a beverage containing guava tea may cause precipitation when the product is stored for a long period of time, and the appearance is impaired by the occurrence of the precipitation.

By the way, it is widely known that white tea and green tea beverages also have cloudiness and precipitation during production or during long-term storage, and this phenomenon is called cream down or creaming. In order to suppress this phenomenon, various cream down suppression methods have been reported, such as centrifugation, diatomaceous earth filtration, polyphenol adsorption by polyphenol adsorption resin, decomposition of tannin by tannase treatment, addition of inorganic salts such as calcium.

[0005]

However, it has been substantially difficult to apply the cream-down suppressing method applied to black tea beverages and green tea beverages to guava tea beverages. For example, precipitation with time could not be suppressed by centrifugation, addition of an inorganic salt, or decomposition of tannin by tannase treatment. In addition, diatomaceous earth filtration and filtration with a polyphenol-adsorbing resin reduced the amount of guava leaf polyphenol, which is an active ingredient of guava tea, regardless of the effect of preventing precipitation. As described above, it was difficult to suppress the occurrence of precipitation during long-term storage while maintaining the effectiveness of guava tea.

[0006] Therefore, the present invention has found a method of suppressing the occurrence of precipitation and enabling long-term storage without lowering the effectiveness of guava tea, and a guava having a high commercial value manufactured by using the method. It is intended to provide tea beverages.

[0007]

As a result of research to solve the above-mentioned problems, the present inventors have found that the main component of the precipitate of guava tea beverage is ellagic acid, which is a kind of polyphenol. Then, the process of precipitation from ellagic acid was estimated as follows. That is, ellagic acid is present alone in guava leaf, but since it is also a constituent component of guava leaf polyphenol, some ellagic acid is dissociated from guava leaf polyphenol over time. Then, in the guava tea beverage, the ellagic acid present alone in the guava tea aggregates into a crystal nucleus, and the ellagic acid liberated from the guava tea polyphenol is precipitated in this nucleus,
It was presumed that large crystals formed with time and precipitated.

Therefore, if the fine crystal nuclei of free ellagic acid that are floating and present during the production of guava tea are removed,
It is considered that the crystal nuclei do not exist, the generation of precipitation is delayed, and the amount of precipitation can be reduced. As a result of various studies based on this idea, when guava tea is microfiltered with a filter having a certain retention particle size, it is possible to remove free ellagic acid that becomes a crystal nucleus, and as a result, the occurrence of precipitation is suppressed. , And by this method, the inventors have found that the α-amylase inhibitory activity of guava tea does not decrease, and have completed the present invention.

That is, according to the present invention, in producing a guava tea beverage using a guava leaf extract as a raw material, the guava leaf extract is microfiltered with a filter having a reserved particle size of 5 μm or less to prevent the precipitation of guava tea. It provides a method.

In addition, according to the present invention, in producing a guava tea beverage using a guava leaf extract as a raw material, the guava leaf extract is cooled to 20 ° C. or lower and then filtered to prevent precipitation of the guava tea beverage. It provides a method.

Furthermore, the present invention provides a guava tea beverage, the precipitation of which is prevented by the above method.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, guava tea refers to an extract obtained by extracting guava leaves with an extraction solvent such as water (hot water) at 50 ° C. or higher.

The guava leaf, which is a raw material for preparing the guava tea, is not particularly limited in its production area and the like. It is preferable to use shredded pieces of various sizes, and in particular, to improve the flavor of guava tea, it is preferable to use shredded guava leaves that have been roasted.

The guava leaf extraction conditions for preparing this guava tea are not particularly limited, but at a temperature of 50 ° C. to 100 ° C., preferably 80 ° C. to 100 ° C., 1 minute to 60 minutes, preferably 3 minutes to. It is good to extract for 25 minutes. If the extraction temperature of guava tea is too high, the flavor becomes poor, and if it is too low, the active ingredient is not extracted. On the other hand, if the extraction time is too long, the flavor becomes poor, and if it is too short, the active ingredient is not extracted. In addition, the ratio of guava leaves to the extraction solvent is 1:10 by weight.
1:30 is preferable. If the ratio of guava leaves is too large, the flavor becomes poor, and if it is too small, the active ingredient is not extracted. Further, the pH may be adjusted by adding an alkaline substance such as sodium bicarbonate to water which is an extraction solvent.

To carry out the method of the present invention, the guava tea obtained as described above is microfiltered with a filter having a retained particle size of 5 μm or less (with a rated filtration accuracy of 99.98%). As the filter, it is particularly preferable to use a filter having a retained particle size of 1.5 μm or less (with a rated filtration accuracy of 99.98%). Further, it is preferable to use a filter having not only the mechanical filtration action but also the adsorption action by the zeta potential. By performing such microfiltration, it is possible to highly remove ellagic acid (crystals) in guava tea, and it is possible to suppress the precipitation that occurs when the guava tea beverage containing guava tea is stored for a long period of time. Become.

In the method of the present invention, the guava leaf extract immediately after extracting the guava leaves is cooled to 20 ° C. or lower,
Then, by filtering this, it is possible to suppress the occurrence of precipitation during long-term storage of the guava tea beverage. The cooling method is not particularly limited, and a commonly used method such as cooling with a heat exchange plate or a jacketed tank may be used. The filtration may be microfiltration using the above-mentioned filter or normal filtration using a filter paper or the like. In particular,
If a cooling step is provided as a step before the microfiltration, the ability to remove ellagic acid (crystals) by filtration is enhanced, and as a result, an excellent effect of preventing the precipitation of guava tea beverage is achieved, which is preferable.

Furthermore, in order to enhance the effect of suppressing the occurrence of precipitation of the guava tea beverage containing guava tea after microfiltration during long-term storage, it is preferable to cool the guava tea beverage to 40 ° C. or lower after production. It is particularly preferable to cool to 25 ° C or lower. The cooling method is not particularly limited, and a commonly used method such as showering a container after filling may be used.

Further, it is preferable to remove coarse impurities in guava tea by centrifugation or the like as a pre-step of microfiltration as in the cooling step. By performing this step, clogging of the filter during the next microfiltration can be reduced, and the filter can be used as long as possible.

When the guava tea thus obtained is used as a guava tea beverage product, it may be used as it is, or may be concentrated or diluted to an appropriate concentration. The solid content concentration in the extract is such that the content of tannin contained in the solid content is about 0.05% to 0.1% in terms of flavor and effectiveness (blood sugar level due to α-amylase inhibition. The effect of suppressing) is preferable. Microfiltration may be used for concentrating guava tea, or may be used either before or after concentration or dilution.

Further, in order to improve the flavor of guava tea, it is preferable to add an extract of berries, which is a young fruit of guava. Furthermore, it is preferable to add vitamin C in order to improve the flavor of guava tea and suppress the decrease in α-amylase inhibitory activity. Japanese Patent No. 2974946 describes adding berry extract and vitamin C to guava tea.

The guava tea beverage of the present invention can be manufactured specifically as follows. First, after drying the guava leaves, cut them into 5 mm pieces, roast them at 250 ° C. for 15 minutes, and then
Guava tea is obtained by extraction with hot water at 98 ° C. for 5 minutes. The obtained guava tea is centrifuged with a centrifuge and then microfiltered with a filter having a retained particle size of 5 μm or less.
After heating to 0 ℃, transparent containers such as PET bottles, paper containers,
It is filled in a can container or the like, and post-sterilized depending on the container form to obtain a guava tea beverage.

When producing guava tea beverages, various sugars, emulsifiers, thickeners, sweeteners, acidulants, fruit juices and the like can be appropriately added as auxiliary materials, if necessary.
Specifically, sucrose, isomerized sugar, glucose, fructose, palatinose, trehalose, lactose, sugars such as xylose, acesulfame potassium, stevia, aspartame, high-potency sweeteners such as alitame, sorbitol, xylitol, erythritol, lactitol, Sugar alcohols such as palatinit, reduced starch syrup, reduced maltose starch syrup, sucrose fatty acid ester, glycerin fatty acid ester, emulsifier such as lecithin, carrageenan, gum arabic, xanthan gum, guar gum, pectin, locust bean gum, starch, gellan gum and other thickening agents (Stabilizer), acidulants such as citric acid, lactic acid, malic acid, tartaric acid, plum juice, apple juice, lemon juice, orange juice,
Examples thereof include fruit juice such as berry fruit juice and flavors thereof.
In addition to this, vitamin A, vitamin B, vitamin C,
Vitamins such as vitamin D and vitamin E, calcium,
It is possible to add minerals such as iron, manganese and zinc. There is no particular limitation on the order of addition when adding these food materials.

[0023]

The reason why the microfiltration of the method of the present invention suppresses the occurrence of precipitation when the guava tea beverage is stored for a long time is not always clear, but it is considered as follows at present. That is, in the formation of the precipitate, free ellagic acid originally contained in guava tea and agglomerates generated by agglomeration of free ellagic acid dissociated from guava tea polyphenol as a main component are involved. There is. When these ellagic acids are deposited as crystals, it is considered that fine crystals serving as nuclei are present. Therefore, it is considered that the subsequent precipitation is suppressed by removing the free ellagic acid and other substances originally contained in guava tea from the beginning, which may be the fine crystal nuclei, by microfiltration.

By adopting microfiltration using a filter having a retained particle size of 5 μm or less, the amount of polyphenols having α-amylase inhibitory activity is not reduced, and therefore, the effectiveness of the polyphenols at the time of storage can be maintained without impairing the effectiveness. It is considered that guava tea in which the occurrence of the precipitate of (1) is suppressed can be obtained.

[0025]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

Test Example 1 Analysis of Precipitated Components of Guava Tea Beverage: Guava leaves (produced in Guangxi, China) were dried and roasted at 250 ° C. for 15 minutes, and then 5 mm
Shred to a degree. 125 g of this tea leaf is heated to 98 ° C. 2.
It was placed in 5 kg and extracted for 5 minutes to obtain guava tea. The guava tea was cooled to 20 ° C. or lower, centrifuged using a continuous centrifuge to remove coarse impurities, and then filtered using a normal filter paper (holding particle size: about 20 μm). The guava tea after microfiltration was diluted with water so that the tannin content was 0.08% to obtain a final guava tea. The guava tea was heated to 90 ° C. to sterilize, filled in a 500 mL PET bottle, and then cooled to 40 ° C. or lower to produce a guava tea beverage.

The guava tea beverage produced as described above was stored at room temperature for 1 year, and the main component of the resulting precipitate was analyzed by the following method. The guava tea beverage precipitate was collected by centrifugation and dried in a vacuum desiccator. This was rolled by a micro compression cell under a stereoscopic microscope to obtain an analytical sample. The infrared absorption spectrum of this analysis sample was measured by infrared absorption spectrum measuring instrument FTS-65A and UMA3.
00A (both manufactured by Bio-Rad digilab). The measurement uses MCT as a detector,
Resolution 8 cm- ¹ , integration count 256 times, measurement range 400
0~900cm ^- it was carried out in ^one of the conditions. Further, since it is a measurement of a minute area, three different locations of the sample were similarly measured to confirm the uniformity of the sample. Further, a commercially available ellagic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) was used as a standard product, and the infrared absorption spectrum was measured in the same manner. The measurement results are shown in FIG.

As is clear from FIG. 1, the precipitation of guava tea beverage and the infrared absorption spectrum of ellagic acid were in agreement, and it was confirmed that the main component of the precipitation of guava tea beverage was ellagic acid.

Example 1 Production of Guava Tea Beverage (1): Guava leaf (produced in Guangxi, China) was dried and roasted at 250 ° C. for 15 minutes, then 5 mm
Shred to a degree. 75 kg of this tea leaf is heated with 98 ° C. hot water 15
It was put in 00 kg and extracted for 5 minutes to obtain guava tea. This guava tea was cooled to 20 ° C. or lower with a heat exchange plate and centrifuged using a continuous centrifuge to remove coarse impurities. This guava tea is then retained particle size 1.5μ
Microfiltration was carried out using a filter of m (rated filtration accuracy of 99.98%). The guava tea after microfiltration was diluted with water so that the amount of tannin was 0.08% to obtain a final guava tea. Sterilize by heating this guava tea to 90 ° C or higher,
After filling a plastic bottle with a capacity of 500 mL, it was cooled to 40 ° C. or lower by a shower ring to produce a guava tea beverage. In addition, as Comparative Example 1, a guava tea beverage was produced in exactly the same manner as in Example 1 except that microfiltration was not performed.

Analysis of Guava Tea Beverages: Example 1 and Comparative Example 1
The amount of guava leaf polyphenol and the α-amylase inhibitory activity of the guava tea beverage obtained in 1. were quantified.

(1) Determination of Polyphenol in Guava Tea Beverage The amount of guava leaf polyphenol was determined by the following method. 10 mL of each beverage was taken and insoluble matter was filtered to obtain a sample solution.
Separately, 2 mg of guava tea polyphenol standard product (manufactured by Yakult Honsha Co., Ltd.) was precisely weighed and dissolved in 1 mL of water to obtain a standard solution. Quantitation of guava tea polyphenol in each sample solution and standard solution was performed by the HPLC method. An ultraviolet absorptiometer (measurement wavelength: 260 nm) was used as a HPLC detector, and acetonitrile was used as a mobile phase, 0.01 mol / L NaH ₂ PO ₄ aqueous solution, and 0.01 mol / L Na ₃ PO ₄ aqueous solution. Was measured by the step gradient method. The amount of guava tea polyphenol was calculated by the following formula 1.

[0032]

[Formula 1]

(2) Measurement of α-amylase inhibitory activity The α-amylase inhibitory activity was measured by the following method. To 0.5 mL of 8% soluble starch solution (prepared by dissolving starch in 0.08 mol / L phosphate buffer), each sample obtained in the same manner as in (1) above and water as a control were added. 1.5 mL of each was added, and the mixture was kept warm at 37 ° C. 0.02 mL of α-amylase solution preheated to 37 ° C
(The titer was adjusted to be constant with 0.02 mol / mL phosphate buffer) was added, and the mixture was reacted at 37 ° C. Then, the reaction was terminated by heating in boiling water to inactivate the enzyme.
Maltose produced in this reaction was quantified by an HPLC method using arabinose as an internal standard. The HPLC detector used a differential refractometer, and the mobile phase used water. After quantifying the amount of maltose, the α-amylase inhibitory activity of the sample was calculated by the following formula 2.

[0034]

[Formula 2]

The amount of guava leaf polyphenol in the guava tea beverage and the result of the α-amylase inhibitory activity measurement are shown in Table 1 together.

[0036]

[Table 1]

As is clear from Table 1, the amount of guava leaf polyphenol and the α-amylase inhibitory activity of Example 1 were almost the same as those of Comparative Example 1. Therefore, it was found that the active ingredient was not removed even when guava tea was microfiltered using a filter having a retained particle size of 1.5 μm.

(3) Measurement of Precipitated Amount The guava tea beverages obtained in Example 1 and Comparative Example 1 were stored at 37 ° C. for 3 months, and the time and amount of precipitation were examined. The amount of precipitation was evaluated according to the following evaluation criteria. The results are shown in Table 2.

[0039]

[0040]

[Table 2]

As is clear from Table 2, in Example 1, the occurrence of precipitation was delayed by 1 to 2 months and the amount of precipitation was small as compared with Comparative Example 1.

From the above results, the guava tea beverage containing guava tea that has been microfiltered has no active ingredient, and the occurrence of precipitation is delayed even when compared to the guava tea beverage that contains guava tea that has not been microfiltered. Therefore, it was shown that long-term storage is possible.

Example 2 Production of Guava Tea Beverage (2): Guava leaf (produced in Guangxi, China) was dried and roasted at 250 ° C. for 15 minutes, and then 5 mm.
Shred to a degree. 125 g of this tea leaf is heated to 98 ° C. 2.
It was placed in 5 kg and extracted for 5 minutes to obtain guava tea. This guava tea was cooled to 20 ° C. or lower with a heat exchange plate, centrifuged using a continuous centrifuge to remove coarse impurities, and then filtered using normal filter paper (retained particle size 20 μm). . Guava tea after filtration has a tannin content of 0.08
The final guava tea was obtained by diluting by adding water so that the amount of the guava tea was 100%. This guava tea is heated to 90 ° C and sterilized, and then 50
After filling a 0 mL PET bottle, it was cooled to 40 ° C. or lower to produce a guava tea beverage. Also, as Comparative Example 2, a guava tea beverage was produced in exactly the same manner as in Example 2 except that the guava tea was not cooled after extraction and was centrifuged and filtered at around 80 ° C.

The guava tea beverages obtained in Example 2 and Comparative Example 2 were stored at 55 ° C. for 1 month, and the amount of precipitation was examined and evaluated in the same manner as in Example 1. The results are shown in Table 3.

[0045]

[Table 3]

As is clear from Table 3, the amount of precipitation in Example 2 was smaller than that in Comparative Example 2. From this, it was shown that the generation of precipitation can also be suppressed by cooling the guava tea before filtration.

Example 3 Production of Guava Tea Beverage (3): Guava leaf (produced in Guangxi, China) was dried and roasted at 250 ° C. for 15 minutes, and then 5 mm.
Shred to a degree. 125 g of this tea leaf is heated to 98 ° C. 2.
It was placed in 5 kg and extracted for 5 minutes to obtain guava tea. This guava tea was cooled to 20 ° C. or lower with a heat exchange plate, centrifuged using a continuous centrifuge to remove coarse impurities, and then retained particle size of 1.5 μm (Example 3), 5 μm.
m (Example 4) and 10 μm (Comparative Example 3) membrane filters were used for microfiltration. The guava tea after microfiltration was diluted with water so that the tannin content was 0.08% to obtain a final guava tea. The guava tea was heated to 90 ° C. to sterilize, filled in a 500 mL PET bottle, and then cooled to 40 ° C. or lower to produce a guava tea beverage.

The guava tea beverages obtained in Examples 3, 4 and Comparative Example 3 were stored at 55 ° C. for 1 month, and the amount of precipitation was examined and evaluated in the same manner as in Example 1. The results are shown in Table 4.

[0049]

[Table 4]

As is clear from Table 4, the retained particle diameter is 5 μm.
The amount of precipitation of Example 3 using the filter of m was smaller than that of Comparative Example 3 using the filter of retained particle size of 10 μm, and precipitation occurred in Example 4 using the filter of retained particle size of 1.5 μm. There wasn't. This indicated that a filter with a specific retention particle size had to be used to remove ellagic acid in guava tea.

Example 4 Evaluation of Amount of Precipitation of Guava Tea Beverage and Green Tea Beverage: As Comparative Example 4, a green tea beverage was produced in exactly the same manner as Example 4 except that green tea was used in place of the guava tea of Example 4. . The guava tea beverage obtained in Example 4 and the green tea beverage obtained in Comparative Example 4 were stored at 55 ° C. for 1 month, the amount of precipitation was examined, and evaluated in the same manner as in Example 1. The results are shown in Table 5.

[0052]

[Table 5]

As is clear from Table 5, precipitation occurred in Comparative Example 4 and no precipitation occurred in Example 4. From this, it is possible to suppress the occurrence of precipitation when producing a guava tea beverage using microfiltered guava tea, but it is possible to suppress the occurrence of precipitation even when producing a green tea beverage using microfiltered green tea. I showed that I can't. Therefore, it can be said that the effect of suppressing the generation of precipitate by microfiltration is peculiar to guava tea.

[0054]

EFFECTS OF THE INVENTION The guava tea beverage of the present invention has the same effectiveness as that of a normal guava tea beverage and suppresses the occurrence of precipitation for a long period of time, and thus can be widely used as a long-term storable health beverage.

[Brief description of drawings]

FIG. 1 is a drawing showing an infrared absorption spectrum of guava tea beverage precipitate and ellagic acid. that's all

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Katsutoshi Harada             1-1-19 Higashishimbashi, Minato-ku, Tokyo Stock market             Company Yakult Head Office (72) Inventor Takashi Makino             1-1-19 Higashishimbashi, Minato-ku, Tokyo Stock market             Company Yakult Head Office (72) Inventor Kuniko Nagata             1-1-19 Higashishimbashi, Minato-ku, Tokyo Stock market             Company Yakult Head Office (72) Inventor Yoriko Deguchi             1-1-19 Higashishimbashi, Minato-ku, Tokyo Stock market             Company Yakult Head Office (72) Inventor Ritsuo Aiyama             1-1-19 Higashishimbashi, Minato-ku, Tokyo Stock market             Company Yakult Head Office (72) Inventor Mako Nakazawa             1-1-19 Higashishimbashi, Minato-ku, Tokyo Stock market             Company Yakult Head Office F-term (reference) 4B017 LC07 LE10 LG15 LP01 LP14

Claims (7)

[Claims] 1. A method of producing a guava tea beverage using a guava leaf extract as a raw material, wherein the guava leaf extract is retained with a particle size of 5
A method for preventing the precipitation of guava tea beverage, which comprises performing microfiltration with a filter having a size of μm or less. 2. The method for preventing precipitation of a guava tea beverage according to claim 1, wherein the guava leaf extract is hot water extracted from guava leaves. 3. Hot water extraction at a temperature of 50 ° C. to 100 ° C.
The method for preventing precipitation of a guava tea beverage according to claim 2, which is carried out for 5 to 60 minutes. 4. The guava leaf extract is cooled to 20 ° C. or lower before microfiltration with a filter having a retained particle diameter of 5 μm or less, and the guava leaf extract is cooled to 20 ° C. or less. Method for preventing sedimentation of guava tea beverages in Japan. 5. The method for preventing precipitation of a guava tea beverage according to any one of claims 1 to 4, which removes ellagic acid in the guava leaf extract. 6. A method for preventing the precipitation of a guava tea beverage, which comprises cooling the guava leaf extract to 20 ° C. or lower and then filtering the guava tea beverage using the guava leaf extract as a raw material. 7. A guava tea beverage that has been prevented from settling by the method according to any one of claims 1 to 6.