AU2015365199B2

AU2015365199B2 - Packaged green tea beverage

Info

Publication number: AU2015365199B2
Application number: AU2015365199A
Authority: AU
Inventors: Miki Sato; Wataru Yamaguchi
Original assignee: Asahi Soft Drinks Co Ltd; Asahi Group Holdings Ltd
Current assignee: Asahi Soft Drinks Co Ltd; Asahi Group Holdings Ltd
Priority date: 2014-12-16
Filing date: 2015-08-20
Publication date: 2019-06-13
Anticipated expiration: 2035-08-20
Also published as: AU2015365199A1; AU2015365199A8; JP6478099B2; WO2016098388A1; JP2016111970A; MY181393A

Abstract

The present invention provides: a low-caffeine packaged green tea beverage having improved taste, aroma, and palatability; and a production method therefor. As a result of adding dimethyl sulfide, the reduction in the taste and aroma of a packaged green tea beverage caused by reducing the caffeine therein can be improved, and palatability can be improved.

Description

Specification

Title of Invention:

PACKAGED GREEN TEA BEVERAGE

Technical Field

The present invention relates to a packaged green tea beverage or a producing method thereof. Particularly, the present invention relates to a packaged, low-caffeine green tea beverage, in which taste and flavor are improved and preference is enhanced, or a producing method thereof.

Background Art

Green tea is a beverage having been favorably drunk by many people through the ages. In addition to the aspect of extraction from tea leaves at home, in restaurants, or other places, green tea is widely prevalent as beverages filled in containers such as plastic bottles, cartons, cans, and glass bottles .

Efforts have been made to analyze ingredients contained in green tea. For example, Non Patent Literature 1 states that higher-grade teas contain relatively a lot of flavor ingredients such as dimethyl sulfide. However, dimethyl sulfide is just one of many flavor ingredients, and Non Patent Literature 1 does not describe a relation between the dimethyl sulfide and preference for the green tea. Also, Non Patent Literature 2 states that the dimethyl sulfide concentration appropriate for ready-to-drink beverages is 0.05%, but has no descriptions regarding green tea and preference. Further, Patent Literature 1 describes a packaged green tea beverage containing dimethyl sulfide, caffeine, a tannin, and the like in a certain ratio, but does not describe beverages obtained by using tea leaves or tea extracts which have been subjected to a caffeine reduction treatment. Additionally, Patent Literature 2 describes a green tea leaf extract having low contents of polyphenol and caffeine, but does not describe dimethyl sulfide.

Prior Art References

Patent Literatures

Patent Literature 1: Japanese Patent Publication No. 2007-110990

Patent Literature 2: Japanese Patent Publication No . 2005-27554 Non Patent Literatures

Non Patent Literature 1: Koryo (flavor and fragrance) (2005), No. 227, pp. 81-91

Non Patent Literature 2 : Perfum. Flavorist (2011), Vol. 36, pp. 18-19

Summary of Invention

Technical Problems

When low-caffeine green tea beverages are produced, low-caffeine green tea materials (for example, a tea leaf powder or a tea concentrate subjected to a caffeine reduction treatment through an ion-exchange resin or activated-carbon treatment) are generally used. For example, extraction of tea leaves with hot water is not performed, and instead low-caffeine green tea powder like instant green tea is dissolved in water to produce the low-caffeine green tea beverages. However, due to the properties of such a material, not only the caffeine concentration but also the catechin concentration would inevitably become low. This results in problems that the taste as a flavor becomes weak, and the preference is decreased. Meanwhile, dimethyl sulfide has been known as just one of many flavor ingredients as described above. Any influence of such dimethyl sulfide on the taste, flavor, and preference of green tea beverages, where concentrations of caffeine and catechin are low, has not been known.

An object of the present invention is to provide a packaged, low-caffeine green tea beverage, in which taste and flavor are improved and preference is enhanced, or a producing method thereof .

Solution to Problems

To solve the above-described problems, the present inventors have conducted intensive studies. As a result, the inventors have found out that dimethyl sulfide (having an aonori (blue seaweed)-like flavor) improves the reduced taste and flavor of the packaged green tea beverage, which are caused by caffeine-reducing treatment, and enhances the preference for the beverage. This finding has led to the completion of the present invention.

Specifically, the present invention provides a packaged green tea beverage or a producing method thereof as described below.

[1] A packaged green tea beverage comprising:

ppm or less of caffeine;

100 ppm or more of a non-polymeric catechin; and

0.05 ppm or more and 1.00 ppm or less of dimethyl sulfide .

[2] The packaged green tea beverage according to [1], comprising a tea leaf powder subjected to a caffeine reduction treatment.

[3] The packaged green tea beverage according to [1] or [2] , comprising a tea concentrate subjected to a caffeine reduction treatment.

[4] The packaged green tea beverage according to any one of [1] to [3] , which is produced by a method not comprising a step of brewing a green tea beverage directly from a tea leaf.

[5] A method for producing a packaged green tea beverage, comprising a step of preparing a solution containing 50 ppm or less of caffeine, 100 ppm or more of a non-polymeric catechin, and 0.05 or more and 1.00 ppm or less of dimethyl sulfide, wherein the method does not comprise a step of brewing a green tea beverage directly from a tea leaf.

[6] The method for producing a packaged green tea beverage according to [5] , further comprising a step of adding a tea leaf powder and/or a tea concentrate which have been subjected to a caffeine reduction treatment.

Advantageous Effects of Invention

According to the present invention, addition of dimethyl sulfide to green tea, where concentrations of caffeine and catechin are low, can improve the taste and flavor of the green tea, and enhance the preference therefor. Thus, addition of dimethyl sulfide can improve the reduced taste and flavor of the packaged green tea beverage, which are caused by caffeine-reducing treatment, and enhance the preference.

Also, since a highly preferable packaged green tea beverage can be produced according to the present invention by the method not including the step of brewing a green tea beverage directly from a raw-material tea leaf, it is possible to shorten the time required for production of a packaged green tea beverage, and to reduce waste materials in a production factory, in comparison with a producing method comprising the step of brewing a green tea beverage directly from a raw-material tea leaf .

Description of Embodiments

As a raw-material tea leaf for the green tea beverage described herein, tea leaves used in this technical field can be used without limitation. For example, tea leaves of non-fermented teas such as steamed tea, sencha, gyokuro, matcha, bancha, tamaryokucha, kamairicha, and Chinese green tea may be used, or a blend of two or more of these tea leaves may be used. The raw-material tea leaf can be used in the form of tea leaf powder obtained by powderization, or in the form of tea concentrate obtained by extracting and concentrating tea leaf ingredients. The tea concentrate may be a liquid tea concentrate solution, a tea concentrate powder prepared by drying the tea concentrate solution, or a mixture thereof.

The packaged green tea beverage described herein can be produced by conventionally filling a beverage container with the green tea beverage. As the beverage container, any containers used in this technical field can be used without limitation. For example, plastic bottles, cartons, cans, or glass bottles may be used.

The term ppm described herein refers to mass ppm. For example, when 100 ml of water contains 2 mg of caffeine, the caffeine concentration is referred to as 20 ppm.

The low-caffeine green tea beverage described herein refers to a green tea beverage containing caffeine in a concentration lower than caffeine concentrations of general green teas, or containing no caffeine at all. The caffeine concentration in the packaged green tea beverage of the present invention may be, for example, 50 ppm or less, preferably 30 ppm or less, and more preferably 20 ppm or less. The caffeine concentration can be measured by normally used methods such as high-performance liquid chromatography (HPLC) . For example, a green tea beverage which is a measuring object is diluted two-fold with purified water and filtered through a 0.45-pm syringe filter. Then, the resultant is used as a measurement sample, and can be measured under the following conditions.

Apparatus: a set of Waters UPLC system (detector: PDA gradient method)

Mobile phases : 0.5% formic acid (eluent A), 0.5% formic acid/methanol (eluent B)

Column: Waters Acquity UPLC BEH C18

1.7 pm, 2.1 x 100 mm

Flow rate: 0.3 ml/minute

Gradient: Flow of A/B at the ratio of 90/10 is kept for 2 minutes and then flow at the ratio of 65/35 is kept for 11 minutes.

The low-caffeine green tea beverage can be produced by mixing a tea leaf powder and/or a tea concentrate with water and preparing a solution containing each ingredient in predetermined concentrations. The method for producing the low-caffeine green tea beverage does not necessarily have to include a step of brewing a green tea beverage directly from a raw-material tea leaf. The step of brewing a green tea beverage directly from a raw-material tea leaf refers to adding water to a raw-material tea leaf, extracting ingredients of the raw-material tea leaf, and separating a green tea beverage as a readily drinkable beverage from the residual raw-material tea leaf, where the extraction has been finished. This step does not comprise a step of producing a green tea beverage by using the tea leaf powder and/or the tea concentrate, where the beverage is prepared only by mixing it with water and the above extraction or separation step is not comprised; and does not comprise a step of preparing the tea concentrate which is never served for drinking as it is.

The tea leaf powder and/or the tea concentrate may be those subjected to a caffeine reduction treatment. As a method for the caffeine reduction treatment described herein, any methods used in this technical field can be used without limitation, as long as the method can reduce or remove caffeine from a green tea beverage. For example, the following methods may be used: an extraction-removal method using supercritical carbon dioxide; an adsorption-removal method using activated carbon, activated clay, acid clay, and the like; a method using a synthetic adsorbent; a method using a molecular sieve such as zeolite; or a deposition-separation method using an enzyme such as a tannase.

The non-polymeric catechin described herein is a generic term of non-epi-form catechins (such as catechin, gallocatechin, catechin gallate, and gallocatechin gallate) and epi-form catechins (such as epicatechin, epigallocatechin, epicatechin gallate, and epigallocatechin gallate). The concentration of the non-polymeric catechin can be defined based on a total amount of the aforementioned eight types of compounds. The packaged green tea beverage of the present invention can contain the non-polymeric catechin without particular limitation, provided that its concentration is within the range where favorable astringency and bitterness are imparted. The concentration of the non-polymeric catechin may be, for example, 3000 ppm or less, 1000 ppm or less, or 500 ppm or less, and preferably 300 ppm or less. In the packaged green tea beverage of the present invention, even if the concentration of the non-polymeric catechin is low, addition of dimethyl sulfide described later makes it possible to provide a packaged green tea beverage excellent in astringency, bitterness, and the like. In this case, the concentration of the non-polymeric catechin may be, for example, 100 ppm or more, preferably 130 ppm or more, and more preferably 150 ppm or more. The non-polymeric catechin concentration can be measured by normally used methods such as HPLC, and can be measured, for example, under the same conditions as those employed in the above-described measurement for caffeine.

The tannin described herein is a generic term of complex aromatic compounds having many phenolic hydroxyl groups, which are widely distributed in the plant kingdom, and can include non-polymeric catechins and polymeric catechins. The packaged green tea beverage of the present invention can contain the tannin without particular limitation, provided that its concentration is within the range where favorable astringency and bitterness are imparted. The concentration of the tannin may be, for example, 3500 ppm or less, 1200 ppm or less, or 600 ppm or less, and preferably 350 ppm or less. In the packaged green tea beverage of the present invention, even if the concentration of the tannin is low, addition of dimethyl sulfide described later makes it possible to provide a packaged green tea beverage excellent in astringency, bitterness, and the like. In this case, the concentration of the tannin may be, for example,

250 ppm or more, preferably 280 ppm or more. The concentration of the tannin can be measured by normally used methods such as the method using ferrous tartrate, and can be measured, for example, according to the colorimetric method using ferrous tartrate, which is described in Shokuhin Bunseki Hou (food analysis method) (Tokuj i Watanabe, KourinCo. Ltd. (1982), pp . 813-816, section of tea catechin quantification method).

The dimethyl sulfide described herein can improve the palatability, good flavor, good umami and sweetness, good astringency and bitterness, and strength of taste of a low-caffeine green tea beverage, in which a taste is weak and a preference is decreased. The dimethyl sulfide may be added to the low-caffeine green tea beverage as the sole compound or as a flavor containing the compound, preferably as a green tea flavor containing dimethyl sulfide. Concentration of the dimethyl sulfide in the packaged green tea beverage of the present invention can be set without particular limitation, provided that its concentration is within the range where the above-described effects are effectively exerted and the flavor of dimethyl sulfide itself does not become too strong. For example, the concentration of the dimethyl sulfide may be 0.05 to 1.00 ppm, preferably 0.10 to 0.70 ppm, and more preferably 0.15 to 0.50 ppm. The concentration of the dimethyl sulfide can be measured by normally used methods such as GC/MS analysis employing a solid phase microextraction (SPME) method (SPME-GC/MS), and can be measured, for example, by SPME-GC/MS under the following conditions.

Fiber for the SPME method: Divinylbenzene/carboxen/polydimethylsiloxane manufactured by Supelco

Extraction: 50°C, 20 minutes

GC/MS: Agilent 5973N

Column: DB-WAX (0.25 mm I.D. χ 30 m χ 0.25 gm) Carrier gas flow rate: 1.0 ml/minute

Oven: 30°C (5 minutes) 8 °C/minute 240°C (5 minutes) Inlet temperature: 240°C

The packaged green tea beverage of the present invention may contain an optional additive in addition to the above-described ingredients. As the optional additive, any additives used in this technical field can be used without limitation. For example, vitamin C or sodium bicarbonate may be used.

Examples

A tea concentrate solution, in which a caffeine content had been reduced by a tannase treatment, and a tea concentrate powder, in which a caffeine content had been reduced by an activated-carbon treatment, were mixed with water such that the concentration of the tea concentrate solution was 5.0 g/L, and that the concentration of the tea concentrate powder was 0.5 g/L. The concentration of the caffeine and the concentration of the non-polymeric catechin in the resultant solution were measured by HPLC, and the concentration of the tannin was measured by the method using ferrous tartrate. Table 1 shows the result of the measurement of each concentration.

(Table 1)

Ingredient	Concentration
Caffeine	10 ppm
Non-polymeric catechin	170 ppm
Tannin	300 ppm

Vitamin C and sodium bicarbonate were added to the above solution, and a green tea flavor containing dimethyl sulfide 5 was not added (Group 1), was added (Group 2), or was added in an amount three times as large as that in Group 2 (Group 3), to prepare green tea beverages. The green tea beverages of Groups 1 to 3 were subjected to ultra-high temperature sterilization (UHT sterilization), and aseptic filling (ASP 10 filling) was performed to prepare packaged green tea beverages .

The concentrations of the dimethyl sulfide in the packaged green tea beverages were measured by SPME-GC/MS. Organoleptic evaluation of the packaged green tea beverages were performed on a 5-point scale (N=9), on the basis of Group 1 (3 points) .

Table 2 shows the result of the measurement of the concentration of the dimethyl sulfide and the result of the organoleptic test.

(Table 2)

Group 1 Group 2 Group 3

Concentration of the dimethyl ppm 0.16 ppm 0.46 ppm sulfide

Palatability	3	3.3	3.2
Good flavor	3	3.4	3.7
Good umami and sweetness	3	3.6	3.7
Good astringency and bitterness	3	3.7	3.3
Strength (degree) of taste	3	3.2	3.4

The packaged green tea beverage of Group 1 prepared from the tea concentrate solution and the tea concentrate powder having low caffeine contents did not contain dimethyl sulfide and had weak taste and flavor. When the flavor containing dimethyl sulfide were added thereto, all the items evaluated in the organoleptic test, that is, the palatability, good flavor, good umami and sweetness, good astringency and bitterness, and strength of taste, were improved (Groups 2 and 3).

In view of the above, it was revealed that addition of dimethyl sulfide can improve the reduced taste and flavor of a packaged green tea beverage, which are caused by reducing the caffeine content, and enhance the preference for the beverage.

Claims

Claims

1. A packaged green tea beverage comprising:

50 ppm or less of caffeine;

100 ppm or more of a non-polymeric catechin; and

0.05 ppm or more and 1.00 ppm or less of dimethyl sulfide .
2. The packaged green tea beverage according to claim 1, comprising a tea leaf powder subjected to a caffeine reduction treatment.
3. The packaged green tea beverage according to claim 1 or

2, comprising a tea concentrate subjected to a caffeine reduction treatment.
4. The packaged green tea beverage according to any one of claims 1 to 3, which is produced by a method not comprising a step of brewing a green tea beverage directly from a tea leaf.
5. A method for producing a packaged green tea beverage, comprising a step of preparing a solution containing 50 ppm or less of caffeine, 100 ppm or more of a non-polymeric catechin, and 0.05 or more and 1.00 ppm or less of dimethyl sulfide, wherein the method does not comprise a step of brewing a green tea beverage directly from a tea leaf.
6. The method for producing a packaged green tea beverage according to claim 5, further comprising a step of adding a tea leaf powder and/or a tea concentrate which have been subjected to a caffeine reduction treatment.