JPS60248132A - Green tea drink contained in closed container and production thereof - Google Patents

Abstract

PURPOSE:To prevent the occurrence of browning or deterioration in flavor in preservation, particularly hot venders, by reducing the volume of oxygen based on unit volume of a container to a specific value or below. CONSTITUTION:A green tea drink obtained by adding green tea leaves to heated ion exchange water, extracting green tea decoction, filtering the resultant extract, filling the extract in a container, and closing up the container. In at least one step of the above-mentioned steps, an inert gas is blown into the extract or the space above the extract. The volume of the inert gas to be blown is set to give <=0.004ml/cm<3>, preferably <=0.002ml/cm<3>, based on unit volume of the container, and the extract is heat-treated after blowing the inert gas thereinto.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a green tea beverage packaged in a closed container such as a can and a method for producing the same.

[Prior art and its problems]

In recent years, with the diversification of consumer tastes, various canned beverages have been sold mainly through vending machines.

These include coffee, cocoa, black tea, oolong tea, etc., but canned green tea drinks, which are consumed on a daily basis, have not yet appeared on the market. This is because green tea has a unique flavor and its bright green color appeals to consumers' eyes and stimulates their appetite. Although it is tempting, when canning green tea, the manufacturing process from extraction of tea liquid from tea confectionery to filling and sealing into cans to heat sterilization, and storage in vending machines and other cases after manufacturing. During this period, browning occurs due to oxidation, and the unique flavor of green tea is also lost.

In particular, it is thought that canned green tea drinks are often sold after being kept warm in a hot vendor;
It is necessary to perform the above heat treatment (preferably heat treatment at 115°C for 5 minutes or more), and if the heat sterilization conditions become severe, the degree of browning A3 and flavor deterioration of the green tea beverage may become even greater. understood.

Japanese Patent Publication No. 48-19947 discloses that when processing natural fruit juices such as oranges and lemons, inert gas is blown into the fruit juice stock solution to forcibly discharge dissolved oxygen in the fruit juice, and the inert gas is saturated and dissolved. In addition, a method for processing fruit juice is disclosed in which the fruit juice is subjected to heat sterilization, cooling, etc., and then led to an ejector, where an inert gas is captured and added, and then supplied to a container filling process. . However, this method relates to the treatment of natural fruit juice and cannot be directly applied to green tea, which requires a different treatment method.

[Purpose of the invention]

An object of the present invention is to provide a green tea beverage in a closed container that does not cause browning or flavor deterioration during storage, particularly during storage in a hot vendor, and a method for producing the same.

[Structure of the invention]

The green tea beverage in a sealed container of the present invention which achieves the above object is characterized in that the oxygen per unit volume of the container [i] is 0.002 d/cd or less (preferably 0.001 s+e/cat or less). By suppressing the amount of oxygen in the container in this way, browning and flavor deterioration will not occur even during long-term storage, especially long-term storage in hot bender.

In order to achieve the above objective, it is necessary to specify the amount of dissolved oxygen in the tea liquid filled in the container to be below a certain amount, and also to specify the amount of oxygen in the head space of the container to be below a certain amount.

When measuring the amount of oxygen in the can, the oxygen image in the headspace and the amount of dissolved oxygen in the liquid have a constant ratio according to the law of partial pressure. Therefore, by measuring the amount of oxygen in the headspace, the total amount of oxygen in the can can be estimated.

Expressing this relationship concretely, the amount of oxygen per unit volume of the head space of the beverage container according to the present invention is approximately O,
OO1++e/m or less.

Furthermore, the method for producing a green tea beverage in a sealed container according to the present invention which achieves the above object includes a step of heating ion-exchanged water to a tea liquid extraction temperature, and a step of adding tea leaves to the heated ion-exchanged water to extract tea liquid. , a step of heating the tea liquid extract by 3P, and a step of filling a container with the filtered extract and sealing it.In at least one of these steps, an inert gas is added to the extract or By blowing into the side bulge, the amount of oxygen per unit sound (i) of the container is reduced to 0.004 td/
cIIi or more 1ζ (preferably GEL O, OO2rtd
l/c#i or less), and is then heat-treated.

As is clear from the above, one feature of the method of the present invention is to produce and preserve green tea beverages in sealed containers by expelling oxygen in the container using an inert gas and suppressing the amount of oxygen in the container to a certain amount or less. The point is that it has solved the problems associated with.

Incidentally, it goes without saying that a can is most suitable as a container for filling the green tea beverage of the present invention, but the container is not limited to this, and plastic containers such as a standing pouch can also be used.

〔Example〕

Preferred embodiments of the invention will now be described with reference to the accompanying drawings.

Example 1 24 kg'□ of ion-exchanged water was once boiled and then allowed to cool to 80°C, and 0.2 kg of deep-steamed green tea from Company A was added to this ion-exchanged water in 50ρ tank 1 shown in Fig. 1. ℃3
Extracted for minutes. Prior to extraction, nitrogen gas from nitrogen gas FA7 was blown into the ion exchange water through pipe 2. After extraction, remove the base grains using a coarse wire mesh colander, and add 60% of the tea liquid extract.
Metsu stainless steel sieve 3 to 5? Passed? Transfer the filtered extract to a 200g can 6 using Cybon 4 at 190~195
g filled. At that time, pipe 5 is inserted into the head space of can 6.
Nitrogen gas was blown through the tube. Next, manually close the can lid 6.
A was fitted onto the can body gb and seamed with a seamer 8. Immediately before fitting the can lid 6a onto the can body 6b, nitrogen gas was blown into the head space through the pipe 9. After sweating, retort sterilize at 115℃ for 10 minutes.

Example 2 50 kg of ion-exchanged water was heated, and as shown in Fig. 2,
50.11 Inject into the tank 10 through the inlet 10a,
Add 625g of Bne1 Tsurudori Sencha to Tank'IO,
Extraction was performed at 80°C for 2 minutes. Nitrogen gas is removed prior to extraction.
Nitrogen is injected into the ion-exchanged water through the f-tube 11, and during extraction, to prevent the extract from becoming cloudy due to excessive stirring, the nitrogen injection into the extract is stopped and the tank space above the extract is replaced. Nitrogen gas was blown into the tank 12 through the nozzle 13. After extraction, pass the extract through a 60-mesh stainless steel sieve.
4 for a first filtration, and then a 200 mesh nylon cloth 1b for a second filtration.

The extracted liquid was heated to 40°C at 85°C in an O-filled tank 16.
It was heated to and kept warm. During this time, nitrogen gas was blown into the extract via the vibrator 17. Note that the filling tank 16 is installed and inserted into a heat insulating tank 18 filled with dry water for heat preservation. Next, this filling tank 16 is connected to the gas line 30.
2003 can 21 was filled with 190 to 195 g of the extract by opening and closing the supply cock 20 in the supply pipe 19.

In this step as well, nitrogen gas was blown into the extract in the filling tank 16 and the head space of the can through the pipe 22 and 23, respectively. Next, the can filled with the extract liquid is transferred to a seamer 24 equipped with a known undercover gashing device (not shown), and before fitting the can lid, nitrogen is supplied through the slit of the cap feed turret of the undercover gashing device. Gas was injected into the space between the can lid and the can body. After the can was rolled up, it was cooled and retort sterilized at 110°C for 15 minutes. The nitrogen blowing rate was 101 N/min in the extraction process and the filling process, and 96 N/min in the undercover gassing process.

Example 3 Heat 40 ICg of ion-exchanged water and make 50 ICg of company C deep steamed green tea.
0 g was extracted, filtered, and filled in the same manner as in Example 2, and nitrogen gas was blown in each step in the same manner as in Example 2. Next, the can filled with the extract liquid is transferred to a seamer 24 (Fig. 2) equipped with a known steam injection mechanism (not shown), and steam is injected into the color headspace from a steam nozzle at 0.1 to 9/ai. The can lid was immediately fitted onto the can body and sealed. After cooling, retort sterilization was performed at 110° C. for 15 minutes.

Example 4 Extraction, 5 filtration, and filling were carried out using the same method as in Example 3, and nitrogen gas was blown into each step in the same manner as in Example 3. Next, using the same seamer as in Example 3, 2 kg/ci of nitrogen was injected into the head space of the can from the steam nozzle, and the can was sealed and retorted in the same manner as in Example 3.

Example 5 A canned green tea beverage was produced in the same manner as in Example 3, except that nitrogen gas was not blown in each of the extraction, filtration, and filling steps.

Example 6 A canned green tea beverage was produced in the same manner as in Example 4, except that extraction, 5 filtration, and filling table 1 did not blow nitrogen gas into the culm.

〔Effect of the invention〕

According to the method of the present invention, the head space oxygen amount in the can and the dissolved oxygen m in the liquid are as shown in Table 1 below, and the total oxygen amount in the can can be suppressed to 0.002 m/cd or less per unit volume. Ta.

Table 1 Oxygen port 1 (d) Head space Dissolved oxygen Total amount Example 1 0.20 0.19 0.39 Example 2 0
．． 15 0.17 0.32 Example 3 0.18 0.
20 0.38 Example 4 0.20. 0.18 0.
38 Example 5 0.14 0.16 0.30 Example 6
0.17 0.19 0.36 Normal method 0.65 0
．． ．． 74. 1.39 The green tea beverage of the present invention has a color difference ΔF before and after retort according to the present invention, as shown in the sample bust in Table 2 below, by suppressing the oxygen in the can to a predetermined level or less during sealing as described above. It is much smaller than those produced by conventional methods, maintains a bright green color even after being poured into the rettle 1, and has a good flavor. On the other hand, it was observed that those produced by the conventional method were significantly browned after torturing, had a flavor similar to [111 tea], and had an increased astringency.

Note 1. The same method as in Example 1 was used, except that each culm was not blown with nitrogen and the seaming was done in the usual manner in the presence of air.

Note 21 Colors are measured transmission based on color difference a1.

Furthermore, canned green tea beverages were heat sterilized under various sterilization conditions, and the occurrence of variables at 30°C and 55°C was examined, and the results shown in Table 3 below were obtained.

Table 3 As a result, to store green tea beverages at room temperature, heat sterilization at 100°C for about 4 minutes is required, but to store them in a Hora l-bender, heat sterilization at 115°C for 1'5 minutes or more is required. It was found that the range of suitable heat sterilization conditions is 100°C to 125°C for 1 minute to 15 minutes.

As shown in Table 4 below, the green tea beverage according to the present invention, which was heat sterilized after being rolled up under the above conditions, hardly changes its color even after being stored at 55°C for 4 weeks. It was found that it could withstand storage.

Table 4

[Brief explanation of drawings]

FIG. 1 is a diagram showing an apparatus for implementing one embodiment of the method for manufacturing a green tea beverage in a sealed container of the present invention, and FIG. 2 is a diagram showing an apparatus for implementing another embodiment of the present invention. It is. .

Claims (1)

[Claims] 1. Oxygen amount per unit volume is 0.002 sd! /ci
A green tea beverage in a sealed container characterized by the following: 2. After filling the container and sealing it, heat at 100℃ to 125℃ for 1 minute to 1 minute.
The green tea beverage in a sealed container according to claim 1, which is heat sterilized for 5 minutes. 3. Heating the ion-exchanged water to the tea liquid extraction temperature;
The process includes a step of adding tea confectionery to heated ion-exchanged water to extract tea liquid, a step of filtering the tea liquid extract, and a step of filling a container with the extracted liquid after three filtration and sealing it. In at least one of the steps, by blowing an inert gas into the extract liquid or into the space above it, the amount of ribs per unit volume of the container before heat treatment is reduced to n-(1n4-/-
A method for producing a green tea beverage in a sealed container, characterized by the following: 4. The method for producing a green tea beverage in a closed container according to claim 3, wherein the container is a can. 5. The airtight container according to claim 4, characterized in that the head space of the can is depressurized by injecting an inert gas into the joint between the can body and the transmission during a3 tightening of the can. Method for producing green tea beverage. 6. Green tea in an airtight container according to claim 4, wherein the head space of the can is depressurized by injecting steam into the joint between the can body and the can lid when the can is sealed. Beverage manufacturing method.