JP6180378B2 - Method for producing tea beverage - Google Patents

Description

  The present invention relates to a method for producing a tea beverage. More particularly, the present invention relates to a processing method and a sterilizing method for tea leaf leachate and a method for producing a tea beverage by these methods.

  At present, a heat sterilization method is usually used as a sterilization method for processing tea beverages, and conventional tea beverage production methods usually include a high temperature sterilization process.

  On the other hand, as a method for sterilizing gardenia rush without using high temperature, Patent Document 1 discloses a method of extracting gardenia rush by ultra-high pressure extraction and ultra-high pressure sterilization to obtain a beverage. According to Patent Document 1, ultra-high pressure extraction is performed by crushing into 1 to 3 mm fine granules, immersed in drinking water at a weight ratio of 1 to 5: 100 for 15 minutes, and held at a pressure of 100 to 250 MPa for 5 to 20 minutes. It has been done. Furthermore, the extract obtained by filtration is sealed in an aluminum foil and a plastic composite material, and sterilized by being held at a pressure of 250 to 450 MPa through water for 5 to 15 minutes.

Chinese Patent Application No. 102228110

  The high-temperature sterilization process included in the conventional tea beverage manufacturing process destroys the sweetness component of tea and adversely affects its flavor. Therefore, a sterilization method that does not use high temperature is desired.

  Then, this invention aims at providing the manufacturing method of the tea drink which can hold | maintain favorable flavor, even when it preserve | saves for a long time, without using high temperature.

  The present inventors have intensively studied to solve the above problems. As a result, it has been found that the above problems can be solved by treating the tea infusion liquid at a high pressure, and the present invention has been completed.

  That is, according to one aspect of the present invention, the method includes: a) a step of sealing the tea infusion in a soft container; and b) a step of pressurizing the sealed container at a pressure of 100 to 600 MPa for 0.1 to 10 minutes. A method for producing a tea beverage is provided.

  The obtained product has the advantage that it can be stored refrigerated or at room temperature, and the flavor unique to tea leaves can be well preserved.

  The method for producing a tea beverage according to an embodiment of the present invention includes: a) a step of sealing (sealing) a tea infusion in a soft container; and b) the sealed container at a pressure of 100 to 600 MPa for 0.1 to 10 minutes. Applying a pressure treatment.

  The present invention provides a method for processing a tea leaf leachate and a method for sterilization. The obtained tea beverage can be stored for a long time at refrigeration or at room temperature, and can retain a good flavor even if stored for a long time.

  Moreover, the sterilization method which concerns on one Embodiment of this invention is pressurizing at a pressure of 100-600 MPa for 1-10 minutes.

  A conventional method for producing tea leaves includes the steps of fresh leaf picking, sun-dried wilting, indoor wilting, rotary fermentation, roasting in a pot, standing, twisting, thawing, and drying. In other methods, storage by freezing may be performed without drying.

  In one embodiment of the present invention, water is added to undried semi-finished tea leaves (moisture content 30-50% by weight) and dried product tea leaves in a conventional manufacturing process to obtain a tea infusion, preferably at room temperature. Then, it is sterilized by high pressure (> 100 MPa) treatment. The product obtained by such a sterilization method can be stored at refrigeration or at room temperature, and has the merit of preserving the flavor unique to tea leaves.

  In the present specification, undried semi-finished tea leaves are those having a water content of 30 to 50% by weight.

  In the present specification, the tea leaf is not particularly limited as long as it is a commercially available tea leaf. Longjing tea, iron kannon tea, baling tea, oolong tea, black tea, Earl Gray tea, or Yuka tea can be used.

  As described above, the tea infusion is obtained by immersing dried tea leaves or undried semi-finished tea leaves in water as an extraction solvent at a predetermined weight ratio and extracting the tea leaves. If water is drinking water, it will not be restrict | limited in particular.

  The ratio of tea leaves to water may be set according to the type of tea leaves and the taste required by consumers, and is not particularly limited, but for example, tea exudates are dried tea leaves or undried semi-finished products It is obtained by immersing tea leaves in water at a weight ratio (tea leaves: water) of 1: 5 to 1: 200. More preferably, the tea leaf leachate is obtained by immersing dried tea leaves or undried semi-finished tea leaves in water at a weight ratio (tea leaves: water) of 1: 5 to 1:20.

  In one embodiment, the temperature of water in which dried tea leaves or undried semi-finished tea leaves are immersed, that is, the temperature of extraction water is preferably 0 ° C. to 50 ° C. from the viewpoint of reducing energy. The extraction water is preferably not heated from the viewpoint of reducing energy. However, since the immersion time can be shortened, a temperature of room temperature (25 to 35 ° C., for example, 25 ° C.) or higher may be used, and a temperature of room temperature or higher and 50 ° C. or lower is also preferable. In this case, it is necessary to remove the tea leaves from the tea beverage.

  The immersion time of the tea leaves, that is, the extraction time may be set according to the type of tea leaves and the taste required by the consumer, and is not particularly limited, but an example is 0.5 to 24 hours. It is preferable. Further, the pressure is not particularly limited in the tea leaf dipping step, and is, for example, normal pressure.

  Preferably, the tea infusion is obtained by immersing the tea leaves in water and then removing the tea leaves by solid-liquid separation. The method of solid-liquid separation is not particularly limited, and examples thereof include a method of filtering by a conventional method.

  In addition, when not performing the said solid-liquid separation process, tea infusion liquid contains tea leaves. Such a form is also preferred. That is, in one preferred embodiment, the tea infusion contains tea leaves. In such a case, it is not necessary to remove the tea leaves from the flexible container, so that the immersion time is shortened, which means an increase in production speed in a relatively small factory.

  Next, the tea infusion obtained in this way is sealed (enclosed) in a soft container (step a).

  In a preferred embodiment of the invention, the flexible container is selected from the group consisting of a plastic composite film, a plastic bag, and a plastic bottle. This is because it can be easily obtained in the market.

Thereafter, the sealed container is pressurized at a pressure of 100 to 600 MPa for 0.1 to 10 minutes (step b). By this treatment, a tea beverage that is sterilized while retaining the sweetening component of tea and can be stored for a long time is obtained. When the pressure exceeds 600 MPa, it is not preferable from the viewpoint of the cost of energy and the cost of pressure equipment. Pressure is not practical time becomes too long required sterilization process is less than 100 M Pa. If the pressure treatment time exceeds 10 minutes, the energy cost increases when the pressure is maintained at the same pressure, which is not preferable. When the pressure treatment time is less than 0.1 minutes, the sterilizing effect of bacteria is insufficient when the pressure value is 600 MPa or less. More preferably, in step b), the pressure treatment is performed at 300 to 600 MPa for 0.1 to 5 minutes.

  Moreover, it is preferable to perform a pressurizing process in the temperature of 0-50 degreeC in process b).

  Hereinafter, although the effect by this invention is demonstrated using an Example and a comparative example, the technical scope of this invention is not limited to these Examples. In addition, in this specification, normal temperature is the temperature in the state which does not perform cooling and heating, Comprising: Room temperature (25-35 degreeC) is meant.

The following examples employ the following materials and methods:
1.1 Experimental Materials 1.1.1 Dried tea leaves (type: oolong tea) or undried semi-finished tea leaves (type: oolong tea; moisture content about 40% by weight); and 1.1.2 cold drinking water.

1.2 Experimental Method 1.2.1 High Pressure Equipment Using a high pressure equipment (QFP2L-700, manufactured by Avure Technologies, Sweden), pressure is applied to the medium water. The package is a plastic bag made of polyethylene terephthalate (PET). That is, the sealed plastic bag in which the tea infusion liquid is sealed is pressurized.

1.2.2 Viable count 1 ml of well mixed preparation was taken and diluted to different proportions. 1 ml of the diluted solution was transferred to an aerobic plate count plate (aerobic plate count, 3M Petrifilm plate, St. Paul, Minnesota, USA) and cultured at 35 ° C. for 48 hours, and then red colonies were counted. Two measurements were taken for each dilution.

1.2.3 Number of mold yeast 1 ml of a well mixed sample was taken and diluted in different proportions. 1 ml of the diluted solution was transferred to a yeast and mold measurement plate (yeast and mold count plate, 3M Petrifilm plate, St. Paul, Minnesota, USA) and cultured at 25 ° C. for 3 to 5 days, and colonies were counted. Two measurements were taken for each dilution.

[Example 1: Effectiveness of high-pressure sterilization for tea leaf-containing leachate]
After taking 1 g of undried semi-finished tea leaves and adding 10 g, 20 g or 200 g of water (room temperature) under normal pressure, further, Listeria innocua or L. innocua or Aspergillus niger; A. niger ) Added bacterial solution. Some tests did not add bacterial solution. The tea infusion thus obtained was sealed in a plastic bag as a flexible container, and a pressure of 100 MPa to 600 MPa was applied at room temperature and held for 0.1 to 10 minutes. The results of measuring the number of viable cells and the number of mold yeasts are represented by logarithms as shown in Table 1. The pressure treatment at 100 to 600 MPa for 0.1 to 5 minutes was able to reduce the logarithmic value of the number of bacteria and mold yeast from 2.5 to 5.8.

[Example 2: Effectiveness of high-pressure sterilization for tea leaves exudate]
10 g or 30 g of water (room temperature) was added to 1 g of undried semi-finished tea leaves, and after 1 hour, the tea leaves were removed by filtration. innocua and A.I. Niger bacteria solution was added (normal pressure), sealed in a plastic bag, sealed, and pressurized at 300 MPa at room temperature for 3 or 5 minutes. Table 2 shows the results of analyzing the viable cell count and the mold yeast cell count. These show that the present invention effectively killed bacteria, mold and yeast.

[Example 3: Long-term preservation of tea leaf exudate sterilized under high pressure]
5 to 20 g of water (room temperature) is added to 1 g of dried tea leaves or undried semi-finished tea leaves under normal pressure, and 0.1 ml of Bacillus subtilis spores or L. innocua solution was inoculated. It was sealed in a plastic bag and then pressurized at 600 MPa for 3 minutes or 10 minutes at room temperature. The obtained product could be stored at 4-10 ° C. refrigeration or at room temperature for 30 days, and could be stored for up to 70 days. As shown in Table 3, the results were refrigerated or stored at room temperature for 30 days.

[Example 4: Evaluation of flavor of tea infusion after autoclaving]
7.5 parts by weight of water was added to 1 part by weight of undried semi-finished tea leaves (room temperature). Further, 20 parts by weight of water was separately added to 1 part by weight of undried semi-finished tea leaves (room temperature). These were each sealed in a plastic bag (normal pressure), and the plastic bag was pressurized at 600 MPa and room temperature (25 to 35 ° C.) for 3 minutes. After storage at 4-10 ° C. for 100 days, the leachate was taken out and diluted with a suitable amount of water to a Brix degree of 0.6-0.7. The diluted leachate had a strong aroma and sweetness in the back, astringency was weak, and the brown color was light. In contrast, when the leachate that was pressure-treated in the same way as above except that the temperature of the water added to the tea leaves was 85 ° C. was diluted with a suitable amount of water to a Brix degree of 0.7, the astringency and brown were fairly strong and dark colors Met.

  10 parts by weight of water (room temperature) was added to 1 part by weight of the dried tea leaves, sealed in a plastic bag (normal pressure), and the plastic bag was pressurized at 450 MPa at room temperature (25-35 ° C.) for 1 minute. After storage at 4-10 ° C. for 32 days, the leachate was removed and diluted with an appropriate amount of water to a Brix degree of 0.6-0.7. The diluted leachate had a mild astringency, had a fragrance and a sweetness on the back, and was rather light brown. Compared with that, except that the temperature of the water added to the tea leaves was 95 ° C, the exudate that had been pressure-treated in the same manner as above was diluted with an appropriate amount of water to a Brix degree of 0.7. Met.

Claims (9)

a) sealing a tea infusion obtained by immersing dried tea leaves or undried semi-finished tea leaves in water in a weight ratio (tea leaves: water) of 1: 5 to 1:30 in a soft container; and b) Pressurizing the sealed container at a temperature of 0 to 35 ° C. for 0.1 to 10 minutes at a pressure of 100 to 600 MPa;
A method for producing a tea beverage, comprising:   The manufacturing method according to claim 1, wherein the flexible container is selected from the group consisting of a plastic composite film, a plastic bag, and a plastic bottle.   The manufacturing method of Claim 1 or 2 which performs a pressurization process in the said process b) by the pressure of 300-600 MPa.   The tea infusion is obtained by immersing dried tea leaves or undried semi-finished tea leaves in water at a weight ratio (tea leaves: water) of 1: 5 to 1:20. 2. The production method according to item 1.   The said tea infusion liquid is a manufacturing method of any one of Claims 1-4 containing a tea leaf. The said tea leaching liquid is a manufacturing method of any one of Claims 1-4 obtained by removing the said tea leaf by solid-liquid separation, after immersing the said tea leaf in water.   The temperature of the said water is a manufacturing method of any one of Claims 1-6 which are 0 degreeC-50 degreeC. The manufacturing method according to any one of claims 1 to 4, 6, and 7, wherein the tea leaves are immersed for 0.5 to 24 hours. a) A tea infusion containing tea leaves obtained by immersing dried tea leaves or undried semi-finished tea leaves in water at a weight ratio (tea leaves: water) of 1: 5 to 1:30 is sealed in a soft container. And b) pressure-treating the sealed container at a temperature of 0 to 35 ° C. for 0.1 to 10 minutes at a pressure of 100 to 600 MPa;
A method for producing a tea beverage, comprising: