Process for extracting tea essence powder from tea water extract

Abstract

The invention relates to the technical field of tea flavor powder extraction, and discloses a process for extracting tea flavor powder from a tea water extract, which comprises the following steps: S1, selecting raw materials; s2, raw material treatment; s3, cold extraction and concentration; s4, performing freeze drying; and S5, packaging. Raw tea which is high in quality and free of impurities is selected as a raw material during raw material selection, the selected tea raw material is screened after selection, so that the uniformity of the raw material is ensured, freeze drying comprises the steps of pre-freezing, vacuum freeze drying and re-drying, the tea can be placed in a low-temperature environment through pre-freezing, and the tea can be placed in a low-temperature environment through vacuum freeze drying. According to the invention, the tea leaves are frozen into ice crystals, so that the moisture contained in the tea leaves can be quickly frozen into ice crystals, the moisture can be directly sublimated from a solid state to a gas state in a subsequent vacuum freezing stage, the main performance of the tea leaves can be protected, the tea leaves can be prevented from oxidative deterioration through vacuum freeze drying, and finally the moisture can be further removed through re-drying, so that the quality and stability of the product are improved; therefore, the shelf life and the storability of the product are prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of tea essence powder extraction, in particular to a process for extracting tea essence powder from tea water extract. Background Art

[0002] Tea leaves, commonly known as tea, generally include the leaves and buds of the tea tree. The ingredients of tea include catechins, cholestenone, caffeine, inositol, folic acid, and pantothenic acid, which are good for health. Tea beverages made from tea leaves are one of the three major beverages in the world.

[0003] Tea water extract refers to the soluble substances extracted from tea under specified conditions. These substances include polyphenols, soluble sugars, water-soluble pectin, water-soluble vitamins, free amino acids, caffeine, water-soluble proteins, inorganic salts, etc. These ingredients give tea its unique aroma, taste and health functions.

[0004] Tea extract powder extracted from tea water extract can retain many beneficial ingredients in tea, making it easy to add to various foods and drinks.

[0005] However, at present, when extracting and selecting tea leaves from water extract, the tea leaves are generally directly selected without selecting and screening the tea leaves, resulting in low uniformity of the selected tea leaves, which affects the quality of the subsequent extracted tea essence powder. In addition, when freeze-drying, the tea leaves are directly cooled and dried in a vacuum freeze dryer without pre-freezing, which affects the product quality and reduces its storage performance. Therefore, those skilled in the art provide a process for extracting tea essence powder from tea leaves water extract to solve the problems raised in the above background technology. Summary of the invention

[0006] The object of the present invention is to provide a process for extracting tea essence powder from tea water extract to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] The process for extracting tea essence powder from tea water extract comprises the following steps:

[0009] S1. Raw material selection: Select high-quality, impurity-free raw tea as raw material to ensure the quality of the final product;

[0010] S2, raw material processing: the selected raw materials are cleaned and dried for subsequent processing;

[0011] S3, cold extraction and concentration: cold extraction and concentration of the processed tea leaves to form a concentrated liquid;

[0012] S4, freeze drying: freezing the concentrated liquid to form ice crystals, which are then heated and sublimated into water vapor and discharged, thereby obtaining dry tea essence powder;

[0013] S5. Packaging: Choose packaging materials that meet food safety standards to ensure the tea essence powder’s airtightness, moisture resistance, and light protection, and package it in a clean, dry, and sterile environment.

[0014] As a further embodiment of the present invention: the raw material selection includes raw tea selection and screening and grading,

[0015] When selecting the raw tea, high-quality large-leaf tea or other tea varieties suitable for making tea powder should be selected. The tea leaves should be fresh, free of mold and odor;

[0016] The screening and grading is used to remove tea leaves that do not meet the standards, impurities, etc., to ensure the uniformity of the raw materials.

[0017] The screening process includes the following steps: a. Screening using a screen or a vibrating screen. The aperture size of the screen should be determined according to the size of the tea particles required;

[0018] b. Pour the tea leaves into the screening device and roll the tea leaves on the screen by vibrating or shaking. The smaller particles will pass through the screen and fall into the collection container below, while the larger particles will remain on the screen.

[0019] c. Repeat the screening process until the tea leaves are classified into the desired tea leaves.

[0020] As a further solution of the present invention: the raw material processing includes washing and drying,

[0021] The cleaning step involves washing the selected tea leaves with running water to remove dust and pesticide residues on the surface;

[0022] The drying step is to dry the washed tea leaves to a suitable moisture content for easy handling.

[0023] The specific steps of drying are as follows: A. Spread the washed tea leaves evenly on the tea drying rack or in the tea drying room;

[0024] B. Control the temperature and humidity of the drying environment. The temperature of the drying environment should be controlled between 20-30℃, and the humidity should be maintained between 50%-70%. At the same time, direct sunlight and strong wind should be avoided to prevent the tea leaves from changing color or being damaged.

[0025] C. Turn the tea leaves regularly to ensure that they are evenly dried. Be gentle when turning them to avoid damaging the shape and integrity of the tea leaves.

[0026] As a further embodiment of the present invention: the cold extraction and concentration comprises cold extraction and concentration,

[0027] The cold extraction process involves soaking the processed tea leaves in cold water, and gradually dissolving the soluble components in the tea leaves into the water through long-term soaking at low temperature.

[0028] The concentration is mainly carried out by vacuum concentration method to remove water from the soaked tea juice to form a concentrated solution.

[0029] As a further solution of the present invention: the temperature of the cold water soaking is 5-10°C, the cold extraction time is 8-12 hours, and the ratio of tea to water soaking is 1:50 or 1:100.

[0030] As a further solution of the present invention: during the concentration, a filter or a centrifuge is needed to separate the tea soaked in cold water from the tea leaves, and then concentrate the tea juice after obtaining the clear tea juice.

[0031] As a further solution of the present invention: the freeze drying is divided into pre-freezing and vacuum freeze drying, and during the pre-freezing, the concentrated liquid is poured into a tray or a container and quickly frozen under low temperature conditions to form ice crystals;

[0032] During the vacuum freeze drying, the frozen tea concentrate is placed in a vacuum freeze dryer, and the ice crystals are sublimated into water vapor by heating under vacuum and discharged, thereby obtaining dry tea essence powder.

[0033] As a further solution of the present invention: during the pre-freezing, the concentrated liquid is pre-frozen at a low temperature of -25°C to -30°C, the cooling rate is controlled at 2-5°C / min, and the temperature is kept for 1-2 hours after reaching the temperature.

[0034] As a further solution of the present invention: the vacuum cooling and drying is performed at -75°C and a vacuum environment within 5 Pa for up to 48 hours.

[0035] As a further solution of the present invention: the tea powder is dried again after vacuum drying to remove trace moisture in the tea essence powder, and the drying temperature range is 10°C-35°C.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The present invention selects raw tea with good quality and no impurities as raw material, and screens the selected tea raw materials after selection to ensure the uniformity of the raw materials, so as to facilitate the quality of the tea essence powder extracted later. At the same time, the tea raw materials are cleaned and dried after selection to remove dust and impurities on the surface of the tea leaves, so as to ensure the sanitary quality of the tea leaves.

[0038] 2. The present invention uses cold extraction and concentration to put the tea leaves into cold water for long-term low-temperature soaking, so that the soluble components in the tea leaves are gradually dissolved into the water, thereby effectively retaining the fresh aroma and delicate taste of the tea leaves, protecting the active substances in the tea leaves, and fully extracting the nutrients in the tea leaves.

[0039] 3. The freeze-drying of the present invention includes pre-freezing, vacuum freeze-drying and re-drying steps. The pre-freezing can place the tea leaves in a low-temperature environment so that the water contained therein can be quickly frozen into ice crystals, so that the water can be directly sublimated from a solid state to a gaseous state in the subsequent vacuum freezing stage, and the main properties of the tea leaves can be protected. The vacuum freeze-drying can prevent the tea leaves from oxidation and deterioration. Finally, the re-drying can further remove the water, improve the quality and stability of the product, and thus extend the shelf life and storage of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a framework diagram of the process for extracting tea essence powder from tea water extract. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] See also Figure 1 In the embodiment of the present invention, the process of extracting tea essence powder from tea water extract comprises the following steps:

[0043] S1. Raw material selection: Select high-quality, impurity-free raw tea as raw material to ensure the quality of the final product;

[0044] S2, raw material processing: the selected raw materials are cleaned and dried for subsequent processing;

[0045] S3, cold extraction and concentration: cold extraction and concentration of the processed tea leaves to form a concentrated liquid;

[0046] S4, freeze drying: freezing the concentrated liquid to form ice crystals, which are then heated and sublimated into water vapor and discharged, thereby obtaining dry tea essence powder;

[0047] S5. Packaging: Choose packaging materials that meet food safety standards to ensure the tea essence powder’s airtightness, moisture resistance, and light protection, and package it in a clean, dry, and sterile environment.

[0048] In this embodiment, the raw material selection includes raw tea selection and screening and grading.

[0049] When selecting raw tea, choose high-quality large-leaf varieties or other tea varieties suitable for making tea powder. The tea leaves should be fresh, free of mold and odor.

[0050] Screening and grading are used to remove tea fragments and impurities that do not meet the standards to ensure the uniformity of the raw materials.

[0051] The screening process includes the following steps: a. Use a screen or vibrating screen to screen. The size of the screen aperture should be determined according to the size of the tea particles required;

[0052] b. Pour the tea leaves into the screening device and roll the tea leaves on the screen by vibrating or shaking. The smaller particles will pass through the screen and fall into the collection container below, while the larger particles will remain on the screen.

[0053] c. Repeat the screening process until the tea leaves are classified into the desired tea leaves.

[0054] In this embodiment, the raw material processing includes washing and drying.

[0055] Washing: Wash the selected tea leaves with running water to remove dust and pesticide residues on the surface;

[0056] Drying: Dry the washed tea leaves to the appropriate moisture content for easy handling.

[0057] The specific steps of drying are as follows: A. Spread the washed tea leaves evenly on the tea drying rack or in the tea drying room;

[0058] B. Control the temperature and humidity of the drying environment. The temperature of the drying environment should be controlled between 20-30℃, and the humidity should be maintained between 50%-70%. At the same time, direct sunlight and strong wind should be avoided to prevent the tea leaves from changing color or being damaged.

[0059] C. Turn the tea leaves regularly to ensure that they are evenly dried. Be gentle when turning them to avoid damaging the shape and integrity of the tea leaves.

[0060] Specifically, in this embodiment, cold extraction and concentration include cold extraction and concentration.

[0061] Cold extraction is to soak the processed tea leaves in cold water, and the soluble components in the tea leaves are gradually dissolved into the water through long-term soaking at low temperature.

[0062] Concentration is mainly carried out by vacuum concentration method to remove water from the steeped tea juice to form a concentrated liquid.

[0063] When soaked in cold water, the temperature is 5-10°C, the cold brewing time is 8-12 hours, and the ratio of tea to water is 1:50 or 1:100.

[0064] When concentrating, a filter or centrifuge is needed to separate the tea soaked in cold water from the tea leaves, and then concentrate the clear tea juice.

[0065] Specifically, freeze drying in this embodiment is divided into pre-freezing and vacuum freeze drying. During pre-freezing, the concentrated liquid is poured into a tray or container and quickly frozen under low temperature conditions to form ice crystals.

[0066] During vacuum freeze drying, the frozen tea concentrate is placed in a vacuum freeze dryer, and the ice crystals are sublimated into water vapor and discharged by heating under vacuum conditions, thereby obtaining dry tea essence powder.

[0067] During pre-freezing, the concentrated liquid is pre-frozen at a low temperature of -25°C to -30°C, the cooling rate is controlled at 2-5°C / min, and the temperature is kept for 1-2 hours after reaching the temperature.

[0068] During vacuum cooling and drying, freeze drying is performed at -75°C and a vacuum environment of less than 5 Pa for up to 48 hours.

[0069] After vacuum drying, the tea powder is dried again to remove trace moisture in the tea essence powder, and the drying temperature range is 10°C-35°C.

[0070] Performance Testing

[0071] Ten professional perfumers were invited to weigh 0.5 g of each sample of Example 1 and two instant teas available on the market (Comparative Example 1 and Comparative Example 2) after storage for one month. The samples were placed in a 250 mL transparent glass cup and brewed with 150 mL of pure water at 25°C for sensory evaluation. The scoring rules are shown in Table 1 below.

[0072] Table 1

[0073]

[0074] And 10 professional perfumers tasted the tea of ​​this embodiment and the two existing teas and gave scores, as shown in the following Table 2:

[0075] project aroma taste Solubility Soup color Example 95.4 94.7 Dissolved without precipitation Pure color Comparative Example 1 89.4 90.4 Dissolved without precipitation Pure color Comparative Example 2 87.5 89.6 Dissolved without precipitation Pure color

[0076] The storage time of this embodiment and two existing tea essence powders was tested, as shown in Table 3 below:

[0077]

[0078]

[0079] It can be seen from Table 1, Table 2 and Table 3 that the tea essence powder prepared by the present invention can effectively retain the fresh aroma and delicate taste of tea, protect the active substances in the tea, fully extract the nutrients in the tea, and extend the shelf life and storage of the product.

[0080] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0081] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. The process of extracting tea essence powder from tea water extract, It is characterized in that The following steps are involved: S1. Raw material selection: Select high-quality, impurity-free raw tea as raw material to ensure the quality of the final product; S2, raw material processing: the selected raw materials are cleaned and dried for subsequent processing; S3, cold extraction and concentration: cold extraction and concentration of the processed tea leaves to form a concentrated liquid; S4, freeze drying: freezing the concentrated liquid to form ice crystals, which are then heated and sublimated into water vapor and discharged, thereby obtaining dry tea essence powder; S5. Packaging: Choose packaging materials that meet food safety standards to ensure the tea essence powder’s airtightness, moisture resistance, and light protection, and package it in a clean, dry, and sterile environment.

2. The process for extracting tea essence powder from tea water extract according to claim 1, It is characterized in that The raw material selection includes raw tea selection and screening and grading, When selecting the raw tea, high-quality large-leaf tea or other tea varieties suitable for making tea powder should be selected. The tea leaves should be fresh, free of mold and odor; The screening and grading is used to remove tea leaves that do not meet the standards, impurities, etc., to ensure the uniformity of the raw materials. The screening process includes the following steps: a. Use a screen or vibrating screen to screen. The size of the screen aperture should be determined according to the size of the tea particles required; b. Pour the tea leaves into the screening device and roll the tea leaves on the screen by vibrating or shaking. The smaller particles will pass through the screen and fall into the collection container below, while the larger particles will remain on the screen. c. Repeat the screening process until the tea leaves are classified into the desired tea leaves.

3. The process for extracting tea essence powder from tea water extract according to claim 1, It is characterized in that The raw material processing includes washing and drying, The cleaning step involves washing the selected tea leaves with running water to remove dust and pesticide residues on the surface; The drying step is to dry the washed tea leaves to a suitable moisture content for easy handling. The specific steps of drying are as follows: A. Spread the washed tea leaves evenly on the tea drying rack or in the tea drying room; B. Control the temperature and humidity of the drying environment. The temperature of the drying environment should be controlled between 20-30℃, and the humidity should be maintained between 50%-70%. At the same time, direct sunlight and strong winds should be avoided to prevent the tea leaves from changing color or being damaged. C. Turn the tea leaves regularly to ensure that they are evenly dried. Be gentle when turning them to avoid damaging the shape and integrity of the tea leaves.

4. The process for extracting tea essence powder from tea water extract according to claim 1, It is characterized in that The cold extraction and concentration comprises cold extraction and concentration. The cold extraction process involves soaking the processed tea leaves in cold water, and gradually dissolving the soluble components in the tea leaves into the water through long-term soaking at low temperature. The concentration is mainly carried out by vacuum concentration method to remove water from the soaked tea juice to form a concentrated solution.

5. The process for extracting tea essence powder from tea water extract according to claim 4, It is characterized in that The temperature of the cold water during soaking is 5-10°C, the cold brewing time is 8-12 hours, and the ratio of tea to water during soaking is 1:50 or 1:

100.

6. The process for extracting tea essence powder from tea water extract according to claim 4, It is characterized in that During the concentration, a filter or a centrifuge is required to separate the tea soaked in cold water from the tea leaves, and then concentrate the tea juice after obtaining the clear tea juice.

7. The process for extracting tea essence powder from tea water extract according to claim 1, It is characterized in that The freeze drying is divided into pre-freezing and vacuum freeze drying. During the pre-freezing, the concentrated liquid is poured into a tray or a container and quickly frozen under low temperature conditions to form ice crystals. During the vacuum freeze drying, the frozen tea concentrate is placed in a vacuum freeze dryer, and the ice crystals are sublimated into water vapor by heating under vacuum and discharged, thereby obtaining dry tea essence powder.

8. The process for extracting tea essence powder from tea water extract according to claim 7, It is characterized in that During the pre-freezing, the concentrated liquid is pre-frozen at a low temperature of -25°C to -30°C, the cooling rate is controlled at 2-5°C / min, and the temperature is kept for 1-2 hours after reaching the temperature.

9. The process for extracting tea essence powder from tea water extract according to claim 7, It is characterized in that The vacuum cooling and drying is performed at -75°C and a vacuum environment within 5 Pa for up to 48 hours.

10. The process for extracting tea essence powder from tea water extract according to claim 1, It is characterized in that After the vacuum drying, the tea powder is dried again to remove trace moisture in the tea essence powder, and the drying temperature range is 10°C-35°C.

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