Device and method for efficiently extracting volatile organic compounds in compressed tea at low cost

Abstract

The invention discloses a device and method for efficiently extracting volatile organic compounds in compressed tea at low cost, and relates to the field of detection of volatile organic compounds in compressed tea, the upper surface of a mainframe box is provided with a bearing area and an air guide chamber, vent holes are formed in the bearing area, tea leaves are placed on the bearing area, and an air guide fan and a temperature control heating block are arranged in the air guide chamber; spraying holes are formed in the area, corresponding to target tea leaves, of the air guide chamber, and the lower end of the heat insulation shell is sealed with the upper surface of the mainframe box and wraps the tea leaves and the air guide chamber; the upper end of the wind scooper is communicated with the vent hole, the lower end of the wind scooper is communicated with an inlet of the air draft fan, and an adsorption column is arranged in the wind scooper. Air flows from the main machine box, pass through the air guide fan, are heated through the temperature control heating block and are sprayed out through the spraying holes to heat and spray tea samples. The sprayed airflow forms negative pressure through the exhaust fan and is intensively adsorbed to the adsorption column by the wind scooper, and the adsorbed airflow is blown into the mainframe box by the exhaust fan; the formed airflow circulation enables the tea sample to gradually rise to the set temperature, and finally efficient and low-cost extraction of the volatile organic compounds is completed.

Description

Technical Field

[0001] The invention relates to the field of volatile organic matter detection in compressed tea, in particular to a device and method for extracting volatile organic matter in compressed tea with high efficiency and low cost. Background Art

[0002] Tea is popular because of its health benefits. Chinese tea includes green tea, yellow tea, white tea, black tea, oolong tea, dark tea, as well as flower tea, compressed tea, tea bags and tea powder that are processed from the above teas. Compressed tea is a reprocessed tea, and its basic process is: tea leaves are screened, blended, steamed, pressed into shape, and dried. Common compressed teas include Fuzhuan tea, flower brick tea, black brick tea, green brick tea, rice brick tea, Tuo tea, etc. Different types of compressed tea undergo different degrees of microbial fermentation after being compressed into blocks during processing. Studies have shown that the water content of tea leaves and the temperature and humidity of the environment affect the growth and reproduction of microbial flora in compressed tea, thereby regulating various metabolites in compressed tea and ultimately affecting the quality of compressed tea. Aroma is one of the core factors of compressed tea quality, and its main material basis is various volatile organic compounds. By detecting and analyzing the volatile organic compounds in the finished compressed tea, the quality of the finished product can be judged. At the same time, since compressed tea undergoes different degrees of fermentation during processing, when process parameters such as tea moisture content, ambient temperature and humidity are abnormal, the quality of the tea may be damaged. Therefore, by collecting, detecting and analyzing the volatile organic compounds produced during the fermentation of compressed tea, it is helpful to determine whether the processing technology is normal. Gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) and gas chromatography-ion mobility spectrometry (GC-IMS) are commonly used methods for detecting volatile organic compounds in tea, which have the advantages of high sensitivity and accurate detection. However, since compressed tea has a compact texture and volatile organic compounds are often inside, the tea leaves need to be crushed for testing during analysis, which causes damage to the outer packaging and tea blocks of the compressed tea. Based on the above problems, the volatile organic compounds can be enriched on the volatile organic compound collection sheet by vacuuming, and then quickly inspected and tested by chromatography at a later time. Specifically, the compressed tea is tightly wrapped with an outer packaging, a first through hole is opened in the upper surface of the outer packaging, and a second through hole is opened in the lower surface of the outer packaging. The first through hole is filled with a volatile organic compound collection sheet that fits its own inner wall, and the second through hole is filled with a non-woven fabric that fits its own inner wall. The lower end of the exhaust hood is connected to the upper surface of the outer packaging, and the air inlet end of the vacuum equipment is sealed and connected to the air outlet end of the vacuum hood, and the air outlet end of the vacuum hood is connected to the volatile organic compound collection sheet. However, this method has two problems: first, the outer packaging is a whole, and the fermentation process of many teas is also carried out under the condition of outer packaging. Each outer packaging can only be used for a specific portion of tea, which is costly; second, the vacuum equipment needs to run for a long time to meet the detection standard, and the efficiency is low. Summary of the invention

[0003] In view of the problems existing in the prior art, the present invention proposes a device and method for extracting volatile organic compounds in compressed tea with high efficiency and low cost, so as to solve the problems of high cost and low efficiency of the current vacuum method. The volatile organic compounds in the compressed tea leaves can be extracted efficiently and losslessly, and the fermentation status inside the compressed tea can be known by detecting and analyzing the collected volatile organic compounds.

[0004] The present invention is achieved through the following technical solutions: A device for extracting volatile organic compounds from compressed tea with high efficiency and low cost, comprising a main box, a heat-insulating shell and an air guide cover; The upper surface of the main box is provided with a bearing area and an air guide chamber connected to the inner cavity of the main box, the bearing area is evenly provided with ventilation holes, the bearing area is used to place the target tea leaves, the air guide chamber is provided with an air guide fan and a temperature control heating block, the air guide chamber and the area corresponding to the target tea leaves are provided with spray holes, the lower end of the heat-insulating shell is sealed with the upper surface of the main box, and wraps the target tea leaves and the air guide chamber; The main chassis is provided with an exhaust fan, the upper end of the air guide cover is connected with the vent hole, and the lower end is connected with the inlet of the exhaust fan, and an adsorption column is arranged in the air guide cover.

[0005] A further improvement of the present invention is: A mounting opening is provided at the center of the upper surface of the main chassis, a carrying plate is arranged in the mounting opening, and ventilation holes are evenly provided on the carrying plate.

[0006] There are a plurality of air guide chambers in the shape of long strips with rectangular cross sections. The air guide chambers are evenly distributed around the target tea leaves in a direction perpendicular to the upper surface of the main housing.

[0007] The heat-insulating outer shell is made of transparent material and is in the shape of a cuboid. The lower end of the heat-insulating outer shell is sealed and plugged into the outer edge of the upper surface of the main box.

[0008] The lower end of the air guide chamber is fixedly plugged into the upper surface of the main chassis, the lower end surface of the air guide chamber is opened, and an air guide fan and a temperature-controlled heating block are arranged in the air guide chamber from bottom to top.

[0009] The air guide chamber is also provided with an air guide grid, which is located above the temperature control heating block, and the upper end surface of the air guide grid is located below one third of the height of the air guide chamber, and the spray hole is located above the air guide grid; The spray holes are arranged in a plurality of vertical rows and are evenly distributed along the length direction of the air guide chamber. The spray holes in each row are evenly distributed between the air guide grid and the upper end surface of the air guide chamber.

[0010] The air guide cover includes a truncated cone section and a cylindrical section of an integrated structure, the upper opening of the truncated cone section is larger than the lower opening, the inner diameter of the cylindrical section is larger than the lower opening of the truncated cone section and smaller than the upper opening of the truncated cone section, the bearing plate is circular, the diameter of the bearing plate is the same as the inner diameter of the upper opening of the truncated cone section, and the adsorption column is placed in the cylindrical section; The opening at the upper end of the truncated cone segment corresponds to the edge of the carrier plate, and the exhaust fan is placed in a box at the bottom center of the main chassis. The side walls of the box are provided with air flow holes, and a cylindrical stepped hole is provided at a position on the upper surface of the box corresponding to the adsorption column. The lower end face of the adsorption column is located in the stepped hole, and the lower end face of the cylindrical segment is placed on the upper surface of the box and has a spacing from the edge of the cylindrical stepped hole.

[0011] It also includes a cylindrical carrier arranged between the adsorption column and the cylindrical section. The upper end of the carrier is open and the lower end is provided with a vent hole. The carrier is inserted between the adsorption column and the cylindrical section from bottom to top, and the lower end surface of the carrier is engaged in the cylindrical stepped hole.

[0012] The inner diameter of the carrier is larger than the diameter of the adsorption column, the outer diameter of the carrier is equal to the inner diameter of the cylindrical section, the height of the carrier is smaller than the cylindrical section, and the vent holes form a circular through hole area at the center of the lower end of the carrier, and then are evenly spaced radially along the edges of the circular through hole area and the lower end of the carrier.

[0013] A method for extracting volatile organic compounds from compressed tea with high efficiency and low cost, based on any one of the above-mentioned devices for extracting volatile organic compounds from compressed tea with high efficiency and low cost, comprising the following steps: S1, according to the specific type of target tea, the heating temperature of the temperature-controlled heating block is set, and the air guide fan and the exhaust fan are turned on. The air flows from the main box, through the air guide fan, through the temperature-controlled heating block to be heated, and then sprayed out from the spray hole to heat and spray the target tea sample; S2, the airflow after spraying forms negative pressure through the exhaust fan, and is concentratedly adsorbed to the adsorption column by the air guide cover. The adsorbed airflow is blown into the main box by the exhaust fan; S3, continuing the airflow circulation formed by S1~S2, so that the target tea sample gradually rises to the set temperature, completing the efficient and low-cost extraction of volatile organic compounds in compressed tea.

[0014] Compared with the prior art, the present invention has the following beneficial technical effects: The present invention discloses a device for extracting volatile organic compounds from compressed tea with high efficiency and low cost. The airflow is heated from the main box through the air guide fan through the temperature-controlled heating block, and then sprayed out from the spray hole. Through such a heating and air guide design, the compressed tea placed on the bearing area is heated and blown by an airflow with a certain temperature without damaging the outer packaging of the compressed tea, and the release of relevant volatile organic compounds in the compressed tea blocks is promoted by increasing the temperature of the tea leaves. The sealing arrangement of the lower end of the heat-insulating shell and the upper surface of the main box and the wrapping of the target tea leaves and the air guide chamber can prevent the leakage of the target volatile organic compounds. During the exhaust process of the exhaust fan, the volatile organic compounds in the upper part are concentratedly adsorbed on the adsorption column; the air after adsorption is blown into the main box by the exhaust fan, and the target tea blocks are blown again after being guided and heated, so that the target tea sample can be gradually raised to the set temperature, and the cyclic enrichment of the tea blocks and the volatile organic compounds released by the tea leaves can be realized. The target tea blocks are heated by air flow to promote the release of related volatile organic compounds. Without affecting the appearance and integrity of the tea blocks, the volatile organic compounds are adsorbed on the adsorption column by a circulating enrichment method, which solves the problems of high cost and low efficiency of the current vacuum method. The volatile organic compounds in the compressed tea can be extracted efficiently and at low cost, making it easier to know the fermentation status inside the compressed tea blocks. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall model of the device described in the present invention.

[0016] Figure 2 The schematic diagram is a structural diagram of the device of the present invention without the heat-insulating shell.

[0017] Figure 3 This is a schematic diagram of the internal structure of the main box in the device of the present invention.

[0018] Figure 4 It is a schematic diagram of an angled section of the device of the present invention.

[0019] Figure 5 It is a schematic cross-sectional view from another angle of the device of the present invention.

[0020] Figure 6 for Figure 2 Schematic diagram of the structure of the central air guide chamber.

[0021] Figure 7 for Figure 6 Schematic cross-section diagram of .

[0022] Figure 8 for Figure 2 Schematic diagram of the carrier structure in .

[0023] Fig. 9 for Figure 4Schematic cross-sectional view of the composite structure of the central air guide hood, adsorption column and carrier.

[0024] Fig.10 for Figure 5 Schematic diagram of the cross section of the main chassis.

[0025] Fig.11 It is a schematic diagram of the flow path of the airflow direction when the device of the present invention is in operation.

[0026] In the figure: 101 - heat-insulating shell, 102 - main chassis, 103 - air guide chamber, 104 - carrying plate, 105 - target tea leaves, 106 - air guide cover, 107 - adsorption column, 108 - carrier, 1021 - exhaust fan, 1022 - air guide chamber mounting hole, 1031 - spray hole, 1032 - air guide fan, 1033 - temperature-controlled heating block, 1034 - air guide grille, 1081 - vent. DETAILED DESCRIPTION

[0027] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, which are intended to explain the present invention rather than to limit it.

[0028] The invention discloses a device for extracting volatile organic compounds in compressed tea with high efficiency and low cost, which can extract the volatile organic compounds in the compressed tea in a targeted manner and circulate and enrich the volatile organic compounds in an adsorption column to facilitate subsequent detection.

[0029] like Figure 1 and Figure 2 As shown, the heat-insulating shell 101 and the main box 102 are the main components of the device; the heat-insulating shell 101 is made of a transparent material with good heat-insulating properties, such as polymethyl methacrylate or polycarbonate, and is in the shape of a cuboid. The lower end of the heat-insulating shell 101 is sealed and plugged into the outer edge of the upper surface of the main box 102, wrapping the target tea leaves 105 and the air guide chamber 103, so that the device can achieve internal circulation airflow and prevent the target volatile organic compounds from leaking. Figure 3 As shown, the upper surface of the main case 102 is provided with a bearing area and an air guide chamber 103 connected to the inner cavity of the main case 102, ventilation holes are evenly opened in the bearing area, and the target tea leaves 105 are placed on the bearing area. Specifically, an air guide chamber installation hole 1022 for installing the air guide chamber 103 and an installation opening of the carrying plate 104 are opened in the center of the upper surface of the main case 102, and the carrying plate 104 is installed in the installation opening. The carrying plate 104 is evenly provided with ventilation holes, and the target tea leaves 105 are placed on the carrying plate 104. An air guide fan 1032 and a temperature control heating block 1033 are provided in the air guide chamber 103, and a plurality of spray holes 1031 for facilitating the spraying of airflow are opened in the area of ​​the air guide chamber 103 corresponding to the target tea leaves 105, so that the heated airflow in the air guide chamber 103 can be blown onto the target tea leaves 105. As shown Figure 4As shown, an exhaust fan 1021 is provided below the carrier plate 104 in the main chassis 102 to form a circulating airflow to facilitate the adsorption and collection of volatile organic matter in the adsorption column 107. The upper end of the air guide cover 106 is connected to the vent hole, and the lower end thereof is connected to the inlet of the exhaust fan 1021. The air guide cover 106 is arranged with an adsorption column 107, and the adsorption column 107 is composed of a high-transmittance membrane and activated carbon or resin wrapped therein.

[0030] In some specific implementation cases, there are four air guide chambers 103 , which are in the shape of long strips with rectangular cross-sections, and are evenly distributed around the target tea leaves 105 in a direction perpendicular to the upper surface of the main housing 102 .

[0031] like Figure 5 and Figure 7 As shown, the lower end of the air guide chamber 103 is fixedly plugged into the upper surface of the main chassis 102, the lower end surface of the air guide chamber 103 is open, and air guide fans 1032 ( Figure 7 The air guide grille 1034 in the air guide chamber 103 is located above the temperature control heating block 1033, the upper end surface of the air guide grille 1034 is located below one third of the height of the air guide chamber 103, and the spray hole 1031 is located above the air guide grille 1034. Figure 6 As shown, the spray holes 1031 are arranged in a plurality of vertical rows and are evenly distributed along the length direction of the air guide chamber 103. Figure 7 The spray holes 1031 in each column are evenly distributed between the air guide grille 1034 and the upper end surface of the air guide chamber 103. The air guide fan 1032, the temperature control heating block 1033 and the air guide grille 1034 are an integral structure with the air guide chamber 103. The air guide grille 1034 can be used to hold dust and other particulate impurities to prevent them from falling on the temperature control heating block 1033. The air flow is introduced from the lower 1032, and after being heated by the temperature control heating block 1033, it is rectified by the air guide grille 1034 to form a uniform intensity. The impurities are blown up and taken out, and finally sprayed out from the spray holes 1031, which acts similarly to a heater.

[0032] like Fig. 9 As shown, the air guide cover 106 includes a truncated cone section and a cylindrical section of an integrated structure. The upper opening of the truncated cone section is larger than the lower opening. The inner diameter of the cylindrical section is larger than the lower opening of the truncated cone section and smaller than the upper opening of the truncated cone section. Accordingly, the carrier plate 104 needs to be circular, and the diameter of the carrier plate 104 is the same as the inner diameter of the upper opening of the truncated cone section. The adsorption column 107 is placed in the cylindrical section. Fig.10As shown, the opening at the upper end of the truncated cone segment can correspond to the edge of the carrier plate 104, and the exhaust fan 1021 is specifically placed in a box at the bottom center of the main chassis 102. The side walls of the box are evenly provided with air flow holes, and a cylindrical stepped hole is provided at a position on its upper surface corresponding to the adsorption column 107. The lower end face of the adsorption column 107 is fixed in the stepped hole. At this time, the lower end face of the cylindrical segment is placed on the upper surface of the box, and a distance is left from the edge of the cylindrical stepped hole.

[0033] like Figure 8 As shown, the upper end of the carrier 108 is open, and the lower end is provided with a plurality of vent holes 1081, a portion of which is surrounded by a circular through hole area at the center of the lower end of the carrier 108, and the remaining vent holes 1081 are evenly spaced radially behind the circular through hole area and the edge of the lower end of the carrier 108. The carrier 108 is inserted between the adsorption column 107 and the cylindrical section from bottom to top, and the height of the carrier 108 is smaller than the cylindrical section, so the adsorption column 107 is installed on the carrier 108, and the lower end surface of the carrier 108 is engaged in the cylindrical stepped hole. The inner diameter of the carrier 108 is larger than the diameter of the adsorption column 107, and the outer diameter of the carrier 108 is equal to the inner diameter of the cylindrical section, so that a gap is left between the adsorption column 107 and the carrier 108. The air guide cover 106 is installed on the adsorption column 107 and the carrier 108 from top to bottom, forming a composite structure consisting of the air guide cover 106, the adsorption column 107 and the carrier 108 to ensure that the airflow flows from top to bottom and the airflow does not leak outward.

[0034] like Fig.10 and Fig.11 As shown, the exhaust fan 1021 installed in the main chassis 102 can effectively form a negative pressure environment, so that the airflow is forced from top to bottom by the air guide cover 106 through the adsorption column 107 and finally enters the space inside the main chassis 102, and is sucked in by the air guide fan 1032 in the air guide chamber 103, heated to a specified temperature by the temperature-controlled heating block 1033, and finally sprayed out from the spray hole 1031 to achieve the circulation of internal airflow and the adsorption and collection of volatile organic compounds.

[0035] The present invention discloses a device for extracting volatile organic compounds from compressed tea with high efficiency and low cost. Taking the extraction and collection of volatile substances in the processing of wolfberry leaf Fu brick tea as an example, the specific process is as follows: Since wolfberry leaf Fu brick tea needs to be aged at 50-60℃ after fermentation, considering the detection efficiency and tea quality, 65℃ was selected as the extraction temperature. This temperature can effectively promote the volatilization of related organic matter in the tea, and at the same time, it can also keep the related organic matter in a relatively stable state to prevent its decomposition due to excessively high temperature.

[0036] Step 1: Take the target tea sample 105 and place it on the carrier plate 104. Figure 3, open the box cover on the side of the main box 102, assemble and install the air guide cover 106, adsorption column 107 and carrier 108 in place, close the box cover of the main box 102, and install the heat insulating shell 101 on the outer edge of the upper surface of the main box 102. Step 2, set the temperature of the temperature-controlled heating block 1033 in the air guide chamber 103 to 65°C, turn on the air guide fan 1032 and the exhaust fan 1021, and then the circulation in the device starts. The airflow from the main box 102 passes through the air guide fan 1032 upward through the temperature-controlled heating block 1033 and is heated to 65°C. After being rectified by the air guide grille 1034, it is sprayed out from the spray hole 1031 to heat and spray the target tea sample 105, so as to facilitate the collection of volatile organic compounds.

[0037] Step 3, the airflow forms negative pressure through the exhaust fan 1021, and is concentratedly adsorbed to the adsorption column 107 by the wind guide cover 106. The adsorbed airflow passes through the vent 1081 set below the carrier 108 and is blown into the main chassis 102 by the exhaust fan 1021.

[0038] Repeat steps 2 and 3 above. After the target tea sample 105 gradually rises to the ambient temperature of 65° C. in the device within a set period of 2-3 hours, the volatile organic compounds can be adsorbed and collected on the adsorption column 107 for subsequent steps.

[0039] The adsorption column is used for sample pretreatment according to the relevant GC-IMS detection pretreatment method, and then conventional content analysis is performed. The specific operation process is as follows: The adsorption column was loaded into the sample tube and placed in the thermal desorber. The thermal desorber program was set to the hot trap set temperature (80°C) and the cold trap set temperature was increased from -30°C to 80°C. The injection needle temperature was 85°C, the injection volume was 500 μL, and the carrier gas was high-purity N 2 (Purity ≥ 99.999%), enter the chromatographic column in splitless mode for trace analysis.

[0040] The original tea samples of the control group were subjected to the experiment using the headspace sampling method, and the specific operation process is as follows: Headspace injection: 1.00 g tea sample was accurately weighed and placed in a 20 mL headspace bottle. The bottle was sealed and injected. The sample was incubated at 80 °C and 500 r / min for 15 min. The headspace injection needle temperature was 85 °C, the injection volume was 500 μL, and the carrier gas was high-purity N 2 (Purity ≥ 99.999%), enter the chromatographic column in splitless mode for trace analysis.

[0041] A total of 60 volatile organic compounds were collected and detected by the method of the present invention, including 20 aldehydes. A total of 62 volatile organic compounds were collected and detected by the traditional tea headspace sampling method, including 22 aldehydes as shown in Table 1, of which (Z)-4-heptenal and 2-methylacrolein were detected by the latter, and the rest were shown in Table 2, which proves that the present method has good collection and detection performance.

[0042] Table 1 Aldehyde substances

[0043] Table 2 Other substances

[0044] Furthermore, if the purity of the collected volatile substances that are easily oxidized needs to be improved, after the box cover of the main box 102 and the heat-insulating shell 101 are closed, an air inlet and an air outlet can be opened, and the air in the device can be evacuated to exhaust the air first, and then nitrogen can be introduced, which is conducive to the retention of volatile substances that are easily oxidized in the air on the adsorption column 107, thereby improving the purity of the collection. Taking the targeted extraction of lipid compounds in compressed tea as an example, the representative fats, phospholipids, glycerolipids, sugar esters and thioesters are often prone to oxidation reactions, so the above-mentioned nitrogen introduction method can be used when extracting such compounds.

Claims

1. A device for extracting volatile organic compounds from compressed tea with high efficiency and low cost, characterized in that: It comprises a main box (102), a heat-insulating housing (101) and an air guide cover (106); The upper surface of the main box (102) is provided with a bearing area and an air guide chamber (103) connected to the inner cavity of the main box (102); ventilation holes are evenly arranged in the bearing area; the bearing area is used to place the target tea leaves (105); an air guide fan (1032) and a temperature control heating block (1033) are arranged in the air guide chamber (103); a spray hole (1031) is arranged in the area of ​​the air guide chamber (103) corresponding to the target tea leaves (105); the lower end of the heat-insulating outer shell (101) is sealed with the upper surface of the main box (102) and wraps the target tea leaves (105) and the air guide chamber (103); An exhaust fan (1021) is provided in the main chassis (102); the upper end of the air guide cover (106) is connected to the vent hole, and the lower end is connected to the inlet of the exhaust fan (1021); and an adsorption column (107) is arranged in the air guide cover (106).

2. The device for extracting volatile organic compounds from compressed tea with high efficiency and low cost according to claim 1, characterized in that: A mounting opening is provided at the centre of the upper surface of the main chassis (102), a carrying plate (104) is arranged in the mounting opening, and ventilation holes are evenly provided on the carrying plate (104).

3. The device for extracting volatile organic compounds from compressed tea with high efficiency and low cost according to claim 2 is characterized in that: There are a plurality of air guide chambers (103) in the shape of long strips with a rectangular cross section. The air guide chambers (103) are evenly distributed around the target tea leaves (105) in a direction perpendicular to the upper surface of the main housing (102).

4. The device for extracting volatile organic compounds from compressed tea with high efficiency and low cost according to claim 3 is characterized in that: The heat-insulating outer shell (101) is made of a transparent material and is in the shape of a rectangular parallelepiped. The lower end of the heat-insulating outer shell (101) is sealed and plugged into the outer edge of the upper surface of the main box (102).

5. The device for extracting volatile organic compounds from compressed tea with high efficiency and low cost according to claim 3, characterized in that: The lower end of the air guide chamber (103) is fixedly plugged into the upper surface of the main chassis (102), the lower end surface of the air guide chamber (103) is opened, and an air guide fan (1032) and a temperature control heating block (1033) are arranged in the air guide chamber (103) from bottom to top.

6. The device for extracting volatile organic compounds from compressed tea with high efficiency and low cost according to claim 5, characterized in that: An air guide grille (1034) is also provided in the air guide chamber (103), the air guide grille (1034) is located above the temperature control heating block (1033), the upper end surface of the air guide grille (1034) is located below one third of the height of the air guide chamber (103), and the spray hole (1031) is located above the air guide grille (1034); The spray holes (1031) are arranged in a plurality of vertical rows and are evenly distributed along the length direction of the air guide chamber (103); the spray holes (1031) in each row are evenly distributed between the air guide grille (1034) and the upper end surface of the air guide chamber (103).

7. The device for extracting volatile organic compounds from compressed tea with high efficiency and low cost according to claim 6, characterized in that: The air guide cover (106) comprises a truncated cone section and a cylindrical section of an integral structure, the upper opening of the truncated cone section is larger than the lower opening, the inner diameter of the cylindrical section is larger than the lower opening of the truncated cone section and smaller than the upper opening of the truncated cone section, the supporting plate (104) is circular, the diameter of the supporting plate (104) is the same as the inner diameter of the upper opening of the truncated cone section, and the adsorption column (107) is placed in the cylindrical section; The opening at the upper end of the truncated cone section corresponds to the edge of the carrier plate (104); the exhaust fan (1021) is placed in a box at the bottom center of the main box (102); the side walls of the box are provided with air flow holes; a cylindrical stepped hole is provided at a position on the upper surface of the box corresponding to the adsorption column (107); the lower end surface of the adsorption column (107) is located in the stepped hole; the lower end surface of the cylindrical section is placed on the upper surface of the box and is spaced apart from the edge of the cylindrical stepped hole.

8. The device for extracting volatile organic compounds from compressed tea with high efficiency and low cost according to claim 7, characterized in that: It also includes a cylindrical carrier (108) arranged between the adsorption column (107) and the cylindrical section, the upper end of the carrier (108) is open, and the lower end is provided with a vent hole (1081), the carrier (108) is inserted between the adsorption column (107) and the cylindrical section from bottom to top, and the lower end surface of the carrier (108) is engaged in the cylindrical stepped hole.

9. The device for extracting volatile organic compounds from compressed tea with high efficiency and low cost according to claim 8, characterized in that: The inner diameter of the carrier (108) is greater than the diameter of the adsorption column (107), the outer diameter of the carrier (108) is equal to the inner diameter of the cylindrical section, the height of the carrier (108) is less than the cylindrical section, and the vent holes (1081) form a circular through hole area at the center of the lower end of the carrier (108), and are then evenly spaced radially at the edge of the circular through hole area and the lower end of the carrier (108).

10. A method for extracting volatile organic compounds from compressed tea with high efficiency and low cost, based on the device for extracting volatile organic compounds from compressed tea with high efficiency and low cost as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: S1, according to the specific type of the target tea leaves (105), the heating temperature of the temperature-controlled heating block (1033) is set, and the air guide fan (1032) and the exhaust fan (1021) are turned on, so that the air flows from the main box (102), through the air guide fan (1032), through the temperature-controlled heating block (1033), and is heated, and then sprayed out from the spray hole (1031), so as to heat and spray the target tea sample (105); S2, the airflow after spraying forms a negative pressure through the exhaust fan (1021), and is concentratedly adsorbed to the adsorption column (107) by the air guide cover (106), and the adsorbed airflow is blown into the main box (102) by the exhaust fan (1021); S3, continuing the airflow circulation formed by S1~S2, so that the target tea sample (105) gradually rises to the set temperature, completing the efficient and low-cost extraction of volatile organic compounds in the compressed tea.

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