A food pretreatment device and method for food detection

Abstract

The application relates to the technical field of food detection pretreatment equipment, in particular to a food pretreatment device and method for food detection, wherein the device comprises a machine body, a controller, a centrifugal mechanism, a crushing mechanism, an oscillation mechanism and a nitrogen blowing mechanism are arranged on the machine body, a fixed cylinder is fixedly connected to the top of the machine body and located on one side of a base, an arc-shaped groove is formed in the inner wall of the fixed cylinder, a vertical sliding groove is communicated with the bottom of the arc-shaped groove, a supporting cylinder is slidably arranged in the fixed cylinder, a fixed block is fixedly connected to the outer sidewall of the supporting cylinder, the fixed block is slidably connected with the arc-shaped groove and the vertical sliding groove, a fixed box is fixedly connected to the top of the supporting cylinder, a cleaning assembly is arranged on the fixed box, and a collecting assembly is arranged on the machine body. The supporting cylinder is driven by an electric control rod to rotate and ascend and descend along the arc-shaped groove and the vertical sliding groove, the air needle is switched between a nitrogen blowing station and a cleaning station, the air needle head is high-pressure washed through the water outlet holes on the sleeve, cleaning and waste liquid collection are realized, and cross contamination is avoided.

Description

Technical Field

[0001] This invention relates to the field of food testing and pretreatment equipment technology, specifically to a food pretreatment device and method for food testing. Background Technology

[0002] In the field of food testing, sample pretreatment is a key preliminary step to ensure the accuracy and reliability of test results. Its core objective is to transform the complex food matrix into a state suitable for instrument analysis through a series of physical or chemical operations, effectively remove impurities, enrich the target analytes, and at the same time avoid the loss or deterioration of the target analytes during the processing.

[0003] With the rapid development of the food industry and the continuous improvement of food safety standards, the requirements for the accuracy and efficiency of food testing are becoming increasingly stringent, highlighting the importance of the pretreatment process. This has led to the development of diverse pretreatment methods and specialized equipment, such as the YT-QC4 integrated food pretreatment machine produced by Shandong Yuntang Intelligent Technology Co., Ltd. This machine mainly consists of a frame, centrifugation mechanism, oscillation mechanism, nitrogen blowing mechanism, and control system. It integrates multiple core functional modules such as centrifugation, oscillation, and nitrogen blowing, enabling it to complete multiple pretreatment operations for food samples in one stop, simplifying experimental procedures and improving work efficiency.

[0004] When using the YT-QC4 integrated food pretreatment machine to pretreat food samples, the high-speed airflow impacts the sample solution surface during nitrogen blowing, which can easily cause sample splashing. Some of the splashed sample will adhere to the tip of the gas needle. If the gas needle is not thoroughly cleaned before being used to process the next sample after nitrogen blowing of one sample, the components of the previous sample remaining on the gas needle will enter the next sample solution with the nitrogen blowing, mix with the target sample, and introduce cross-contamination, affecting the accuracy and reliability of the test results. The cleaning and maintenance process of the gas needle is usually done by wiping or washing them manually one by one, which may lead to repeated cross-contamination problems due to incomplete cleaning.

[0005] Therefore, the present invention proposes a food pretreatment device and method for food testing to solve the above problems. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a food pretreatment device and method for food testing. The device uses an electric control rod to drive a support cylinder to move up and down and rotate along an arc-shaped groove and a vertical slide, allowing the air needle to switch between a nitrogen blowing station and a cleaning station. The water outlet on the sleeve is used to perform high-pressure rinsing of the air needle tip, achieving cleaning and waste liquid collection, thereby avoiding cross-contamination.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows: A food pretreatment device for food testing includes a body, on which a controller, a centrifugation mechanism, a pulverizing mechanism, a oscillation mechanism, and a nitrogen blowing mechanism are provided. The nitrogen blowing mechanism includes a base embedded in the top of the body. The top of the base has several placement holes for placing sample tubes. A fixed cylinder located on one side of the base is fixedly connected to the top of the body. An electric control rod is fixedly connected to the bottom wall of the fixed cylinder and is electrically connected to the controller. An arc-shaped groove is formed on the inner wall of the fixed cylinder, and a vertical sliding groove is connected to the bottom of the arc-shaped groove. The vertical sliding groove is formed on the inner wall of the fixed cylinder. A support cylinder is slidably fitted inside the fixed cylinder. The output shaft of the electric control rod is connected to the support cylinder. The bottom is rotatably connected, and a fixing block corresponding to the arc groove is fixedly connected to the outer wall of the support cylinder. The fixing block slides in conjunction with both the arc groove and the vertical slide groove. A fixing box is fixedly connected to the top of the support cylinder. The fixing box is connected to a nitrogen source. A flow regulating valve is provided at the connection between the fixing box and the nitrogen source. The flow regulating valve is electrically connected to the controller. Several air needles corresponding to the placement holes are connected to the bottom of the fixing box. A cleaning component for cleaning the needle tips is provided on the fixing box. A collection component for collecting cleaning waste liquid after cleaning is provided on the machine body. During the descent of the support cylinder, when the fixing block descends from the top of the arc groove to the bottom of the arc groove, the support cylinder drives the fixing box to rotate from above the collection component to above the base.

[0008] The technical principles of the above solution are as follows: The sample tube is placed in the placement hole on the base. Then, the controller controls the electric control rod to drive the support cylinder to descend. During the descent of the support cylinder, the fixed block slides along the spiral trajectory of the arc groove. The fixed block drives the support cylinder to rotate, so that the support cylinder drives the fixed box and the gas needle to rotate from above the collection assembly to above the base. As the electric control rod drives the support cylinder to continue to descend, the fixed block enters the vertical slide groove from the bottom of the arc groove. The vertical slide groove limits the fixed block, so that the fixed block and the support cylinder descend vertically, thereby driving the gas needle to insert into the sample tube. Then, the nitrogen blowing flow rate is controlled by the flow regulating valve. After nitrogen blowing is completed on the sample in the sample tube, the support cylinder is raised by the electric control rod. The support cylinder slides upward along the vertical slide and the arc groove in sequence, so that the fixed box rotates from above the base to above the collection component during the rising process. Then the cleaning component cleans the needle tip of the gas needle to avoid sample residue on the surface of the gas needle during the nitrogen blowing process.

[0009] The above approach has the following beneficial effects: 1. This solution uses the lifting and lowering drive of the fixed box to clean the bottom of the gas needle, reducing the risk of sample adhering to the gas needle, thereby reducing the risk of sample being carried into the next sample, reducing cross-contamination, and improving the accuracy of food testing. 2. In this solution, the combination of the arc groove and the fixing block allows the fixing box to rotate towards the collection component during the upward process, so that the liquid cleaned by the cleaning component can be collected in the collection component, avoiding the liquid generated during cleaning from spilling onto the base and its surroundings and contaminating the base and sample tube.

[0010] Furthermore, the cleaning component includes a fixing ring coaxially mounted on the top of the fixed cylinder. A connecting plate is fixedly connected to the side of the fixing ring near the air needle. A rectangular plate corresponding to the fixed box is fixedly connected to the side of the connecting plate away from the fixing ring. Several holes corresponding to the air needles are opened on the rectangular plate. The air needles pass through the corresponding holes and extend to the bottom of the rectangular plate. A liquid-transfer chamber is opened inside the rectangular plate. The liquid-transfer chamber is connected to a water storage box. A water pump is installed at the connection between the water storage box and the liquid-transfer chamber. The water pump is connected to the controller signal. Symmetrically arranged telescopic rods are fixedly connected to the top of the connecting plate. The top of each telescopic rod is fixedly connected to the bottom of the fixed box. Several springs located between the telescopic rods are fixedly connected to the top of the connecting plate. The other end of each spring is fixedly connected to the bottom of the fixed box. Several sleeves corresponding to the air needles are fixedly connected to the bottom of the rectangular plate. Each sleeve has an annular cavity inside. The top of each annular cavity is connected to the liquid-transfer chamber. Several water outlet holes are opened on the inner sidewall of each sleeve. Each water outlet hole is connected to the corresponding annular cavity. The needles of the air needles are all located within the water outlet trajectory of the water outlet holes.

[0011] Beneficial effects: When the fixing block rises to contact the top of the arc-shaped groove, the fixing box is at its highest position and directly above the collecting component. At this time, under the elastic force of the spring, the connecting plate is pushed downward, which in turn drives the rectangular plate and the sleeve to descend to the position corresponding to the needle tip of the air needle, making cleaning easier. When the air needle descends with the fixing box and the support cylinder, the bottom of the fixing ring abuts against the top of the fixing cylinder. As the support cylinder and the fixing box descend, the spring is compressed, which drives the air needle to descend. At this time, the needle tip of the air needle separates from the sleeve, allowing the sleeve to be stored in the upper part of the air needle without affecting the nitrogen blowing operation. The high-pressure water jet from the water outlet forms a tangential impact with the surface of the needle tip, using the impact of the water jet to break up stubborn protein or lipid residues adhering to the surface of the needle tip. Furthermore, the reaction force of the water jet from the outlet is transmitted to the sleeve, and this reaction force is transmitted to the spring through the sleeve, rectangular plate, and connecting plate. The elastic deformation of the spring causes the rectangular plate and sleeve to vibrate irregularly, which in turn drives the outlet to move synchronously. This causes the sprayed cleaning water to change its impact angle in real time. The rapid change in the direction of the water flow generates alternating shear force, which continuously breaks down the adhesion interface between stubborn residues and the needle surface. At the same time, the pulsed water pressure fluctuations generated by the vibration enhance the ability of the water flow to peel off and disperse residues such as proteins and lipids, thereby improving the thoroughness of cleaning the air needle tip, reducing the risk of cross-contamination, and ensuring the accuracy and reliability of food testing results.

[0012] Furthermore, the collection component includes a collection box, the bottom of which is detachably connected to the top of the body, and a funnel detachably connected to the top of the collection box. When the fixing block moves to the top of the arc-shaped groove, the fixing box is located directly above the collection box.

[0013] Beneficial effects: The tilted waste liquid generated during cleaning is collected in the collection box. At the same time, the structure of the funnel with the large opening facing up and the small opening facing down prevents the waste liquid in the collection box from splashing onto the air needle and sleeve due to the dripping of new waste liquid, thus reducing the risk of secondary pollution.

[0014] Furthermore, all water outlets are designed with an inclined structure, with the side of the water outlet closest to the corresponding air needle higher than the other side.

[0015] Beneficial effects: The inclined water outlet allows water to flow from bottom to top onto the air needle, and some of the water flow is guided by the inclined water outlet to act directly on the inner wall of the air needle, thereby improving the cleaning coverage.

[0016] Furthermore, the diameter of the water outlet holes on the side closest to the corresponding air needle is smaller than that on the other side.

[0017] Beneficial effects: Utilizing the Venturi principle, water flows from the larger diameter end of the outlet hole to the smaller diameter end, creating a nozzle effect and improving cleaning intensity.

[0018] Furthermore, a pressure sensor is embedded in the top of the arc-shaped groove, and the pressure sensor is electrically connected to the controller.

[0019] Beneficial effects: When the fixed block rises to the top of the arc-shaped groove and applies pressure to the pressure sensor, the controller receives a pressure change signal, indicating that the air needle has moved directly above the collection box and the sleeve is located in the needle tip area of ​​the air needle. At this time, the controller controls the water pump to start working to clean the needle tip of the air needle.

[0020] Furthermore, each hole is equipped with a sealing ring.

[0021] Beneficial effects: By setting a sealing ring at the hole, it is ensured that during the cleaning process, the cleaning fluid will not splash upward from the gap between the hole and the air needle to the upper part of the fixing box or air needle, thereby avoiding contamination of other parts of the equipment by the cleaning fluid. At the same time, it also ensures that the cleaning fluid can act more concentratedly on the part of the air needle that extends into the sample tube, thus improving the cleaning effect.

[0022] Furthermore, a hot air blower is fixedly connected to the side wall of the collection box, and the air outlet of the hot air blower is connected to several air nozzles arranged along the circumference of the collection box. All air nozzles are fixedly connected to the top of the collection box.

[0023] Beneficial effect: By blowing hot air onto the air needle above the collection box through the air outlets set around the circumference of the collection box, the drying of the air needle tip is accelerated.

[0024] Furthermore, a touch screen is embedded in the top of the device, and the touch screen is electrically connected to the controller.

[0025] Beneficial effects: Operators can intuitively monitor the working status and parameter settings of each mechanism through the touch screen display.

[0026] Furthermore, a food pretreatment method for food testing includes the following steps: S1: Sample loading and initial positioning: The food sample to be processed is placed in the centrifugation mechanism, pulverization mechanism and oscillation mechanism to complete the corresponding centrifugation, pulverization and oscillation processes to obtain the processed sample solution; the sample tube containing the sample solution is placed in the placement hole, and the controller controls the fixing box and air needle to descend so that the air needle is located in the sample tube and the air needle tip is above the sample liquid surface. S2: Nitrogen blowing concentration treatment: After the position of the gas needle is determined, the nitrogen source is turned on, and the flow regulating valve is adjusted to the preset flow rate through the controller. After the nitrogen is distributed through the fixed box, it is blown to the surface of the sample solution by each gas needle to concentrate the sample solution by nitrogen blowing. S3: Nitrogen blowing end and cleaning switch: After nitrogen blowing concentration is completed, turn off the nitrogen source, and control the fixed box to drive the gas needle to rise and rotate to the top of the collection box. At this time, the sleeve is pushed by the spring force to be located in the needle tip area of ​​the gas needle. S4: Air Needle Cleaning and Waste Liquid Collection: After receiving a pressure signal, the controller controls the water pump to pump the cleaning solution in the water storage box into the liquid transfer chamber. The cleaning solution is sprayed onto the surface of the air needle tip through the liquid transfer chamber, the annular chamber, and the water outlet to rinse the residual sample attached to the needle tip. The waste liquid generated during rinsing drips downwards and is collected in the collection box through the funnel. After cleaning is completed, the controller controls the hot air blower to blow air onto the air needle to accelerate the evaporation of the cleaning solution.

[0027] Beneficial effects: By controlling the electric control rod to drive the support cylinder to rise and fall along the arc-shaped groove and vertical slide, the fixed box and air needle automatically switch between the nitrogen blowing station and the cleaning station, realizing a seamless connection between nitrogen blowing concentration and air needle cleaning. The entire process of raising, rotating, positioning and cleaning the air needle can be completed without manual intervention, improving pretreatment efficiency. When the fixed block rises to the top of the arc-shaped groove, it triggers the pressure sensor, which automatically starts the water pump to supply cleaning fluid to the water outlet of the sleeve, performing targeted high-pressure rinsing on the air needle tip to remove stubborn residues such as proteins and lipids that splashed and adhered during nitrogen blowing, avoiding cross-contamination. At the same time, the rinsing waste liquid is collected in the collection box through the funnel to prevent waste liquid from spilling and contaminating the base and the surrounding environment. With the help of the hot air blower, the cleaned air needle is dried with hot air to accelerate the evaporation of the cleaning fluid and ensure that the air needle remains clean and dry before the next use. This comprehensively ensures the accuracy and reliability of food testing results, simplifies the operation process, and reduces the labor intensity of manual cleaning and the risk of human error. Attached Figure Description

[0028] Figure 1 This is an isometric view of an embodiment of the food pretreatment device for food testing according to the present invention; Figure 2 This is a front sectional view of the fixed cylinder of an embodiment of the food pretreatment device for food testing according to the present invention; Figure 3 This is a front sectional view of the sleeve in an embodiment of the food pretreatment device for food testing according to the present invention; Figure 4 The appendix to the embodiments of the food pretreatment apparatus for food testing of the present invention is shown below. Figure 3 Detailed drawing at point A; Figure 5 This is a schematic diagram illustrating the steps of an embodiment of the food pretreatment method for food testing according to the present invention.

[0029] The reference numerals in the accompanying drawings of the instruction manual include: 1. Body; 2. Centrifuge mechanism; 3. Crushing mechanism; 4. Vibration mechanism; 5. Base; 6. Placement hole; 7. Fixing cylinder; 8. Electric control rod; 9. Arc groove; 10. Vertical slide groove; 11. Support cylinder; 12. Fixing block; 13. Fixing box; 14. Air needle; 15. Fixing ring; 16. Connecting plate; 17. Rectangular plate; 18. Telescopic rod; 19. Spring; 20. Sleeve; 21. Water outlet; 22. Collection box; 23. Funnel; 24. Hot air blower; 25. Touch screen display. Detailed Implementation

[0030] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0032] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0033] The following detailed description illustrates the specific implementation method:

[0034] Example 1

[0035] As attached Figure 1 As shown: A food pretreatment device for food testing includes a body 1, which is equipped with a controller, a centrifugal mechanism 2, a pulverizing mechanism 3, a shaking mechanism 4, and a nitrogen blowing mechanism. The controller, centrifugal mechanism 2, pulverizing mechanism 3, shaking mechanism, and nitrogen blowing mechanism are all designed with reference to the YT-QC4 integrated food pretreatment machine produced by Shandong Yuntang Intelligent Technology Co., Ltd. If the gas needle 14 is not thoroughly cleaned after nitrogen blowing treatment of one sample and is directly used for the treatment of the next sample, the components of the previous sample remaining on the gas needle 14 will enter the next sample solution with the nitrogen purging, causing cross-contamination and affecting the accuracy and reliability of the test results. To reduce the risk of cross-contamination caused by sample residue carried by the gas needle 14, as shown in the attached... Figure 1 Appendix Figure 2 and attached Figure 3As shown, the nitrogen blowing mechanism includes a base 5, which is embedded in the top of the body 1. The top of the base 5 has several placement holes 6 for placing sample tubes. A fixed cylinder 7 located on one side of the base 5 is bolted to the top of the body 1. An electric control rod 8 is bolted to the bottom wall of the fixed cylinder 7. The electric control rod 8 is electrically connected to a controller. The preferred model of the electric control rod 8 is the Shanghai Andite ANT-16 electric control rod 8. An arc-shaped groove 9 is formed on the inner wall of the fixed cylinder 7. The bottom of the arc-shaped groove 9 is connected to a vertical sliding groove 10, which is located within the fixed cylinder 7. On the inner wall, a support cylinder 11 is slidably fitted inside the fixed cylinder 7. The output shaft of the electric control rod 8 is rotatably connected to the bottom of the support cylinder 11. A fixing block 12 corresponding to the arc groove 9 is welded to the outer wall of the support cylinder 11. The fixing block 12 is slidably fitted with both the arc groove 9 and the vertical sliding groove 10. A fixing box 13 is fixedly connected to the top of the support cylinder 11 by bolts. The fixing box 13 is connected to a nitrogen source. A flow regulating valve is provided at the connection between the fixing box 13 and the nitrogen source. The flow regulating valve is electrically connected to the controller. The preferred model of the flow regulating valve is Burocco. The Series 3000 flow control valve has a fixed box 13 with several air needles 14 corresponding to the placement holes 6 at the bottom. The fixed box 13 is equipped with a cleaning component for cleaning the needle tips of the air needles 14. The body 1 is equipped with a collection component for collecting cleaning waste liquid after cleaning. During the descent of the support cylinder 11, when the fixed block 12 descends from the top of the arc groove 9 to the bottom of the arc groove 9, the support cylinder 11 drives the fixed box 13 to rotate from above the collection component to above the base 5. The top of the body 1 is embedded with a touch display 25, which is electrically connected to the controller. The preferred model of the touch display 25 is JUMO 705070 (4.3") touch display 25. Specifically, as shown in the attached document Figure 1 Appendix Figure 3 and attached Figure 4As shown, the cleaning assembly includes a fixing ring 15 coaxially mounted on the top of the fixing cylinder 7. The fixing cylinder 7 and the fixing ring 15 are slidably fitted together. A connecting plate 16 is bolted to the side of the fixing ring 15 near the air needle 14. A rectangular plate 17 corresponding to the fixing box 13 is bolted to the side of the connecting plate 16 away from the fixing ring 15. The rectangular plate 17 has several holes corresponding to the air needles 14 (each hole is equipped with a sealing ring to ensure that during the cleaning process, the cleaning fluid will not splash upwards from the gap between the hole and the air needle 14 to the fixing box 13 or the upper part of the air needle 14, thereby avoiding contamination of other parts of the equipment by the cleaning fluid). The air needles 14 all pass through the corresponding holes and extend to the bottom of the rectangular plate 17. A liquid-transfer chamber is opened in the rectangular plate 17, which is connected to a water storage box. A water pump is installed at the connection between the water storage box and the liquid-transfer chamber. The water pump is connected to the controller signal. The preferred model of the water pump is the Siwei SWP series. The pump is FDA certified. The top of the connecting plate 16 is bolted to a symmetrically arranged telescopic rod 18. The top of each telescopic rod 18 is bolted to the bottom of the fixed box 13. The top of the connecting plate 16 is bolted to a number of springs 19 located between the telescopic rods 18. The other end of each spring 19 is bolted to the bottom of the fixed box 13. The bottom of the rectangular plate 17 is welded to a number of sleeves 20 corresponding to the air needles 14. Each sleeve 20 has an annular cavity inside. The top of each annular cavity is connected to the liquid transfer cavity. Each sleeve 20 has a number of water outlet holes 21 on its inner sidewall. Each water outlet hole 21 is connected to the corresponding annular cavity. The needles of the air needles 14 are all located within the water outlet trajectory of the water outlet holes 21. Each water outlet hole 21 is set to an inclined structure. The side of the water outlet hole 21 closer to the corresponding air needle 14 is higher than the other side. The diameter of the water outlet hole 21 on the side closer to the corresponding air needle 14 is smaller than the other side. As attached Figure 1 As shown, the collection component includes a collection box 22. The bottom of the collection box 22 is detachably connected to the top of the body 1. A funnel 23 is detachably connected to the top of the collection box 22. When the fixing block 12 moves to the top of the arc groove 9, the fixing box 13 is located directly above the collection box 22.

[0036] The specific implementation process is as follows: During the pretreatment of food test samples, the food sample to be processed is first placed in the centrifuge mechanism 2, the pulverizing mechanism 3, and the oscillation mechanism 4 in sequence to complete centrifugal separation, mechanical pulverization, and oscillation mixing, so that the complex food matrix is ​​transformed into a uniform sample solution. Then, the sample tube containing the sample solution is accurately placed in the placement hole 6 of the base 5. At this time, the operator sends a start command to the controller through the touch display 25. The controller then controls the electric control rod 8 on the bottom wall of the fixed cylinder 7 to start. The output axis of the electric control rod 8 retracts downward and drives the support cylinder 11 to begin to descend. The fixing block 12 on the outer wall of the support cylinder 11 then moves along the fixed cylinder 7. The top of the arc-shaped groove 9 on the inner wall begins to slide downwards. As the fixed block 12 moves downwards guided by the arc-shaped groove 9, it rotates towards the base 5, thereby causing the support cylinder 11, the fixed box 13, and the air needle 14 to rotate synchronously towards the base 5. When the fixed block 12 slides to the bottom of the arc-shaped groove 9, it enters the vertical slide 10 connected to the arc-shaped groove 9. At this time, the vertical slide 10 limits the circumferential movement of the fixed block 12. The support cylinder 11 and the fixed box 13 stop rotating and begin to descend vertically until the fixed block 12 descends to contact the bottom of the vertical slide 10. At this time, the bottom end of the air needle 14 extends into the sample tube and remains above the sample liquid surface. After the gas needle 14 is positioned, the controller turns on the nitrogen source and adjusts the flow regulating valve at the connection between the fixing box 13 and the nitrogen source to the preset flow rate. The nitrogen is evenly distributed through the internal cavity of the fixing box 13 and then blown onto the sample solution surface by each gas needle 14. Utilizing the inertia and purging effect of nitrogen, the solvent in the sample solution evaporates rapidly, achieving concentration and enrichment of the target analyte. During the nitrogen blowing process, the high-speed airflow impacting the solution surface may cause some sample to splash and adhere to the needle tip of the gas needle 14. If not cleaned promptly, these residual samples will be blown into the new sample during subsequent processing of other samples. The sample solution could cause cross-contamination. Therefore, after nitrogen blowing concentration, the controller shuts off the nitrogen source and controls the electric control rod 8 to drive the support cylinder 11 to rise. The fixing block 12 first slides upward along the vertical slide groove 10, driving the gas needle 14 to be pulled out from the sample tube. When the fixing block 12 slides to the top of the vertical slide groove 10, it enters the arc groove 9 again and slides upward along it. Under the guidance of the arc groove 9, the support cylinder 11 and the fixing box 13 rotate synchronously towards the collection box 22. When the fixing block 12 moves to the top of the arc groove 9, the fixing box 13 is located directly above the collection box 22. At this time, the cleaning process is started. As the fixed box 13 rotates to be directly above the collection box 22, it gradually rises, reducing the downward pressure of the fixed box 13 on the spring 19. This releases the elastic potential energy of the spring 19, which in turn pushes the connecting plate 16 and the fixing ring 15 closer to the fixed cylinder 7, keeping the relative heights of the connecting plate 16 and the rectangular plate 17 constant. When the fixed box 13 reaches its highest height (i.e., the fixing block 12 moves to the top of the arc-shaped groove 9), the fixed box 13 and the air needle 14 are directly above the collection box 22, with the needle tip of the air needle 14 aligned with the water outlet trajectory of the water outlet 21. The controller then activates the water pump. The cleaning fluid in the water storage box is pumped into the liquid transfer chamber in the rectangular plate 17. Under the pressure of the water pump, the cleaning fluid flows into the annular cavity on the side wall of the sleeve 20, and then sprays out from the water outlet 21 on the inner side wall of the sleeve 20. The water outlet 21 is set with an inclined structure, and the diameter of the hole on the side closer to the air needle 14 is smaller than that on the other side. Utilizing the Venturi principle, the flow rate of the cleaning fluid increases significantly when it flows from the large diameter end to the small diameter end, forming a high-pressure jet. At the same time, the inclined angle allows the water flow to act on the outer and inner side walls of the air needle 14 simultaneously, achieving all-round cleaning. The high-pressure water flow impacts the surface of the air needle 14 needle tip, breaking up and peeling off the stubborn residues such as proteins and lipids that adhere to it. At the same time, the reaction force generated by the water jet is transmitted to the sleeve 20, and then to the spring 19 through the sleeve 20, the rectangular plate 17 and the connecting plate 16. This causes the spring 19 to undergo elastic deformation, which in turn causes the rectangular plate 17 and the sleeve 20 to vibrate irregularly. This causes the spray angle of the water outlet 21 to change in real time, forming an alternating shear force that continuously destroys the adhesion interface between the residual sample and the surface of the air needle 14, further improving the cleaning effect. The waste liquid generated during the cleaning process carries residual samples and drips downwards. It is collected by the funnel 23 at the top of the collection box 22 and then enters the collection box 22. The structure of the funnel 23 with the large opening facing upwards and the small opening facing downwards can prevent the waste liquid from splashing and avoid contaminating the gas needle 14, sleeve 20 and the surrounding environment. The bottom of the collection box 22 is detachably connected to the top of the machine body 1, which facilitates regular cleaning of the waste liquid and prevents bacterial growth. This reduces the risk of cross-contamination and ensures the accuracy and reliability of the test results.

[0037] Example 2

[0038] As attached Figure 2 As shown, the difference from Embodiment 1 is that a pressure sensor is embedded in the top of the arc-shaped groove 9. The pressure sensor is electrically connected to the controller. The preferred type of pressure sensor is the HELM HE91 pressure sensor. When the fixing block 12 rises to the top of the arc-shaped groove 9 and applies pressure to the pressure sensor, the controller receives a pressure change signal, indicating that the air needle 14 has moved directly above the collection box 22 and the sleeve 20 is located in the needle tip area of ​​the air needle 14. At this time, the controller controls the water pump to start working to clean the needle tip of the air needle 14.

[0039] Example 3

[0040] As attached Figure 1 As shown, the difference from Embodiment 2 is that a hot air blower 24 is fixedly connected to the side wall of the collection box 22 by bolts. The air outlet of the hot air blower 24 is connected to several air nozzles arranged around the circumference of the collection box 22. The air nozzles are all fixedly connected to the top of the collection box 22 by bolts. The preferred model of the hot air blower 24 is Guangzhou Xiangfeng HWG-X3A1 hot air blower 24. Hot air is blown onto the air needle 14 above the collection box 22 by the air nozzles arranged around the circumference of the collection box 22 to accelerate the drying of the needle tip of the air needle 14.

[0041] Example 4

[0042] As attached Figure 5 As shown, a food pretreatment method for food testing includes the following steps: S1: Sample loading and initial positioning: The food sample to be processed is placed in the centrifugation mechanism 2, the pulverizing mechanism 3 and the oscillation mechanism 4 to complete the corresponding centrifugation, pulverization and oscillation processes to obtain the processed sample solution; the sample tube containing the sample solution is placed in the placement hole 6, and the fixing box 13 and the air needle 14 are lowered by the controller so that the air needle 14 is located in the sample tube and the needle tip of the air needle 14 is above the sample liquid surface; S2: Nitrogen blowing concentration treatment: After the position of the gas needle 14 is determined, the nitrogen source is turned on, and the flow regulating valve is adjusted to the preset flow rate through the controller. After the nitrogen is distributed through the fixed box 13, it is blown to the surface of the sample solution by each gas needle 14 to concentrate the sample solution with nitrogen blowing. S3: Nitrogen blowing end and cleaning switch: After nitrogen blowing concentration is completed, the nitrogen source is turned off. The controller controls the fixed box 13 to drive the gas needle 14 to rise and rotate to the top of the collection box 22. At this time, the sleeve 20 is pushed by the elastic force of the spring 19 to make the sleeve 20 located in the needle area of ​​the gas needle 14. S4: Cleaning of the air needle 14 and collection of waste liquid: After receiving the pressure signal, the controller controls the water pump to pump the cleaning liquid in the water storage box into the liquid transfer chamber. The cleaning liquid is sprayed onto the surface of the air needle 14 through the liquid transfer chamber, the annular chamber and the water outlet 21 to rinse the residual sample attached to the needle. The waste liquid generated by rinsing drips down and is collected in the collection box 22 through the funnel 23. After cleaning is completed, the controller controls the hot air blower 24 to blow air onto the air needle 14 to accelerate the evaporation of the cleaning liquid.

[0043] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A food pretreatment device for food testing, comprising a body (1), wherein the body (1) is provided with a controller, a centrifugal mechanism (2), a pulverizing mechanism (3), a oscillation mechanism (4), and a nitrogen blowing mechanism, characterized in that: The nitrogen blowing mechanism includes a base (5), which is embedded in the top of the body (1). The top of the base (5) has several placement holes (6) for placing sample tubes. A fixed cylinder (7) located on one side of the base (5) is fixedly connected to the top of the body (1). An electric control rod (8) is fixedly connected to the bottom wall of the fixed cylinder (7). The electric control rod (8) is electrically connected to the controller. An arc groove (9) is opened on the inner wall of the fixed cylinder (7). A vertical sliding groove (10) is connected to the bottom of the arc groove (9). The vertical sliding groove (10) is opened on the inner wall of the fixed cylinder (7). A support cylinder (11) is slidably fitted inside the fixed cylinder (7). The output shaft of the electric control rod (8) is rotatably connected to the bottom of the support cylinder (11). A fixed block (12) corresponding to the arc groove (9) is fixedly connected to the outer wall of the support cylinder (11). 12) It slides with both the arc groove (9) and the vertical slide groove (10). The top of the support cylinder (11) is fixedly connected to the fixed box (13). The fixed box (13) is connected to the nitrogen source. The fixed box (13) is connected to the nitrogen source and is equipped with a flow regulating valve. The flow regulating valve is electrically connected to the controller. The bottom of the fixed box (13) is connected to several air needles (14) corresponding to the placement hole (6). The fixed box (13) is equipped with a cleaning component for cleaning the needle tip of the air needle (14). The body (1) is equipped with a collection component for collecting cleaning waste liquid after cleaning. During the descent of the support cylinder (11), when the fixed block (12) descends from the top of the arc groove (9) to the bottom of the arc groove (9), the support cylinder (11) drives the fixed box (13) to rotate from above the collection component to above the base (5).

2. The food pretreatment apparatus for food testing according to claim 1, characterized in that: The cleaning assembly includes a fixing ring (15) coaxially mounted on the top of the fixed cylinder (7). A connecting plate (16) is fixedly connected to the side of the fixing ring (15) near the air needle (14). A rectangular plate (17) corresponding to the fixed box (13) is fixedly connected to the side of the connecting plate (16) away from the fixing ring (15). Several holes corresponding to the air needle (14) are opened on the rectangular plate (17). The air needle (14) passes through the corresponding holes and extends to the bottom of the rectangular plate (17). A liquid transfer chamber is opened inside the rectangular plate (17). The liquid transfer chamber is connected to a water storage box. A water pump is provided at the connection between the water storage box and the liquid transfer chamber. The water pump is connected to the controller signal. Symmetrically arranged The telescopic rod (18) is fixedly connected to the bottom of the fixed box (13) at the top. The top of the connecting plate (16) is fixedly connected to several springs (19) located between the telescopic rods (18). The other end of the springs (19) is fixedly connected to the bottom of the fixed box (13). The bottom of the rectangular plate (17) is fixedly connected to several sleeves (20) corresponding to the air needles (14). The sleeves (20) have annular cavities inside. The top of the annular cavities are connected to the liquid transfer chamber. The inner sidewall of the sleeves (20) has several water outlet holes (21). The water outlet holes (21) are connected to the corresponding annular cavities. The needles of the air needles (14) are located within the water outlet trajectory of the water outlet holes (21).

3. The food pretreatment device for food testing according to claim 1, characterized in that: The collection component includes a collection box (22), the bottom of which is detachably connected to the top of the body (1), and a funnel (23) is detachably connected to the top of the collection box (22). When the fixing block (12) moves to the top of the arc groove (9), the fixing box (13) is located directly above the collection box (22).

4. The food pretreatment apparatus for food testing according to claim 2, characterized in that: All water outlets (21) are designed with an inclined structure, and the side of the water outlet (21) closest to the corresponding air needle (14) is higher than the other side.

5. The food pretreatment apparatus for food testing according to claim 4, characterized in that: The diameter of the water outlet (21) on the side closest to the corresponding air needle (14) is smaller than that on the other side.

6. The food pretreatment apparatus for food testing according to claim 1, characterized in that: A pressure sensor is embedded in the top of the arc-shaped groove (9), and the pressure sensor is electrically connected to the controller.

7. The food pretreatment apparatus for food testing according to claim 2, characterized in that: All holes are equipped with sealing rings.

8. The food pretreatment apparatus for food testing according to claim 3, characterized in that: A hot air blower (24) is fixedly connected to the side wall of the collection box (22). The air outlet of the hot air blower (24) is connected to several air nozzles arranged around the circumference of the collection box (22). All air nozzles are fixedly connected to the top of the collection box (22).

9. The food pretreatment apparatus for food testing according to claim 1, characterized in that: The top of the body (1) is embedded with a touch screen (25), which is electrically connected to the controller.

10. A food pretreatment method for food testing, operating based on the structure of the food pretreatment apparatus for food testing according to any one of claims 1-9, characterized in that, Includes the following steps: S1: Sample loading and initial positioning: After the food sample to be processed is placed in the centrifugation mechanism (2), the pulverizing mechanism (3) and the oscillation mechanism (4) to complete the corresponding centrifugation, pulverization and oscillation treatment, the processed sample solution is obtained; the sample tube containing the sample solution is placed in the placement hole (6), and the fixed box (13) and the air needle (14) are lowered by the controller so that the air needle (14) is located in the sample tube and the needle tip of the air needle (14) is above the sample liquid surface; S2: Nitrogen blowing concentration treatment: After the position of the gas needle (14) is determined, the nitrogen source is turned on, and the flow regulating valve is adjusted to the preset flow rate through the controller. After the nitrogen is distributed through the fixed box (13), it is blown to the surface of the sample solution by each gas needle (14) to concentrate the sample solution with nitrogen blowing. S3: Nitrogen blowing end and cleaning switch: After nitrogen blowing concentration is completed, turn off the nitrogen source and control the fixed box (13) to drive the gas needle (14) to rise and rotate to the top of the collection box (22) through the controller. At this time, the sleeve (20) is pushed by the elastic force of the spring (19) so that the sleeve (20) is located in the needle area of ​​the gas needle (14); S4: Cleaning of the air needle (14) and collection of waste liquid: After receiving the pressure signal, the controller controls the water pump to pump the cleaning liquid in the water storage box into the liquid transfer chamber. The cleaning liquid is sprayed onto the surface of the air needle (14) through the liquid transfer chamber, the annular chamber and the water outlet (21) to rinse the residual sample attached to the needle. The waste liquid generated by rinsing drips down and is collected in the collection box (22) through the funnel (23). After cleaning is completed, the controller controls the hot air blower (24) to blow air onto the air needle (14) to accelerate the evaporation of the cleaning liquid.

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