Food safety pretreatment and detection device and method

Abstract

The invention discloses a food safety pretreatment and detection device and method, and relates to the technical field of food detection.The device comprises a box body, a control module, a pretreatment module and an ATP biological fluorescence detector, the control module is integrated on the box body, and the pretreatment module is integrated on the box body; the control module comprises a microcomputer control system, a visual operation panel, a nixie tube display and a key regulator; the pretreatment module comprises a concentrator for purging and concentrating a sample, a centrifugal machine for separating the sample, a uniform mixing instrument for uniformly mixing the sample and a water bath kettle for performing constant-temperature incubation on the sample; the ATP biological fluorescence detector is integrated in the box body and is used for carrying out microbial pollution detection on the food contact surface; the control module is suitable for adjusting and controlling operation parameters through the key adjuster when any unit in the concentrator, the centrifugal machine, the blending instrument or the water bath kettle operates, and the operation parameters are displayed on the visual operation panel in real time. The invention further provides a detection method, and on-site, rapid and intelligent food safety detection is achieved.

Description

Technical Field

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

[0002] Food safety testing is a crucial link in safeguarding public health, typically comprising two main stages: sample pretreatment and instrumental analysis. Sample pretreatment is the core step affecting testing efficiency and accuracy, aiming to separate, purify, and enrich the target analyte from the complex food matrix to eliminate interference and improve detection sensitivity. Traditional sample pretreatment processes rely on a series of separate, large-scale devices, such as nitrogen blowers for concentration, centrifuges for separation, vortex mixers for mixing, and water baths for heating.

[0003] This decentralized processing model suffers from numerous technical shortcomings and has become a bottleneck restricting the development of rapid on-site detection. Specifically, existing technologies mainly have the following problems: The equipment is scattered, the operation is cumbersome, and the efficiency is low: For example, patent application CN217931031U discloses a sample pretreatment device for food testing, which only integrates grinding and filtration functions, while key steps such as concentration and centrifugation still rely on other independent equipment. Operators need to transfer samples between different devices, which is cumbersome and time-consuming. This not only significantly increases the risk of sample contamination and loss, but also greatly limits the realization of high-throughput detection and cannot meet the stringent timeliness requirements of rapid on-site testing.

[0004] Low levels of automation and intelligence, and significant human error: Existing equipment relies heavily on manual setting and monitoring for parameters such as temperature control, time setting, and speed adjustment, lacking precise feedback control and fault diagnosis capabilities. For example, patent application CN214514692U relates to an intelligent constant temperature water bath, which achieves precise temperature control for a single device, but does not solve the problem of coordinated control and process integration with other pretreatment steps (such as centrifugation and oscillation). The operator's experience directly affects the reproducibility and accuracy of the results, and the inability to adjust parameters in real time during operation necessitates shutdown, further reducing efficiency.

[0005] Limited functionality and lack of integrated detection modules: Current market products and patented technologies mostly focus on pretreatment functions. Processed samples still need to be transferred to specialized detection equipment (such as spectrophotometers, chromatographs, etc.) for analysis. This transfer process introduces the risk of cross-contamination and sample loss again, prolonging the total time from sample to result (TAT) and failing to realize the true "sample in - result out" on-site rapid detection concept. Summary of the Invention

[0006] In view of this, the primary objective of the present invention is to overcome the aforementioned deficiencies of the prior art and provide a food safety pretreatment and testing device and method to at least solve the technical problems of dispersed equipment, poor portability, and low degree of automation in the prior art, thereby realizing on-site, rapid, and intelligent food safety testing.

[0007] To address the aforementioned problems, the first objective of this invention is to provide a food safety pretreatment and testing apparatus, comprising: Box; The control module is integrated on the housing. The control module includes a microcomputer control system and a visual operation panel, a digital tube display and a button regulator that are electrically connected to the microcomputer control system. The pretreatment module, integrated inside the housing, includes a concentrator for sample purge and concentration, a centrifuge for sample separation, a homogenizer for sample mixing, and a water bath for constant-temperature sample incubation; and An ATP biofluorescence detector is integrated inside the housing and is used to detect microbial contamination on food contact surfaces. The control module is adapted to adjust and control the corresponding operating parameters through the button regulator when any of the units in the concentrator, centrifuge, mixer or water bath is running, and the parameters are displayed in real time on the visual operation panel.

[0008] Preferably, the system further includes an intelligent temperature control system integrated into the concentrator and / or the water bath. The intelligent temperature control system includes a temperature detector, a heating actuator, a cooling actuator, and a PID temperature controller. The heating actuator and the cooling actuator are electrically connected to the PID temperature controller. The temperature detector is used to collect the actual temperature of at least one functional module in the pretreatment module in real time and output a temperature signal. The PID temperature controller is used to compare the actual temperature with a preset target temperature and output a heating control signal and / or a cooling control signal based on a PID algorithm. The heating actuator is used to receive the heating control signal and perform a heating operation on the functional module. The cooling actuator is used to receive the cooling control signal and perform a cooling operation on the functional module.

[0009] Preferably, the concentrator includes: The base has a plurality of first heating holes extending vertically on its upper surface. The first heating holes are evenly distributed on the same circumference and their diameters match the outer diameter of the centrifuge tube. A gas box is located above the first heating hole and is coaxially arranged with each of the first heating holes. The lower surface of the gas box is provided with gas needles that correspond one-to-one with the multiple first heating holes. The gas needles are used to deliver gas into the inner cavity of the centrifuge tube. An electric lifting mechanism is fixed at one end to the base and connected to the air box at the other end. The electric lifting mechanism is adapted to drive the air box to make linear motion in the vertical direction in order to adjust the depth of the air needle inserted into the centrifuge tube. An air pump is built into and fixed inside the base, and the air outlet of the air pump is connected to the air inlet of the air box through a gas pipeline.

[0010] Preferably, the temperature detector is a first temperature sensor disposed near the first heating hole, the first temperature sensor being used to detect the temperature of the first heating hole in real time and output a temperature signal; the heating actuator is an electric heating wire embedded in the base and arranged around each of the first heating holes, used to adjust the temperature of each of the first heating holes.

[0011] Preferably, the water bath includes a pot body with an opening at the top forming a constant temperature water bath chamber. The water bath chamber is provided with a plurality of vertically downward centrifuge tube racks, and the centrifuge tube racks are adapted to place positioning centrifuge tubes. The heating actuator is an electric heater fixed to the lower part of the pot body and arranged around the water bath cavity. The electric heater is used to heat the liquid in the water bath cavity to a set temperature. The temperature detector is a second temperature sensor inserted into the water bath and arranged adjacent to the centrifuge tube rack. The second temperature sensor is used to detect the liquid temperature in real time and output a temperature signal.

[0012] Preferably, the system further includes a fault self-diagnosis system electrically connected to the microcomputer control system. The fault self-diagnosis system is used to monitor the operating status of the centrifuge in real time, and to perform automatic deceleration and shutdown and alarm operations when overspeed, speed loss or imbalance faults are detected.

[0013] Preferably, the centrifuge includes: A centrifuge chamber is formed on the box body and is provided with an openable and closable centrifuge cover; A brushless DC motor is fixed to the bottom of the centrifuge chamber, and the output shaft of the brushless DC motor extends vertically upward into the centrifuge chamber; The rotor is detachably mounted on the output shaft. The rotor has multiple evenly distributed centrifuge tube positions, and the axis of each centrifuge tube position forms a fixed angle with the axis of the output shaft, so as to accommodate multiple centrifuge tubes at the same time. The speed control module is electrically connected to the brushless DC motor and is used to steplessly adjust and stabilize the speed of the output shaft. The timing module is electrically connected to the speed control module, and the timing module is used to send a stop signal to stop the brushless DC motor from rotating.

[0014] Preferably, the mixer comprises: The base has an interface for mounting on its upper surface; A drive motor is fixed inside the base. The output end of the drive motor is connected to an eccentric shaft, which is used to generate track oscillation with a rotation diameter of 4 mm. The top end of the eccentric shaft is rigidly connected to the bottom of the cavity of the mounting interface to directly transmit the oscillation power to the mounting interface. A speed control module is electrically connected to the drive motor, and the speed control module is used to steplessly adjust and maintain the set speed of the drive motor.

[0015] Preferably, the ATP bioluminescence detector includes: The housing has a dark chamber inside, and the top of the dark chamber has an openable and closable light-shielding cover and forms an insertion hole that is adapted to the outer diameter of a standard test tube. A photoelectric sensing module is installed at the bottom of the dark chamber. The photoelectric sensing module includes a photon counting photomultiplier tube and a sampling cavity coupled thereto. It is used to detect the fluorescence signal emitted by the reaction per unit time and output an RLU value proportional to the ATP content. A biofluorescent reagent holder is located on the upper surface of the housing to fix a disposable reagent card pre-loaded with luciferase / luciferin reagent, allowing the reagent and sample to mix instantaneously in the sampling chamber; A microcontroller is electrically connected to the photoelectric sensing module. The microcontroller is used to display the RLU value on the visual operation panel and execute the coliform bacteria screening algorithm. When the RLU value exceeds a preset threshold, a positive prompt is output. A memory, connected to the microcontroller bus, is used to store the detection result records; A USB interface is located on the side wall of the housing and electrically connected to the microcontroller, used to export the detection results recorded in the memory to an external computer.

[0016] A second objective of this invention is to provide a food safety pretreatment and detection method based on the aforementioned apparatus, comprising the following steps: S1: Sample Preparation The food samples to be tested were preliminarily processed and packaged; S2: Concentration Process The control module sets and adjusts the concentration temperature, airflow speed and concentration time in real time according to the solvent properties and volume. It uses the air pump and electric heating wire built into the concentrator to purge and concentrate the sample, and optimizes the concentration process through an electric lifting mechanism. S3: Centrifugal stratification Set the target relative centrifugal force value, automatically calculate and execute the corresponding rotation speed, and use a centrifuge to separate the sample; S4: Oscillate and mix The sample was mixed by vortexing using a mixer. S5: Water bath heating Temperature control of the sample was achieved using a water bath. S6: Drug Residue Detection and Microbiological Detection The prepared samples were tested for drug residues; the ATP biofluorescence detector integrated in the box was used to quickly detect the food contact surface. The ATP biofluorescence detector directly read the RLU value and compared it with the preset safety limit to obtain microbial contamination index data. S7: Recording and Transmission After the test is completed, the test results, operating parameters, and timestamp data are exported to an external computer system via the USB interface on the device for recording, analysis, or generating a test report.

[0017] Compared with the prior art, the present invention has at least the following beneficial effects: The food safety pretreatment and testing device of this invention includes a housing, a control module, a pretreatment module, and an ATP biofluorescence detector. The internal space of the housing is precisely planned and laid out in three dimensions. Heating units (concentrator, water bath) are physically isolated from temperature-sensitive units (centrifuge motor, electronic components of the control module) or effectively designed with heat dissipation ducts to prevent mutual interference. High-vibration units (centrifuge, mixer) are designed with shock-absorbing structures (such as rubber pads, independent bases) to prevent their vibration from affecting the stable operation of other modules and the overall user experience. Since multiple motors and electronic systems operate simultaneously in a confined space, careful design of circuit layout, shielding, and grounding is required to prevent mutual electromagnetic interference and ensure stable control system signals and accurate detector data. Users do not need to face... Instead of using different buttons and screens on multiple devices, this system operates all functions through a central control panel, providing users with a unified perspective to manage the entire complex testing process. At any time (e.g., when observing violent solvent boiling during concentration), users can input commands via the button regulator. These commands are sent to the microcomputer control system, which identifies the concentrator as currently in operation and adjusts its parameters (e.g., reducing airflow speed) through corresponding control circuits (such as motor drivers and heater drivers), feeding the new parameters back to the unified digital display in real time. The ATP biofluorescence detector, as a built-in module, is physically and electrically on par with other pretreatment modules and can be used for rapid detection of food contact surfaces. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural diagram of the food safety pretreatment and detection device in an embodiment of the present invention; Figure 2This is a schematic diagram of the concentrator in an embodiment of the present invention; Figure 3 This is a schematic diagram of the centrifuge structure in an embodiment of the present invention; Figure 4 This is a schematic diagram of the mixing device in an embodiment of the present invention; Figure 5 This is a schematic diagram of the water bath in an embodiment of the present invention; Figure 6 This is a schematic flowchart of the food safety pretreatment and detection method in an embodiment of the present invention.

[0019] Explanation of reference numerals in the attached figures: 1-Box; 2-Control module; 21-Digital tube display; 22-Button regulator; 3-Concentrator; 31-Base; 311-First heating hole; 32-Gas box; 321-Gas needle; 33-Electric lifting mechanism; 34-Air pump; 4-Centrifuge; 41-Centrifuge chamber; 42-Brushless DC motor; 421-Output shaft; 43-Rotor; 432-Centrifuge tube position; 44-Speed ​​control module; 45-Timer module; 5-Mixer; 51-Base; 53-Drive motor; 531-Eccentric shaft; 54-Speed ​​control module; 6-Water bath; 61-Boiler body; 611-Water bath chamber; 6111-Centrifuge tube rack; 62-Electric heater; 63-Second temperature sensor; 7-ATP biofluorescence detector. Detailed Implementation

[0020] 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. 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; they can also refer to the internal connection of two components; and they can refer to a wireless connection or a wired connection. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0021] The terms “upper,” “lower,” “left,” “right,” and similar expressions used in this document are for illustrative purposes only and do not represent the only possible implementation.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Please see Figure 1-5 As shown, this embodiment of the invention provides a food safety pretreatment and detection device, which includes a housing 1, a control module 2, a pretreatment module, and an ATP biofluorescence detector 7, wherein: The control module 2 is integrated on the housing 1. The control module 2 includes a microcomputer control system and a visual operation panel, a digital tube display 21 and a button regulator 22 that are electrically connected to the microcomputer control system. The pretreatment module is integrated inside the housing 1. The pretreatment module includes a concentrator 3 for sample purging and concentration, a centrifuge 4 for sample separation, a homogenizer 5 for sample mixing, and a water bath 6 for sample isothermal treatment. The ATP bio-fluorescence detector 7 is integrated inside the housing 1. The ATP bio-fluorescence detector 7 is used to detect microbial contamination on food contact surfaces. The control module 2 is adapted to adjust and control the corresponding operating parameters via the button regulator 22 when any of the units in the concentrator 3, centrifuge 4, mixer 5 or water bath 6 is running, and the parameters are displayed in real time on the visual operation panel.

[0023] For further details, please refer to Figure 1 As shown, in some embodiments of the present invention, the device further includes an intelligent temperature control system integrated into the concentrator 3 and / or the water bath 6. This intelligent temperature control system includes a temperature detector, a heating actuator, a cooling actuator, and a PID temperature controller. The heating actuator and the cooling actuator are electrically connected to the PID temperature controller. The temperature detector is used to collect the actual temperature of at least one functional module in the pretreatment module in real time and output a temperature signal. The PID temperature controller is used to compare the actual temperature with a preset target temperature and output a heating control signal and / or a cooling control signal based on a PID algorithm. The heating actuator is used to receive the heating control signal and perform heating operations on the functional module. The cooling actuator is used to receive the cooling control signal and perform cooling operations on the functional module.

[0024] In this embodiment, through the precise calculation of the PID temperature controller, the system can effectively suppress temperature fluctuations and improve the accuracy and reliability of the test results. The natural cooling method allows users to quickly cool the system to a safe temperature after concentration before proceeding to the next step, or provides the possibility for continuous experimental processes that require different temperature steps, greatly improving the working efficiency of the equipment and the flexibility of the experimental process.

[0025] In some other embodiments, the cooling actuator may also be used when the object being processed is not in use, in which case natural cooling is employed for temperature reduction.

[0026] Specifically, please refer to Figure 2 As shown, the concentrator 3 includes a base 31, an air box 32, an electric lifting mechanism 33, and an air pump 34, wherein: The upper surface of the base 31 is provided with a plurality of first heating holes 311 extending in the vertical direction. The first heating holes 311 are evenly distributed on the same circumference and the hole diameter matches the outer diameter of the centrifuge tube. The gas box 32 is located above the first heating hole 311 and is coaxially arranged with each first heating hole 311. The lower surface of the gas box 32 is provided with gas needles 321 corresponding to each of the multiple first heating holes 311. The gas needles 321 are used to deliver gas into the inner cavity of the centrifuge tube. One end of the electric lifting mechanism 33 is fixed to the base 31, and the other end is connected to the air box 32. The electric lifting mechanism 33 is adapted to drive the air box 32 to make linear motion in the vertical direction in order to adjust the depth of the air needle 321 inserted into the centrifuge tube. The air pump 34 is built into the base 31 and fixed inside. The air outlet of the air pump 34 is connected to the air inlet of the air box 32 through a gas pipeline.

[0027] Specifically, in this embodiment, the base 31 serves as the support platform and heat source carrier of the concentrator 3. It integrates high-precision heating elements (such as heating wires) and temperature sensors (such as PT100). The multiple first heating holes 311 on the upper surface are designed to extend vertically and be evenly distributed on the same circumference. This structural layout ensures that the distance between each first heating hole 311 and the gas needle 321 is consistent, ensuring the uniformity of airflow and heat conduction, thereby realizing the parallel and synchronous processing of multiple samples and improving efficiency (supporting the simultaneous processing of 12 samples).

[0028] The diameter of the first heating hole 311 is matched with the outer diameter of the centrifuge tube. If it is too tight, it will be difficult to put in or take out the centrifuge tube; if it is too loose, it will reduce the heat transfer efficiency. This matching ensures full contact between the centrifuge tube wall and the heating hole wall, achieving efficient and uniform heating, and enabling the sample to be heated quickly and uniformly to the set temperature.

[0029] The gas chamber 32 acts as a gas collecting chamber, evenly distributing the airflow from a single gas source (built-in air pump) to multiple gas needles 321. This design replaces the complex method of connecting individual tubing to each gas needle 321 in traditional devices, simplifying the structure, reducing the risk of leakage, and ensuring the consistency of airflow from each gas needle outlet. The gas needles 321 are coaxially aligned with the first heating hole 311 and correspond one-to-one, ensuring that the airflow can be blown vertically and accurately towards the liquid surface at the bottom of the centrifuge tube. This coaxial design avoids splashing and sample loss caused by airflow hitting the tube wall, while also optimizing the gas-liquid contact area and improving the efficiency of solvent evaporation.

[0030] The electric lifting mechanism 33 replaces the traditional manual knob adjustment method, avoiding the problems of low efficiency, poor consistency, and difficulty in precise control that exist in manual adjustment. Driven by a motor, the electric lifting mechanism 33 achieves one-button lifting and can quickly adapt to centrifuge tubes of different height specifications (such as 5mL tubes).

[0031] For example, the electric lifting mechanism 33 can be adjusted in real time or in stages according to the solvent level. When the liquid level is high in the initial stage of concentration, the gas needle 321 can penetrate closer to the liquid surface to improve purging efficiency; as the liquid level drops, the gas needle 321 can drop accordingly to always maintain the optimal purging distance and prevent sample loss due to excessive airflow when the solvent dries quickly.

[0032] The air pump 34 is built into the base 31, realizing "integrated equipment and device", which completely eliminates the dependence on bulky external gas cylinders and greatly improves the portability and operational flexibility of the equipment.

[0033] After the user places the sample, they set the temperature, airflow speed, and lifting parameters on the control panel. Upon startup, the heating base 31 begins to heat up, the air pump 34 starts supplying air, and the electric lifting mechanism 33 lowers the air chamber 32 to a suitable height according to a preset program or user command. The airflow enters the air chamber 32 from the air pump 34 through the pipeline, is evenly distributed, and then flows out from each air needle 321, blowing vertically towards the liquid surface of the centrifuge tube. At the same time, heat is efficiently conducted to the sample through the tube wall of the first heating hole 311. The entire process is carried out under the monitoring of the microcomputer control system, realizing unattended automated concentration.

[0034] For more details, please refer to Figure 2 As shown, the temperature detector is a first temperature sensor located near the first heating hole 311. The first temperature sensor is used to detect the temperature of the first heating hole 311 in real time and output a temperature signal. The heating actuator is an electric heating wire embedded in the base 31 and arranged around each of the first heating holes 311, used to adjust the temperature of each of the first heating holes 311.

[0035] In this specific embodiment, the user sets a target temperature (e.g., 60.0℃) on the control panel. The first temperature sensor measures the actual temperature of the first heating hole 311 in real time (e.g., 59.5℃) and transmits this signal to the microcomputer control system. The microcomputer control system compares the measured value (59.5℃) with the target value (60.0℃), calculates the deviation (-0.5℃), and calculates the required heating power based on the deviation using intelligent algorithms such as PID (proportional-integral-derivative). It then outputs a control signal (e.g., a PWM wave) to adjust the current supplied to the heating wire. As the heating wire power increases, the temperature begins to rise. When the temperature exceeds the target value, the microcomputer control system reduces the power. After several rapid adjustments, the system reaches a dynamic equilibrium state, stably controlling the temperature within a very small fluctuation range (±0.3℃) near the target value. This entire process continuously cycles, forming a closed loop to continuously counteract temperature disturbances caused by environmental heat dissipation and sample addition.

[0036] Specifically, please refer to Figure 1 , 5 As shown, the water bath 6 includes a pot body 61 with an opening at the top to form a constant temperature water bath chamber 611. The water bath chamber 611 is provided with a plurality of vertically downward centrifuge tube racks 6111, and the centrifuge tube racks 6111 are used to place and position centrifuge tubes. The heating actuator is an electric heater 62 fixed to the lower part of the pot body 61 and surrounding the water bath chamber 611. The electric heater 62 is used to heat the liquid in the water bath chamber 611 to a set temperature. The temperature detector is a second temperature sensor 63 inserted into the water bath chamber 611 and arranged adjacent to the centrifuge tube rack 6111. The second temperature sensor 63 is used to detect the liquid temperature in real time and output a temperature signal.

[0037] In this embodiment, after the user sets the target temperature, the PID temperature controller starts, and the electric heater 62 begins to heat the pot body 61 in a circular motion. The heat is rapidly and evenly distributed through the metal pot body and its complex internal "water passages (heat dissipation holes)". The second temperature sensor 63 monitors the actual temperature of the heating block in real time and feeds it back to the PID controller. The controller dynamically adjusts the power of the electric heater 62 through an algorithm, ultimately maintaining the temperature of the entire metal heating block (including the inner wall of each heating hole) precisely and stably at the set value. When a low-temperature centrifuge tube is placed inside, its strong heat capacity and rapid heat replenishment capability allow its temperature to recover quickly.

[0038] More specifically, the device also includes a fault self-diagnosis system electrically connected to the microcomputer control system. The fault self-diagnosis system is used to monitor the operating status of the centrifuge 4 in real time, and to perform automatic deceleration and shutdown and alarm operations when overspeed, speed loss or imbalance faults are detected.

[0039] In this embodiment, a series of sensors tightly coupled to the centrifuge spindle or drive motor acquire physical signals in real time. For example, high-precision encoders or Hall effect sensors are used to convert the mechanical rotational position / velocity of the motor rotor into digital or pulse signals for the microcomputer control system to calculate the real-time rotational speed (RPM). A microelectromechanical system (MEMS) vibration accelerometer, installed in the centrifuge chamber or motor base, is used to monitor mechanical vibrations of specific frequencies and amplitudes caused by mass imbalance. Current sensors (such as Hall current sensors) monitor the current value of the motor drive circuit; speed loss (such as jamming) or severe imbalance will cause sudden changes in motor load, resulting in abnormal current waveforms. The microcomputer control system performs real-time filtering, amplification, and analog-to-digital conversion on the acquired multi-channel sensor signals.

[0040] For example, the system compares the calculated real-time rotational speed with the user-defined safe rotational speed limit (or the system's preset mechanical speed limit). If the real-time rotational speed exceeds the safe threshold, an overspeed fault is instantly identified. The system continuously compares the "command speed" with the "feedback speed." If the feedback speed is detected to be less than the command speed and the motor current is greater than the no-load current for a certain period of time, a speed loss (stalled or overload) fault is identified. The system performs Fast Fourier Transform (FFT) spectrum analysis on the vibration sensor signal to extract the amplitude of the vibration component with the same frequency as the rotor rotation. If this amplitude exceeds the safety threshold dynamically calculated based on the rotor model and current rotational speed, an imbalance fault is identified.

[0041] Specifically, please refer to Figure 3 As shown, the centrifuge 4 includes a centrifuge chamber 41, a brushless DC motor 42, a rotor 43, and a speed control module 44, wherein: The centrifuge chamber 41 is a chamber that is directly machined or formed on the housing 1. This integrated structure maximizes space saving and avoids the bulky problem caused by external centrifuges. The centrifuge chamber 41 is equipped with a centrifuge cover, preferably made of rubber.

[0042] The brushless DC motor 42 is fixed to the bottom of the centrifuge chamber 41, and the output shaft 421 of the brushless DC motor 42 extends vertically upward into the centrifuge chamber 411. Compared with the traditional brushed motor, the brushless DC motor 42 replaces the physical brushes and commutator with an electronic commutator (driven by the speed control module). Its output shaft 421 is installed vertically upward, and the rotor 43 is directly installed on the output shaft of the brushless DC motor 42 through a quick-release mechanism (such as a knob buckle).

[0043] The rotor 43 is detachably mounted on the output shaft 421. The rotor 43 has multiple evenly distributed centrifuge tube positions 432. The axis of each centrifuge tube position 432 forms a fixed angle with the axis of the output shaft 421, which is used to accommodate multiple centrifuge tubes at the same time. When the brushless DC motor 42 rotates, the centrifugal force on the sample can be decomposed into two components, vertical and horizontal, which causes the sample to aggregate (precipitate) at the bottom of the tube or to stratify according to density.

[0044] The speed control module 44 is electrically connected to the brushless DC motor 42 and is used to steplessly adjust and stabilize the speed of the output shaft 421. The speed control module 44 receives instructions from the microcomputer control system and, through pulse width modulation (PWM) technology, precisely controls the magnitude and timing of the current supplied to each phase winding of the brushless DC motor 42, thereby achieving stepless adjustment of the motor speed. The closed-loop control algorithm inside the module continuously compares the target speed with the actual speed fed back by the encoder and dynamically adjusts the PWM output to stabilize the speed and resist interference caused by voltage fluctuations or load changes.

[0045] The timing module 45 is electrically connected to the speed control module 44. The timing module 45 is used to send a stop signal to stop the brushless DC motor 42 from rotating. When the user sets a time, the timing module 45 starts counting down. When the countdown ends, the timing module 45 sends a stop signal to the speed control module 44, and the speed control module 44 then starts a controlled deceleration program (instead of a sudden power cut-off) to bring the motor to a smooth stop.

[0046] Specifically, please refer to Figure 1 , 4 As shown, the mixer 5 includes a base 51, a drive motor 53, and a speed control module 54, wherein: The base 51 is the structural foundation of the entire mixer 5, and its interior is used to house the drive motor 53. The upper surface of the base 51 is provided with an installation interface 511. The drive motor 53 is fixed inside the base 51. The output end of the drive motor 53 is connected to the eccentric shaft 531. The eccentric shaft 531 is used to generate track oscillation with a rotation diameter of 4 mm. The top end of the eccentric shaft 531 is rigidly connected to the bottom of the cavity of the mounting interface 511 so as to directly transmit the oscillation power to the mounting interface 511.

[0047] When the drive motor 53 rotates, the center of mass of the eccentric shaft 531 is not at the center of rotation, which generates a periodic centrifugal force. This force is transmitted to the mounting interface 511 through the base 51, forcing the sample tube on the mounting interface 511 to oscillate in an orbital manner. At the same time, to prevent the test tube from falling off, the test tube is manually assisted in mixing.

[0048] The speed control module 54 is electrically connected to the drive motor 53. The speed control module 54 is used to steplessly adjust and maintain the set speed of the drive motor 53. The speed control module 54 receives instructions from the microcomputer control system. It uses pulse width modulation (PWM) technology to steplessly adjust the voltage or current supplied to the drive motor 53, thereby achieving continuous and precise control of the drive motor 53's speed. The speed control module 54 also has an internal closed-loop feedback mechanism (possibly by detecting the motor's back electromotive force) to maintain the stability of the set speed and resist speed fluctuations caused by different loads (clamping tubes of different weights).

[0049] Therefore, through intense three-dimensional vortexing, trace to large volumes (1.5-50 ml) of sample can be thoroughly mixed within seconds to tens of seconds, far exceeding the efficiency of manual oscillation or simple vibratory mixers. This is crucial for rapid extraction and reaction termination, directly improving overall detection efficiency.

[0050] Specifically, in some embodiments of the present invention, the ATP biofluorescence detector 7 includes a housing, a photoelectric sensing module, a biofluorescence reagent holder, a microcontroller, a memory, and a USB interface, wherein: The housing contains a dark chamber with an openable and closable light-shielding cover at the top, forming an insertion hole adapted to the outer diameter of a standard test tube. A photoelectric sensing module is installed at the bottom of the dark chamber, comprising a photon-counting photomultiplier tube and a coupled sampling chamber. This module detects the fluorescence signal emitted by the reaction per unit time and outputs an RLU value proportional to the ATP content. A biofluorescent reagent card is located on the upper surface of the housing, used to fix a disposable reagent card pre-loaded with luciferase / luciferin reagent, allowing the reagent and sample to mix instantaneously within the sampling chamber. A microcontroller is electrically connected to the photoelectric sensing module, displaying the RLU value on a visual operation panel and simultaneously executing an E. coli screening algorithm, outputting a positive alert when the RLU value exceeds a preset threshold. A memory is connected to the microcontroller bus to save test result records. A USB interface is located on the side wall of the housing and electrically connected to the microcontroller, used to export the test result records from the memory to an external computer.

[0051] Specifically, in this embodiment, the dark chamber inside the housing is the foundation of the entire optical detection process. Its closable top cover, when closed, forms a physical barrier with the housing, ensuring a near-absolutely dark environment inside. The inserted test tube is precisely positioned through a standard outer diameter fitting socket, while simultaneously ensuring light-shielding and sealing. Because photon counting detection is extremely sensitive to stray light, even the slightest ambient light leakage can generate extremely high background noise, drowning out the weak bioluminescent signal and leading to detection failure or a sharp drop in accuracy. This dark chamber structure physically eliminates this, achieving an extremely low background of ≤2 RLU and 2×10⁻⁶ RLU.18 The absolute prerequisite for ultra-high detection sensitivity of mol ATP.

[0052] A photon-counting photomultiplier tube (PMT) is a vacuum tube that uses the photoelectric effect and secondary electron emission effect to exponentially amplify weak light signals and convert them into electrical signals. "Photon-counting" means that it operates in a mode that counts individual photons, making it one of the most sensitive photodetectors currently available.

[0053] The coupled sampling cavity ensures that the lower part of the test tube (the reaction area) is in the optimal optical coupling position with the photocathode surface of the photon counting photomultiplier tube, maximizing the collection of every photon emitted by the reaction and reducing optical path loss.

[0054] The luciferase / luciferin reagent is pre-loaded into disposable reagent cards. Users simply add the prepared sample solution to the reagent card and insert it into the designated slot on the detector. When the reaction cell at the end of the reagent card is inserted into the darkroom socket, the mechanical mechanism causes the sample and reagent to mix instantaneously.

[0055] The microcontroller receives the electrical pulse signal (RLU) output by the PMT. It also incorporates a built-in E. coli screening algorithm, which uses an empirical model based on extensive experimental data to compare the detected ATP concentration or RLU value with a preset threshold. When the threshold is exceeded, the microcontroller not only displays the numerical value but also directly outputs a clear "positive" or "exceeds the limit" message.

[0056] Specifically, in this embodiment, when the RLU value exceeds a preset threshold, the value is displayed in red to represent a positive result; when the RLU value does not exceed the preset threshold, the value is displayed in green to represent a negative result. The memory automatically saves complete data for each test, including RLU value, timestamp, and other information. Storing more than 2,000 records meets the needs of large-scale on-site screening and achieves complete traceability of the testing process. The USB interface provides a bridge to connect with PC-based data management software, allowing users to export data in batches, perform in-depth statistical analysis, generate test reports, or report to the regulatory system, completing a closed-loop data flow from "rapid on-site screening" to "laboratory quality management."

[0057] Please see Figure 6 As shown, other embodiments of the present invention also provide a food safety pretreatment and detection method based on the above-described apparatus, the detection method comprising the following steps: S1: Sample Preparation The food samples to be tested were preliminarily processed and packaged; Although manual intervention is still required in this step, it has been greatly simplified. Users only need to perform the most basic operations (such as weighing, homogenizing, and diluting) and dispense the samples into standardized centrifuge tubes.

[0058] The purpose of this step is to transform non-standardized raw food samples into standardized samples suitable for subsequent automated module processing, providing a unified input interface for the entire automated process.

[0059] S2: Concentration Process The control module 2 sets and adjusts the concentration temperature, airflow speed and concentration time in real time according to the solvent properties and volume. It uses the air pump 34 and electric heating wire built into the concentrator 3 to purge and concentrate the sample, and optimizes the concentration process through the electric lifting mechanism 33. In this step, the user places the sample tube into the concentrator 3. The control module 2 allows the user to set parameters according to the solvent properties (such as boiling point) and volume. More importantly, the system has real-time adjustment capabilities (such as automatically lowering the needle height in the later stages of concentration to prevent splashing); the built-in air pump and electric heating wire provide power and heat source, while the electric lifting mechanism 33 performs precise height adjustment.

[0060] Thus, this step achieves selective evaporation of volatile solvents and enrichment of target analytes. The setting and adjustment of intelligent parameters replaces the experience-based judgment required in traditional methods, ensuring both high efficiency in the concentration process and sample safety (avoiding overheating or cross-contamination).

[0061] S3: Centrifugal stratification Set the target relative centrifugal force value, automatically calculate and execute the corresponding rotation speed, and use centrifuge 4 to centrifuge the sample for separation. In this step, the user does not need to calculate the rotational speed. The system's algorithm automatically calculates the required rotational speed (RPM) based on the current rotor radius and executes it precisely. This design delegates complex physical calculations to the machine, eliminating human error and ensuring that different batches and different operators can obtain completely consistent separation results, greatly improving the comparability and reliability of the data.

[0062] S4: Oscillate and mix In this step, the sample is vortexed and mixed using a mixer 5; the sample tube is placed on the mounting interface 511 of the base 51, and the speed and time are set before starting. The device generates orbital oscillation, causing the sample to form a violent vortex inside the tube.

[0063] This step aims to resuspend the sample, mix the extract, or homogenize the reaction system. Its standardized operation ensures thorough and consistent mixing, laying the foundation for accurate subsequent detection.

[0064] S5: Water bath heating The temperature of the sample was controlled using a water bath 6. In this step, the sample tubes are placed in the centrifuge rack of the water bath 6, and the precise target temperature and time are set for temperature regulation. This step is used to stimulate or accelerate specific biochemical reactions, such as enzymatic digestion, derivatization, or cell lysis. High-precision temperature control (±0.3℃) ensures that these heat-sensitive reactions can be carried out under optimal and reproducible conditions.

[0065] S6: Drug Residue Detection and Microbiological Detection The prepared samples were tested for drug residues; at the same time, the ATP bio-fluorescence detector 7 integrated in the box 1 was used to quickly detect the food contact surface. The ATP bio-fluorescence detector 7 directly read the RLU value and compared it with the preset safety limit to obtain microbial contamination index data. In this step, the food contact surface is wiped with the reagent card of the ATP detector 7, reacted with the reaction solution, and then inserted into the dark chamber. The photomultiplier tube (PMT) detects the light emission value (RLU). The microcontroller not only displays the RLU value, but also compares it with the preset safety limit to make a judgment.

[0066] S7: Recording and Transmission After the test is completed, the test results, operating parameters, and timestamp data are exported to an external computer system via the USB interface 23 on the device for recording, analysis, or generating a test report.

[0067] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of this disclosure, and all such changes and modifications will fall within the scope of protection of this invention.

Claims

1. A food safety pre-treatment and detection device, characterized in that, include: Box (1); The control module (2) is integrated on the housing (1). The control module (2) includes a microcomputer control system and a visual operation panel, a digital tube display (21) and a button regulator (22) that are electrically connected to the microcomputer control system. A pretreatment module, integrated inside the housing (1), includes a concentrator (3) for sample purge and concentration, a centrifuge (4) for sample separation, a homogenizer (5) for sample mixing, and a water bath (6) for sample constant temperature incubation; and An ATP biofluorescence detector (7) is integrated inside the housing (1). The ATP biofluorescence detector (7) is used to detect microbial contamination on food contact surfaces. The control module (2) is adapted to adjust and control the corresponding operating parameters through the button regulator (22) when any of the concentrator (3), centrifuge (4), mixer (5) or water bath (6) is running, and the parameters are displayed in real time on the visual operation panel.

2. The food safety pre-treatment and detection device of claim 1, wherein, It also includes an intelligent temperature control system integrated into the concentrator (3) and / or the water bath (6). The intelligent temperature control system includes a temperature detector, a heating actuator, a cooling actuator, and a PID temperature controller. The heating actuator and the cooling actuator are electrically connected to the PID temperature controller. The temperature detector is used to collect the actual temperature of at least one functional module in the pretreatment module in real time and output a temperature signal. The PID temperature controller is used to compare the actual temperature with a preset target temperature and output a heating control signal and / or a cooling control signal based on a PID algorithm. The heating actuator is used to receive the heating control signal and perform a heating operation on the functional module. The cooling actuator is used to receive the cooling control signal and perform a cooling operation on the functional module.

3. The food safety pretreatment and testing device according to claim 2, characterized in that, The concentrator (3) includes: The base (31) has a plurality of first heating holes (311) extending in a vertical direction on its upper surface. The first heating holes (311) are evenly distributed on the same circumference and the hole diameter matches the outer diameter of the centrifuge tube. The gas box (32) is located above the first heating hole (311) and is coaxially arranged with each of the first heating holes (311). The lower surface of the gas box (32) is provided with gas needles (321) corresponding to each of the multiple first heating holes (311). The gas needles (321) are used to deliver gas into the inner cavity of the centrifuge tube. An electric lifting mechanism (33) is fixed at one end to the base (31) and connected at the other end to the air box (32). The electric lifting mechanism (33) is adapted to drive the air box (32) to make linear motion in the vertical direction in order to adjust the depth of the air needle (321) inserted into the centrifuge tube. An air pump (34) is built into the base (31), and the air outlet of the air pump (34) is connected to the air inlet of the air box (32) through a gas pipeline (37).

4. The food safety pretreatment and testing device according to claim 3, characterized in that, The temperature detector is a first temperature sensor located near the first heating hole (311). The first temperature sensor is used to detect the temperature of the first heating hole (311) in real time and output a temperature signal. The heating actuator is an electric heating wire embedded in the base (31) and arranged around each of the first heating holes (311), used to adjust the temperature of each of the first heating holes (311).

5. The food safety pretreatment and testing device according to claim 2, characterized in that, The water bath (6) includes a pot body (61) with an opening at the top to form a constant temperature water bath chamber (611). The water bath chamber (611) is provided with a plurality of vertically downward centrifuge tube racks (6111), and the centrifuge tube racks (6111) are suitable for placing positioning centrifuge tubes. The heating actuator is an electric heater (62) fixed to the lower part of the pot body (61) and arranged around the water bath cavity (611). The electric heater (62) is used to heat the liquid in the water bath cavity (611) to a set temperature. The temperature detector is a second temperature sensor inserted into the water bath (611) and arranged adjacent to the centrifuge tube rack (6111). The second temperature sensor is used to detect the liquid temperature in real time and output a temperature signal.

6. The food safety pretreatment and testing device according to claim 1, characterized in that, It also includes a fault self-diagnosis system electrically connected to the microcomputer control system. The fault self-diagnosis system is used to monitor the operating status of the centrifuge (4) in real time, and to perform automatic deceleration and alarm operations when overspeed, speed loss or imbalance faults are detected.

7. The food safety pretreatment and testing device according to claim 1, characterized in that, The centrifuge (4) includes: Centrifuge chamber (41) is formed on the box body (1) and is provided with an openable and closable centrifuge cover; A brushless DC motor (42) is fixed at the bottom of the centrifuge chamber (41), and the output shaft (421) of the brushless DC motor (42) extends vertically upward into the centrifuge chamber (41). The rotor (43) is detachably mounted on the output shaft (421). The rotor (43) is provided with a plurality of evenly distributed centrifuge tube positions (432). The axis of each centrifuge tube position (432) forms a fixed angle with the axis of the output shaft (421) to accommodate multiple centrifuge tubes at the same time. The speed control module (44) is electrically connected to the brushless DC motor (42) and is used to steplessly adjust and stabilize the speed of the output shaft (421); The timing module (45) is electrically connected to the speed control module (44). The timing module (45) is used to send a stop signal to stop the brushless DC motor (42) from rotating.

8. The food safety pretreatment and testing device according to claim 1, characterized in that, The mixer (5) includes: The base (51) has an installation interface (511) on its upper surface. A drive motor (53) is fixed inside the base (51). The output end of the drive motor (53) is connected to an eccentric shaft (531). The eccentric shaft (531) is used to generate track oscillation with a rotation diameter of 4 mm. The top end of the eccentric shaft (531) is rigidly connected to the bottom of the cavity of the mounting interface (511) so as to directly transmit the oscillation power to the mounting interface (511). The speed control module (54) is electrically connected to the drive motor (53) and is used to steplessly adjust and maintain the speed of the drive motor (53).

9. The food safety pretreatment and testing device according to claim 1, characterized in that, The ATP bioluminescence detector (7) includes: The housing has a dark chamber inside, and the top of the dark chamber has an openable and closable light-shielding cover and forms an insertion hole that is adapted to the outer diameter of a standard test tube. A photoelectric sensing module is installed at the bottom of the dark chamber. The photoelectric sensing module includes a photon counting photomultiplier tube and a sampling cavity coupled thereto. It is used to detect the fluorescence signal emitted by the reaction per unit time and output an RLU value proportional to the ATP content. A biofluorescent reagent holder is located on the upper surface of the housing to fix a disposable reagent card pre-loaded with luciferase / luciferin reagent, allowing the reagent and sample to mix instantaneously in the sampling chamber; A microcontroller is electrically connected to the photoelectric sensing module. The microcontroller is used to display the RLU value on the visual operation panel and execute the coliform bacteria screening algorithm. When the RLU value exceeds a preset threshold, a positive prompt is output. A memory, connected to the microcontroller bus, is used to store the detection result records; A USB interface is located on the side wall of the housing and electrically connected to the microcontroller, used to export the detection results recorded in the memory to an external computer.

10. A food safety pretreatment and detection method based on the apparatus according to any one of claims 1-9, characterized in that, Includes the following steps: S1: Sample Preparation The food samples to be tested were preliminarily processed and packaged; S2: Concentration Process The control module (2) sets and adjusts the concentration temperature, airflow speed and concentration time in real time according to the solvent properties and volume. It uses the air pump (34) and electric heating wire built into the concentrator (3) to purge and concentrate the sample, and optimizes the concentration process through the electric lifting mechanism (33). S3: Centrifugal stratification Set the target relative centrifugal force value, automatically calculate and execute the corresponding rotation speed, and use a centrifuge (4) to centrifuge and separate the sample; S4: Oscillate and mix The sample was mixed by vortexing using a mixer (5); S5: Water bath heating The temperature of the sample was controlled using a water bath (6); S6: Drug residue detection and microbial detection; The prepared samples were tested for drug residues; the ATP biofluorescence detector (7) integrated in the box (1) was used to quickly detect the food contact surface. The ATP biofluorescence detector (7) directly read the RLU value and compared it with the preset safety limit to obtain microbial contamination index data. S7: Recording and Transmission After the test is completed, the test results, operating parameters, and timestamp data are exported to an external computer system via the USB interface (23) on the device for recording, analysis, or generating a test report.

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