Food freshness detection device and detection method

Abstract

The food freshness detection device specifically comprises a main body, and a sampling assembly, a detection assembly and an air exhaust assembly which are sequentially arranged on the main body, the sampling assembly comprises a shell, a temperature adjusting part and a triggering part, the shell is arranged on the main body, and a sampling cavity is concavely formed in the end, close to food, of the shell; the temperature adjusting part is arranged on the sampling cavity; the detection assembly comprises a detection cavity and a detector, the detection cavity is communicated with the sampling cavity, a gas outlet is formed in the side, away from the sampling cavity, of the detection cavity, and the gas extraction assembly is used for sucking gas in the sampling cavity into the detection cavity and discharging the gas from the gas outlet; the detector is arranged in the detection cavity and is used for detecting the concentration of ammonia gas in the detection cavity. By adjusting the food temperature, triggering air exhaust detection at a proper temperature and timely discharging residual gas, the interference of low temperature and gas residue on ammonia gas detection is effectively avoided, and the accuracy, stability and reliability of food freshness detection are improved.

Description

Technical Field

[0001] This invention relates to the field of detection device technology, specifically to a food freshness detection device and detection method. Background Technology

[0002] Food freshness is a crucial indicator of food safety and quality, directly impacting consumer health and safety. Especially during the production, transportation, storage, and sale of high-protein foods such as meat and seafood, spoilage can lead not only to economic losses but also potentially food safety incidents. Therefore, achieving rapid, accurate, and convenient detection of food freshness has become a critical technological requirement in the food distribution and regulatory sectors.

[0003] Among existing detection technologies, a common approach is to determine the freshness of food by detecting changes in the concentration of volatile ammonia or amine gases produced during food spoilage. This method is based on the principle that food proteins decompose to produce nitrogen-containing volatile substances. The detection principle is clear, and the cost is relatively low, thus it has gained some traction in practical applications.

[0004] However, ammonia concentration-based detection devices still have certain limitations. For chilled foods, the low-temperature storage or cold chain transportation environment inhibits the production and release of ammonia, resulting in a significantly lower evaporation rate compared to foods at room temperature. Even if the food has deteriorated to some extent, the concentration of ammonia released in a short period remains low, easily leading to underestimation of the actual freshness of the food and making it difficult to accurately reflect its actual freshness. Furthermore, existing detection devices may retain the odor of previously tested food during use, affecting subsequent test results and impacting the accuracy and reliability of the detection.

[0005] Therefore, providing an accurate and reliable food freshness detection device and method has become an urgent technical problem to be solved in this field. Summary of the Invention

[0006] The purpose of this invention is to provide a food freshness detection device and method to solve the technical problem that existing food freshness detection devices are easily affected by low temperature inhibiting ammonia volatilization and residual odors in the detection of chilled food, thus limiting the accuracy of food freshness detection.

[0007] To achieve this objective, the present invention adopts the following technical solution: A food freshness detection device includes a main body, and a sampling component, a detection component, and a vacuum component sequentially disposed on the main body. The sampling component includes a housing, a temperature regulating component, and a trigger component. The housing is disposed on the main body, and a sampling chamber is recessed at the end of the housing near the food. The temperature regulating component is disposed on the sampling chamber and used to regulate the food temperature in the area enclosed by the sampling chamber. The trigger component is used to detect the food temperature in the area enclosed by the sampling chamber. The detection component includes a detection chamber and a detector. The detection chamber is connected to the sampling chamber, and an air outlet is disposed on the side of the detection chamber away from the sampling chamber. The vacuum component is used to draw gas from the sampling chamber into the detection chamber and discharge the gas from the air outlet. The detector is disposed in the detection chamber and used to detect the ammonia concentration in the detection chamber. The vacuum component is electrically connected to the trigger component, and the vacuum component is activated when the food temperature reaches a preset value.

[0008] Optionally, the food freshness detection device further includes a cleaning component, which includes a sliding plate and a driving component. The sliding plate is slidably installed in the detection chamber along a first direction via the driving component, wherein the first direction is the flow direction of gas in the detection chamber. The sliding plate is provided with a through hole, and the temperature regulating component is provided on the side of the sliding plate close to the food. The temperature regulating component and the through hole are spaced apart in the vertical direction.

[0009] Optionally, the driving component includes a first magnetic plate and a second magnetic plate. The first magnetic plate is disposed between the sampling chamber and the detection chamber. The first magnetic plate has a first through groove recessed therein, which is directly opposite to the through hole. The second magnetic plate is disposed at the end of the detection chamber away from the first magnetic plate. The second magnetic plate has a second through groove recessed therein, which is directly opposite to the air outlet. Both the first magnetic plate and the second magnetic plate are configured as electromagnets, and their end faces that are close to each other have the same magnetic poles. The sliding plate is configured as a magnetic structure.

[0010] Optionally, the cleaning assembly further includes an adsorption element disposed on the slide plate for adsorbing residual gas in the sampling chamber and the detection chamber.

[0011] Optionally, the slide plate is provided with a protrusion, the protrusion is directly opposite to the temperature regulating component, the protrusion is provided with a groove in the vertical direction, the adsorption component includes a guide plate and an adsorption medium, the guide plate is slidably installed in the groove, the guide plate is provided with a receiving cavity, the receiving cavity is directly opposite to the protrusion, and the adsorption medium is disposed in the receiving cavity.

[0012] Optionally, the guide plate is inverted L-shape, the guide plate includes a vertical plate and a horizontal plate, the receiving cavity is disposed on the vertical plate, the horizontal plate is fixed to the end of the vertical plate, a third magnetic plate is disposed on the detection cavity, the side of the horizontal plate near the third magnetic plate is configured with a magnetic structure, the third magnetic plate is disposed opposite to the horizontal plate and the magnetic poles are opposite.

[0013] Optionally, the trigger includes an expansion body, a first conductor, and a second conductor. The housing has a recessed groove on the side near the food. The second conductor is disposed on the bottom surface of the groove. The expansion body is disposed at the end of the groove near the food. The first conductor is disposed at the end of the expansion body near the second conductor. When the expansion body detects that the food temperature has reached a preset value, the first conductor and the second conductor are electrically connected.

[0014] Optionally, the detection cavity is provided with a slide rail along the first direction, and sliders are provided on both sides of the slide plate. A rolling element is slidably installed in the slide rail, and the slider is slidably installed in the slide rail, with the rolling element abutting against the slider.

[0015] Optionally, a third conductor is provided at one end of the detection cavity near the second magnetic plate, and a fourth conductor is provided on the sliding plate. When the sliding plate slides to fit against the second magnetic plate, the third conductor and the fourth conductor are electrically connected.

[0016] A detection method for a food freshness detection device as described in any of the above claims, comprising the following steps in sequence: Step S1: Arrange the sampling component close to the food to be tested, so that the sampling chamber surrounds at least a portion of the food to be tested; Step S2: The triggering element detects the food temperature in the area enclosed by the sampling chamber in real time. When the food temperature reaches the preset detection temperature, a start signal is generated. When the food temperature does not reach the preset detection temperature, the temperature regulating element is controlled to regulate the temperature of the food in the area enclosed by the sampling chamber until the food temperature reaches the preset detection temperature and a start signal is generated. Step S3: According to the start signal, control the gas extraction component to start, and draw the gas related to food volatiles in the sampling chamber into the detection chamber; Step S4: During the process of gas entering the detection chamber, the detector detects the ammonia concentration in the detection chamber and outputs the corresponding detection data; Step S5: After the test is completed, the tested gas is discharged through the gas outlet, and the freshness of the food is judged based on the test data.

[0017] Compared with the prior art, the present invention has the following beneficial effects: This invention utilizes a collaborative mechanism between a trigger and a temperature regulator in the sampling assembly to monitor and actively regulate the food temperature within the sampling chamber's enclosed area in real time. When the food temperature is below the preset detection temperature, the temperature regulator heats the food until the detection conditions are met before sampling. This reduces the inhibitory effect of low temperatures on ammonia production and volatilization, resulting in more complete and stable ammonia release and improved accuracy. Simultaneously, electrically connecting the trigger to the extraction assembly and using the food temperature reaching a preset value as the activation condition for the extraction assembly avoids premature extraction when the food temperature is insufficient, preventing detection deviations and enhancing the specificity and consistency of the detection process. Furthermore, after detection, the gas in the sampling and detection chambers is promptly discharged through the outlet, effectively reducing interference from residual gas in subsequent detections and improving the reliability and stability of the device during continuous use. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0020] Figure 1 This is a schematic diagram of the overall structure of the food freshness detection device provided in an embodiment of the present invention; Figure 2 for Figure 1 Enlarged view of point A in the middle; Figure 3 This is a cross-sectional view of the food freshness detection device provided in an embodiment of the present invention. Figure 4 for Figure 3 Enlarged view of point B in the middle; Figure 5 for Figure 3 Enlarged view of point C in the middle; Figure 6 for Figure 3 Enlarged view at point D; Figure 7This is a cross-sectional view of another state of the food freshness detection device provided in an embodiment of the present invention; Figure 8 for Figure 7 Enlarged view of point E in the middle.

[0021] Illustrations: 10. Main body; 20. Sampling component; 201. Housing; 2011. Sampling chamber; 2012. Groove; 202. Temperature regulating component; 203. Trigger; 2031. Expansion body; 2032. First conductor; 2033. Second conductor; 30. Detection component; 301. Detection chamber; 3011. Air outlet; 3012. Third magnetic plate; 3013. Slide rail; 3014. Rolling component; 3015. Third conductor; 302. Detector; 40 50. Air extraction assembly; 50. Cleaning assembly; 501. Slide plate; 5011. Through hole; 5012. Protrusion; 5013. Slide groove; 5014. Slider; 5015. Fourth conductor; 502. Driving component; 5021. First magnetic plate; 5022. Second magnetic plate; 5023. First through groove; 5024. Second through groove; 503. Adsorption component; 5031. Guide plate; 5032. Adsorption medium; 5033. Receiving cavity; 311. Vertical plate; 312. Horizontal plate. Detailed Implementation

[0022] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0023] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and 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, and therefore should not be construed as a limitation of the invention. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the connection.

[0024] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0025] Figure 1 This is a schematic diagram of the overall structure of the food freshness detection device provided in an embodiment of the present invention; Figure 2 for Figure 1 Enlarged view of point A in the middle; Figure 3 This is a cross-sectional view of the food freshness detection device provided in an embodiment of the present invention. Figure 4 for Figure 3 Enlarged view of point B in the middle; Figure 5 for Figure 3 Enlarged view of point C in the middle; Figure 6 for Figure 3 Enlarged view at point D; Figure 7 This is a cross-sectional view of another state of the food freshness detection device provided in an embodiment of the present invention; Figure 8 for Figure 7 Enlarged view of point E in the middle.

[0026] The food freshness detection device provided in this embodiment is applicable to scenarios such as cold chain transportation, supermarket retail, catering processing, and food storage. In this embodiment, by improving the structure of the food freshness detection device, ammonia is fully released and accurately sampled under suitable conditions, thereby improving the accuracy, stability, and reliability of continuous use of food freshness detection.

[0027] Please see Figures 1-8 The food freshness detection device provided in this embodiment includes a main body 10, and a sampling component 20, a detection component 30, and a vacuum component 40 sequentially disposed on the main body 10. The sampling component 20 includes a housing 201, a temperature regulating component 202, and a trigger component 203. The housing 201 is disposed on the main body 10, and a sampling chamber 2011 is recessed at the end of the housing 201 near the food. The temperature regulating component 202 is disposed on the sampling chamber 2011 and is used to adjust the food temperature in the area enclosed by the sampling chamber 2011. The trigger component 203 is used to detect the temperature of the food in the area enclosed by the sampling chamber 2011. The detection component 30 includes a detection chamber 301 and a detector 302. The detection chamber 301 is connected to the sampling chamber 2011. An outlet 3011 is provided on the side of the detection chamber 301 away from the sampling chamber 2011. The suction component 40 is used to draw the gas in the sampling chamber 2011 into the detection chamber 301 and discharge the gas from the outlet 3011. The detector 302 is located in the detection chamber 301 and is used to detect the ammonia concentration in the detection chamber 301. The suction component 40 is electrically connected to the trigger 203. When the food temperature reaches the preset value, the suction component 40 is activated.

[0028] Specifically, the main body 10 can be a handheld housing 201 structure, used to integrate and support the sampling component 20, the detection component 30, and the vacuum component 40, facilitating movement and operation in food testing scenarios. The main body 10 can house a power module and control circuitry to provide power to the various functional components and to enable signal transmission and logic control. These structural forms are well-known to those skilled in the art and will not be described in detail here. The housing 201 can be made of plastic or composite materials, with a sampling cavity 2011 recessed at the end closest to the food, used to enclose at least a portion of the food during testing. The temperature regulating component 202 can be an electric heating element, a semiconductor cooling / heating module, or a flexible heating film, etc., all of which are conventional techniques in the field. Through the action of the temperature regulating component 202, food can be heated or kept at a constant temperature in a low-temperature environment, reducing the inhibitory effect of low temperature on the generation and volatilization of ammonia in the food, making the volatilized gases more fully stable, and structurally ensuring improved detection accuracy.

[0029] Because low temperatures significantly inhibit protein decomposition and microbial metabolic activities in food, thereby reducing the generation rate and release intensity of volatile alkaline gases such as ammonia, even if food has already deteriorated to a certain extent, the ammonia concentration on its surface and in the surrounding space may remain at a low level for a short period, which can easily lead to low test results or misjudgments. The temperature regulating element 202, by moderately heating or maintaining a constant temperature for the food within the area enclosed by the sampling chamber 2011, can gradually restore the ammonia generation and volatilization process to a state closer to room temperature without damaging the food structure, creating a more representative sampling environment for subsequent gas detection.

[0030] The trigger 203 is used to detect the food temperature within the area enclosed by the sampling chamber 2011. It can be a temperature sensor or a thermistor, used to acquire food temperature information in real time and output corresponding signals to the subsequent control unit, thereby achieving intelligent triggering of the detection process. The detection chamber 301 is connected to the sampling chamber 2011 and is used to receive gas samples introduced by the sampling chamber 2011. The detection chamber 301 can adopt a sealed cavity structure to ensure the stability of the detection environment. An outlet 3011 is provided on the side away from the sampling chamber 2011 for gas discharge after detection. The detector 302 is located inside the detection chamber 301 and is used to detect the ammonia concentration within the detection chamber 301. The detector 302 can be an electrochemical ammonia sensor, a semiconductor gas sensor, or an optical detection device, etc., and this embodiment does not limit this. By directly detecting the ammonia concentration within the detection chamber 301, the degree of food deterioration can be quantified in the form of gas parameters, improving the objectivity of freshness judgment.

[0031] The coordinated operation of the temperature regulator 202, trigger 203, and vacuum assembly 40 effectively avoids invalid or premature sampling under low-temperature conditions. The vacuum assembly 40 will not activate before the food temperature reaches suitable detection conditions, preventing systematic errors caused by insufficient ammonia release during gas extraction. Sampling and detection are only performed after the temperature reaches the preset value, ensuring that the gas sample in the detection chamber 301 more accurately reflects the current freshness of the food. Therefore, the temperature regulator 202 improves the accuracy of freshness detection for chilled and cold chain foods, enhancing the applicability and reliability of the device in complex real-world operating environments.

[0032] Generally, the preset value can be set between 10-30°C. Within this temperature range, microbial metabolism and protein decomposition reactions in food gradually recover, the production and volatilization rate of ammonia significantly increases, and it does not damage the structure and composition of the food, making it suitable as a temperature condition for freshness testing. Furthermore, for chilled meat, seafood, and other cold chain foods, the preset value is preferably set between 15-25°C, for example, around 20°C. This temperature is close to room temperature, which can effectively weaken the inhibitory effect of low temperature on ammonia release, making the test results more representative and stable.

[0033] The extraction assembly 40 can be configured as a miniature air pump, a fan, or a negative pressure suction device, all of which are common solutions in the field. The extraction assembly 40 is electrically connected to the trigger 203. When the trigger 203 detects that the food temperature has reached the preset detection temperature, it controls the extraction assembly 40 to start, ensuring that gas extraction occurs when the food is at a suitable detection temperature. This avoids premature sampling when the temperature is insufficient, preventing detection deviations and enhancing the specificity and consistency of the detection process. Simultaneously, continuous or timed venting after detection effectively reduces residual gas in the sampling chamber 2011 and the detection chamber 301, preventing residual ammonia from interfering with subsequent detection results and improving the reliability and stability of the device during continuous use.

[0034] Furthermore, the food freshness detection device also includes a cleaning component 50, which includes a sliding plate 501 and a driving component 502. The sliding plate 501 is slidably installed in the detection chamber 301 along a first direction via the driving component 502, wherein the first direction is the flow direction of gas in the detection chamber 301. The sliding plate 501 is provided with a through hole 5011, and a temperature regulating component 202 is provided on the side of the sliding plate 501 close to the food. The temperature regulating component 202 and the through hole 5011 are spaced apart in the vertical direction. Specifically, by sliding the sliding plate 501 along the gas flow direction, the gas in the detection chamber 301 can be pushed and guided when the suction component 40 is working. Structurally, this assists in the discharge of residual gas towards the outlet 3011, thereby improving the thoroughness of gas renewal inside the detection chamber 301 and enhancing the stability and reliability of the device during continuous detection.

[0035] The slide plate 501 can be configured as a plate or sheet structure, and its outer contour is adapted to the inner wall of the detection cavity 301 to effectively disturb the gas in the detection cavity 301 during sliding. A through hole 5011 is provided on the slide plate 501. The through hole 5011 is used to maintain gas communication between the sampling cavity 2011 and the detection cavity 301 when the slide plate 501 is in the working position. The diameter and number of through holes 5011 can be set according to the volume of the detection cavity 301 and the gas flow rate requirements. The driving component 502 is used to drive the slide plate 501 to reciprocate along a first direction. It can be in the form of a micro motor, linear actuator, electromagnetic drive 502, or lead screw transmission structure, etc., to realize the directional movement of the slide plate 501 under the control of the control unit. The above driving methods are all common structural forms in the art, and this embodiment does not specifically limit them. The drive unit 502 can control the slide plate 501 to move towards the air outlet 3011 after the test is completed, and work with the air extraction component 40 to quickly discharge the residual gas in the detection chamber 301. Before the next test begins, the slide plate 501 can be reset to the initial position to ensure normal communication between the sampling chamber 2011 and the detection chamber 301, so that the device has good reusability.

[0036] The temperature regulating element 202 can be configured as an electric heating element, a flexible heating film, or an infrared radiation heating element. Preferably, it heats the food surface through thermal radiation, making the temperature distribution on the food surface more uniform and avoiding the adverse effects of local overheating or overcooling on the release of volatile gases. The temperature regulating element 202 and the through hole 5011 are arranged vertically at intervals, so that the food in the sampling chamber 2011 receives a relatively uniform temperature rise throughout the entire enclosed area, which promotes the uniform release of volatile gases such as ammonia on the food surface and enters the detection chamber 301 through the through hole 5011 for detection. Thus, the structure takes into account both the uniformity of temperature regulation and the uniformity of sampling, further improving the accuracy and repeatability of food freshness detection results.

[0037] Further, the driving component 502 includes a first magnetic plate 5021 and a second magnetic plate 5022. The first magnetic plate 5021 is disposed between the sampling chamber 2011 and the detection chamber 301. A first through groove 5023 is recessed on the first magnetic plate 5021, which is directly opposite to the through hole 5011. The second magnetic plate 5022 is disposed at the end of the detection chamber 301 away from the first magnetic plate 5021. A second through groove 5024 is recessed on the second magnetic plate 5022, which is directly opposite to the air outlet 3011. Both the first magnetic plate 5021 and the second magnetic plate 5022 are electromagnets, and their end faces that are close to each other have the same magnetic poles. The sliding plate 501 is a magnetic structure. Specifically, in this embodiment, the driving component 502 of the cleaning assembly 50 is further configured as a magnetic drive structure to achieve the reciprocating sliding of the sliding plate 501 in the detection chamber 301 without introducing a complex mechanical transmission mechanism, thereby improving structural reliability and reducing the risk of wear during long-term use. Both the first magnetic plate 5021 and the second magnetic plate 5022 are configured as electromagnet structures, capable of changing their magnetic characteristics when energized and de-energized, thereby achieving controllable switching of the motion state of the slide plate 501. The slide plate 501 is configured as a magnetic structure, which can be made of ferromagnetic metal material or have magnetic elements embedded in the substrate. The implementation methods of the above magnetic structures are well known to those skilled in the art.

[0038] The first magnetic plate 5021 has a recessed first through groove 5023, which is directly opposite to the through hole 5011 on the slide plate 501, so as to maintain gas communication between the sampling chamber 2011 and the detection chamber 301 when the slide plate 501 is attached to the first magnetic plate 5021; the second magnetic plate 5022 has a recessed second through groove 5024, which is directly opposite to the air outlet 3011 of the detection chamber 301, so that when the slide plate 501 is attached to the second magnetic plate 5022, it can still provide a smooth exhaust channel for the gas in the detection chamber 301.

[0039] During the actual operation, in the detection stage, the first magnetic plate 5021 is in a non-energized state. At this time, the first magnetic plate 5021 and the sliding plate 501 exhibit opposite magnetism, causing the sliding plate 501 to stably adhere to one side of the first magnetic plate 5021 under the magnetic attraction, thereby fixing the sliding plate 501 at the connection position between the sampling chamber 2011 and the detection chamber 301. Since the temperature regulating component 202 is set on the side of the sliding plate 501 close to the food, after the sliding plate 501 is fixed in this position, it can provide a stable installation reference for the temperature regulating component 202, so that it can continuously and evenly heat or keep the temperature of the food in the sampling chamber 2011 during the detection process, which is conducive to the full release of ammonia in the food.

[0040] After the test is completed, the user can power on the first magnetic plate 5021 and the second magnetic plate 5022 by pressing the control button or trigger switch on the main body 10. After power-on, the magnetic poles between the first magnetic plate 5021 and the slide plate 501 become the same, generating a magnetic repulsion force between them, which pushes the slide plate 501 to move towards the outlet 3011 along the first direction, i.e., the gas flow direction. At the same time, since the magnetic poles of the end faces of the first magnetic plate 5021 and the second magnetic plate 5022 that are close to each other are set to be the same, the slide plate 501 will be magnetically attracted by the second magnetic plate 5022 during its forward movement. Thus, under the combined effect of magnetic repulsion and magnetic attraction, the slide plate 501 slides smoothly along the first direction in the detection cavity 301 and finally adheres to the second magnetic plate 5022.

[0041] When the slide plate 501 slides and adheres to the second magnetic plate 5022, the electromagnet is de-energized, and the magnetic poles between the second magnetic plate 5022 and the slide plate 501 return to the same state, generating a magnetic repulsive force between them, causing the slide plate 501 to move in the opposite direction of the first direction. At the same time, since the end faces of the first magnetic plate 5021 and the second magnetic plate 5022 have the same magnetic poles when they approach each other in the de-energized state, the slide plate 501 will be subjected to the magnetic repulsion of the first magnetic plate 5021 during the return stroke and will eventually re-adhere to the first magnetic plate 5021, thereby resetting the slide plate 501 to the initial detection position. Through the aforementioned magnetic switching and reciprocating motion of the slide plate 501, the residual gas in the detection chamber 301 can be effectively disturbed and pushed to the outlet 3011 after the detection is completed, reducing the interference of residual ammonia gas on subsequent detection. At the same time, it can achieve automatic reset without manual intervention. Through this magnetic drive method, the displacement of the slide plate 501 can be achieved without setting up mechanical transmission structures such as slide rail 3013, gears or lead screws, thereby reducing structural complexity and reducing the risk of failure due to mechanical wear.

[0042] Furthermore, the cleaning component 50 also includes an adsorption element 503, which is disposed on the slide plate 501 and used to adsorb residual gas in the sampling chamber 2011 and the detection chamber 301. Specifically, the adsorption element 503 can be made of an adsorption material with good ammonia adsorption performance, such as acid-modified activated carbon, impregnated activated carbon, molecular sieve materials, zeolite materials, or supported chemical adsorption materials. The above-mentioned adsorption materials are all commonly used gas adsorption media 5032 well known to those skilled in the art. The specific structural form of the adsorption element 503 can be strip-shaped, sheet-shaped, or porous block-shaped. It is installed on both sides of the slide plate 501 by fixing, embedding, or covering, so that the adsorption material is fully exposed in the internal space of the sampling chamber 2011 and the detection chamber 301 without affecting the sliding of the slide plate 501, thereby improving its contact area and adsorption efficiency with residual gas.

[0043] Furthermore, the slide plate 501 is provided with a protrusion 5012, which is directly opposite to the temperature regulating component 202. The protrusion 5012 is provided with a vertical groove 5013. The adsorption component 503 includes a guide plate 5031 and an adsorption medium 5032. The guide plate 5031 is slidably installed in the groove 5013. The guide plate 5031 is provided with a receiving cavity 5033, which is directly opposite to the protrusion 5012. The adsorption medium 5032 is disposed in the receiving cavity 5033. Specifically, the slide plate 501 is provided with a protrusion 5012, which can be understood as a structural component protruding from the body of the slide plate 501. Its position is directly opposite to the temperature regulating component 202, and it is used to provide a spatial mounting and guiding foundation for the adsorption component 503.

[0044] During the testing process, the guide plate 5031 is in the receiving position of the slide 5013. At this time, the adsorption medium 5032 is received inside the slide 5013 along with the receiving cavity 5033, so that the receiving cavity 5033 is kept apart from the gas flow area in the sampling cavity 2011 and the detection cavity 301. This effectively prevents the adsorption medium 5032 from adsorbing ammonia gas in advance during the testing stage, thereby preventing the weakening of the ammonia gas concentration in the detection cavity 301. This ensures that the gas parameters obtained by the detector 302 truly reflect the freshness level of the food and improves the accuracy and repeatability of the test results. After the test is completed, the guide plate 5031 slides in the slide 5013, causing the receiving cavity 5033 to move from the receiving position to the working position. At this time, the receiving cavity 5033 is aligned with the through hole 5011 on the slide plate 501. Since the through hole 5011 is the main gas flow channel between the sampling chamber 2011 and the detection chamber 301, when the receiving chamber 5033 is aligned with the through hole 5011, the ammonia gas remaining in the sampling chamber 2011 and the detection chamber 301 can more easily enter the receiving chamber 5033 and fully contact the adsorption medium 5032, thereby significantly improving the adsorption efficiency of the residual gas, effectively reducing the interference of background ammonia gas on subsequent detection, and further improving the stability and reliability of the food freshness detection device in continuous use scenarios.

[0045] Furthermore, the guide plate 5031 is inverted L-shaped and includes a vertical plate 311 and a horizontal plate 312. A receiving cavity 5033 is disposed on the vertical plate 311, and the horizontal plate 312 is fixed to the end of the vertical plate 311. A third magnetic plate 3012 is disposed on the detection cavity 301. The side of the horizontal plate 312 closest to the third magnetic plate 3012 is configured with a magnetic structure. The third magnetic plate 3012 is directly opposite to the horizontal plate 312 and has opposite magnetic poles. Specifically, the third magnetic plate 3012 can be a permanent magnet or an electromagnet structure, and its specific form can be selected according to the overall control requirements. The above-mentioned magnetic structures are all mature technologies in the field, and this embodiment does not impose specific limitations.

[0046] In the actual operation, when the device is in the detection state, the slide plate 501 is fixed in the initial position between the sampling chamber 2011 and the detection chamber 301 under the magnetic attraction of the first magnetic plate 5021. At this time, the guide plate 5031 is in the detection position along with the slide plate 501. Since the third magnetic plate 3012 and the horizontal plate 312 are arranged opposite each other in this position and have opposite magnetic poles, the horizontal plate 312 is stably attracted to the third magnetic plate 3012 under the magnetic attraction, thereby keeping the vertical plate 311 in the upper position of the slide 5013. The adsorption medium 5032 is collected in the slide 5013 along with the receiving cavity 5033. Through this structural arrangement, the adsorption medium 5032 is kept at a distance from the main gas flow area in the sampling chamber 2011 and the detection chamber 301 during the detection stage, effectively preventing the adsorption medium 5032 from adsorbing ammonia gas in advance during the detection process, thereby preventing the ammonia gas concentration in the detection chamber 301 from being weakened, and ensuring that the data obtained by the detector 302 can truly reflect the freshness of the food.

[0047] After the test is completed, the slide plate 501 slides along the first direction under the action of the aforementioned magnetic drive structure. The overall position of the slide plate 501 and the guide plate 5031 changes, causing the third magnetic plate 3012 and the horizontal plate 312 to be misaligned in space. At this time, the magnetic attraction between the two is invalidated or significantly weakened. Due to the release of magnetic constraints, the guide plate 5031 slides down along the slide groove 5013 under its own gravity, causing the receiving cavity 5033 on the vertical plate 311 to move from the storage position to the working position, so that the receiving cavity 5033 and the through hole 5011 on the slide plate 501 are directly opposite each other. Through this position switch, the ammonia gas remaining in the sampling cavity 2011 and the detection cavity 301 can more easily enter the receiving cavity 5033 through the through hole 5011 and come into full contact with the adsorption medium 5032, thereby significantly improving the adsorption efficiency of the residual gas.

[0048] Further, the trigger 203 includes an expansion body 2031, a first conductor 2032, and a second conductor 2033. A groove 2012 is recessed on the side of the housing 201 near the food. The second conductor 2033 is disposed on the bottom surface of the groove 2012. The expansion body 2031 is disposed at the end of the groove 2012 near the food, and the first conductor 2032 is disposed at the end of the expansion body 2031 near the second conductor 2033. When the expansion body 2031 detects that the food temperature reaches a preset value, the first conductor 2032 and the second conductor 2033 are electrically connected. Specifically, the expansion body 2031 is used to sense the surface temperature of the food and undergo volume change according to temperature changes. It can be made of materials with thermal expansion and contraction characteristics, such as thermosensitive expansion materials, wax-based phase change materials, shape memory alloy coating structures, or polymer thermal expansion materials. The above materials and their application methods are conventional techniques well known to those skilled in the art, and this embodiment does not specifically limit them. By placing the expansion body 2031 at the end of the slot 2012 close to the food, it can quickly respond to temperature changes on the food surface, thereby improving the sensitivity and real-time performance of temperature sensing.

[0049] During operation, when the food surface temperature is low, the expander 2031 is in a small initial state. At this time, the first conductor 2032 and the second conductor 2033 are spaced apart, the circuit is open, and the suction assembly 40 will not start. This avoids premature gas extraction before the food temperature reaches the appropriate detection conditions, preventing insufficient ammonia volatilization at low temperatures and thus preventing detection deviations. As the temperature regulator 202 heats or maintains a constant temperature on the food surface, when the food temperature gradually rises and reaches the preset detection temperature, the expander 2031 expands in volume and gradually fills the slot 2012. This causes the first conductor 2032 at its end to move towards the second conductor 2033 until they contact each other and form an electrical connection. This triggers a signal to drive the suction assembly 40 to start. This structure ensures that the suction assembly 40 only starts when the food temperature reaches the appropriate detection conditions, guaranteeing the accuracy and consistency of gas sampling timing.

[0050] Furthermore, the detection cavity 301 is provided with a slide rail 3013 along the first direction, and sliders 5014 are provided on both sides of the slide plate 501. Rolling elements 3014 are slidably installed in the slide rail 3013, and sliders 5014 are slidably installed in the slide rail 3013, with the rolling elements 3014 abutting against the sliders 5014. Specifically, sliders 5014 are provided on both sides of the slide plate 501, and sliders 5014 cooperate with and are slidably installed in the slide rail 3013, so that the movement path of the slide plate 501 in the detection cavity 301 is constrained by the slide rail 3013, thereby preventing the slide plate 501 from deviating, tilting or getting stuck during the sliding process. The sliders 5014 can be integrally formed on both sides of the slide plate 501, or they can be fixedly connected to the slide plate 501. The material can be wear-resistant plastic, metal or composite material, etc. The above structure and material selection are all conventional design methods in the art, and this embodiment does not make specific limitations.

[0051] The rolling element 3014 abuts against the slider 5014 and rolls during the movement of the slider 5014, thereby converting the sliding friction between the slide plate 501 and the slide rail 3013 into rolling friction. The rolling element 3014 can be a ball, roller, or needle roller, and can be confined within the slide rail 3013 by a limiting structure, allowing it to roll along the first direction within the slide rail 3013 without easily dislodging, thus reducing the frictional resistance during the sliding process of the slide plate 501. In practical use, when the slide plate 501 is displaced along the first direction under the action of the magnetic drive structure, the slider 5014 moves linearly within the slide rail 3013 under guiding constraints. The rolling element 3014 rolls between the slider 5014 and the slide rail 3013, enabling the slide plate 501 to smoothly and steadily complete the sliding and resetting actions, reducing the driving force required during the driving process and lowering the risk of structural aging due to friction and wear.

[0052] Furthermore, a third conductor 3015 is provided at one end of the detection cavity 301 near the second magnetic plate 5022, and a fourth conductor 5015 is provided on the slide plate 501. When the slide plate 501 slides to be in contact with the second magnetic plate 5022, the third conductor 3015 and the fourth conductor 5015 are electrically connected. Specifically, after the detection is completed, the slide plate 501 slides along the first direction under the driving force generated by the magnetic switching between the first magnetic plate 5021 and the second magnetic plate 5022. When the slide plate 501 moves to the side near the second magnetic plate 5022 and reaches the preset cleaning endpoint position, the third conductor 3015 in the detection cavity 301 and the fourth conductor 5015 on the slide plate 501 come into contact with each other and form an electrical connection, thereby outputting a trigger signal. The trigger signal is transmitted to the control unit to switch the power-on and power-off states of the first magnetic plate 5021 and the second magnetic plate 5022, so that the first magnetic plate 5021 and the second magnetic plate 5022 change from the power-on state to the power-off state, or cause their magnetic poles to reverse, thereby changing the magnetic force relationship between them and the slide plate 501.

[0053] After the first magnetic plate 5021 and the second magnetic plate 5022 are de-energized or their magnetic poles are reversed, the original magnetic attraction between the slide plate 501 and the second magnetic plate 5022 is released or transformed into magnetic repulsion. Simultaneously, a magnetic force favorable for the return stroke is formed between the slide plate 501 and the first magnetic plate 5021, causing the slide plate 501 to automatically reset to its initial detection position in the reverse direction under the magnetic force. This embodiment eliminates the need for additional position sensors or complex control programs, enabling reliable identification of the sliding endpoint of the slide plate 501 and automatic triggering of the reset action. Structurally, it ensures closed-loop control of the slide plate 501's movement process, preventing the slide plate 501 from remaining in a non-working position and affecting the next detection operation.

[0054] A detection method for a food freshness detection device as described in any one of the above claims, comprising the following steps in sequence: Step S1: Position the sampling component 20 close to the food to be tested, so that the sampling chamber 2011 encloses at least a portion of the food to be tested; Step S2: The trigger 203 detects the food temperature in the area enclosed by the sampling chamber 2011 in real time. When the food temperature reaches the preset detection temperature, a start signal is generated. When the food temperature does not reach the preset detection temperature, the temperature regulator 202 is controlled to adjust the temperature of the food in the area enclosed by the sampling chamber 2011 until the food temperature reaches the preset detection temperature and a start signal is generated. Step S3: According to the start signal, control the gas extraction component 40 to start, and draw the gas related to food volatiles in the sampling chamber 2011 into the detection chamber 301; Step S4: During the process of gas entering the detection chamber 301, the detector 302 detects the ammonia concentration in the detection chamber 301 and outputs the corresponding detection data; Step S5: After the test is completed, the tested gas is discharged through the gas outlet 3011, and the freshness status of the food is judged based on the test data.

[0055] In summary, the food freshness detection device provided in this embodiment enables ammonia to be fully released and accurately sampled under suitable conditions, thereby improving the accuracy, stability, and reliability of continuous use in food freshness detection.

[0056] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A food freshness detection device, characterized in that, The device includes a main body, and a sampling component, a detection component, and a vacuum component sequentially disposed on the main body. The sampling component includes a housing, a temperature regulating component, and a trigger component. The housing is disposed on the main body, and a sampling chamber is recessed at one end of the housing near the food. The temperature regulating component is disposed on the sampling chamber and is used to regulate the food temperature in the area enclosed by the sampling chamber. The trigger component is used to detect the food temperature in the area enclosed by the sampling chamber. The detection assembly includes a detection chamber and a detector. The detection chamber is connected to the sampling chamber. An air outlet is provided on the side of the detection chamber away from the sampling chamber. The suction assembly is used to draw gas from the sampling chamber into the detection chamber and discharge the gas from the air outlet. The detector is disposed in the detection chamber and is used to detect the ammonia concentration in the detection chamber. The suction assembly is electrically connected to the trigger. When the food temperature reaches a preset value, the suction assembly is activated.

2. The food freshness detection device according to claim 1, characterized in that, It also includes a cleaning component, which includes a sliding plate and a drive component. The sliding plate is slidably installed in the detection chamber along a first direction via the drive component, wherein the first direction is the flow direction of gas in the detection chamber. The sliding plate is provided with a through hole, and the temperature regulating component is provided on the side of the sliding plate near the food. The temperature regulating component and the through hole are spaced apart in the vertical direction.

3. The food freshness detection device according to claim 2, characterized in that, The driving component includes a first magnetic plate and a second magnetic plate. The first magnetic plate is disposed between the sampling chamber and the detection chamber. The first magnetic plate has a first through groove recessed therein, which is directly opposite to the through hole. The second magnetic plate is disposed at the end of the detection chamber away from the first magnetic plate. The second magnetic plate has a second through groove recessed therein, which is directly opposite to the air outlet. Both the first magnetic plate and the second magnetic plate are configured as electromagnets and their end faces that are close to each other have the same magnetic poles. The sliding plate is configured as a magnetic structure.

4. The food freshness detection device according to claim 3, characterized in that, The cleaning assembly also includes an adsorption element disposed on the slide plate for adsorbing residual gas in the sampling chamber and the detection chamber.

5. The food freshness detection device according to claim 4, characterized in that, The slide plate is provided with a protrusion, which is directly opposite to the temperature regulating component. The protrusion is provided with a groove in the vertical direction. The adsorption component includes a guide plate and an adsorption medium. The guide plate is slidably installed in the groove. The guide plate is provided with a receiving cavity, which is directly opposite to the protrusion. The adsorption medium is disposed in the receiving cavity.

6. The food freshness detection device according to claim 5, characterized in that, The guide plate is in the shape of an inverted L. The guide plate includes a vertical plate and a horizontal plate. The receiving cavity is disposed on the vertical plate. The horizontal plate is fixed to the end of the vertical plate. A third magnetic plate is disposed on the detection cavity. The side of the horizontal plate near the third magnetic plate is configured with a magnetic structure. The third magnetic plate is disposed opposite to the horizontal plate and has opposite magnetic poles.

7. The food freshness detection device according to claim 3, characterized in that, The trigger includes an expansion body, a first conductor, and a second conductor. The housing has a recessed groove on the side near the food. The second conductor is disposed on the bottom surface of the groove. The expansion body is disposed at the end of the groove near the food. The first conductor is disposed at the end of the expansion body near the second conductor. When the expansion body detects that the food temperature has reached a preset value, the first conductor and the second conductor are electrically connected.

8. The food freshness detection device according to claim 2, characterized in that, The detection cavity is provided with a slide rail along the first direction, and sliders are provided on both sides of the slide plate. A rolling element is slidably installed in the slide rail, and the slider is slidably installed in the slide rail, with the rolling element abutting against the slider.

9. The food freshness detection device according to claim 3, characterized in that, A third conductor is provided at one end of the detection cavity near the second magnetic plate, and a fourth conductor is provided on the sliding plate. When the sliding plate slides to fit against the second magnetic plate, the third conductor and the fourth conductor are electrically connected.

10. A detection method for a food freshness detection device as described in any one of claims 1 to 9, characterized in that, The steps are as follows: Step S1: Arrange the sampling component close to the food to be tested, so that the sampling chamber surrounds at least a portion of the food to be tested; Step S2: The triggering element detects the food temperature in the area enclosed by the sampling chamber in real time. When the food temperature reaches the preset detection temperature, a start signal is generated. When the food temperature does not reach the preset detection temperature, the temperature regulating element is controlled to regulate the temperature of the food in the area enclosed by the sampling chamber until the food temperature reaches the preset detection temperature and a start signal is generated. Step S3: According to the start signal, control the gas extraction component to start, and draw the gas related to food volatiles in the sampling chamber into the detection chamber; Step S4: During the process of gas entering the detection chamber, the detector detects the ammonia concentration in the detection chamber and outputs the corresponding detection data; Step S5: After the test is completed, the gas after testing is discharged through the air outlet, and the freshness status of the food is judged based on the test data.

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