A method for evaluating and controlling migration risk of low-temperature slow-cooking livestock and poultry product packaging materials

Abstract

The application relates to the technical field of food processing control, and discloses a low-temperature slow-cooking livestock and poultry product packaging material migration risk evaluation and control method, which comprises the following steps: injecting food simulation liquid into a packaging containing cavity to be detected, performing mechanical extrusion and vacuum pumping, controlling the ratio of the gas phase area to the projection area of the containing cavity to be not greater than a preset gas phase emptying proportion threshold value, and sealing; placing the sealed sample in a liquid water medium in a forced convection state to heat and cool; extracting the internal simulation liquid, adding chromatographic pure acetonitrile and a solid inorganic salt reagent to separate and obtain an extraction liquid; quantitatively analyzing and converting actual migration amount values, comparing with a safety limit value benchmark, and issuing a disablement instruction when the regulation is not met. The application restores the real boundary heat transfer state through the top gap-free packaging and the forced convection water bath; the detection matrix interference is reduced by using salting-out assisted separation; and finally, the risk material is automatically intercepted through the bottom digital logic, so that an automatic control closed loop from inspection to release is constructed.

Description

Technical Field

[0001] This invention relates to the field of food processing control technology, specifically to a method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products. Background Technology

[0002] Low-temperature slow cooking involves sealing food in vacuum packaging and heating it for an extended period in a controlled warm water environment. During the processing of livestock and poultry products, chemical substances from the packaging materials can migrate into the food under continuous heating. To ensure food safety, it is necessary to test and assess the amount of chemical substance migration from the packaging materials under these conditions.

[0003] Existing migration measurement methods involve injecting the simulated liquid into the packaging and directly placing it in a static water bath for heating. However, these methods have significant drawbacks in practical application. During sample preparation, the conventional direct filling method results in residual gas phase space inside the packaging, preventing the liquid medium from forming complete physical contact with the inner wall. In the subsequent static heating stage, a thick thermal boundary layer forms on the outer surface of the packaging material, causing delayed internal heating and uneven temperature distribution. These static heat transfer conditions cannot replicate the dynamic heat transfer effect of water circulation in actual industrial low-temperature slow cooking equipment, leading to a disconnect between the testing environment and the real processing scenario. Consequently, the measurement results fail to accurately reflect the migration level during actual processing.

[0004] Existing testing procedures often employ conventional liquid-liquid extraction methods when extracting target compounds from simulated solutions. However, when dealing with complex extraction systems, the phase separation boundaries are often blurred, resulting in residual moisture or matrix components in the extracted organic phase. These components can suppress the target ion response signal during analysis using chromatography-mass spectrometry, leading to fluctuations in the final quantitative data. Based on these biased test data, it is difficult for enterprises to accurately determine the true safety risks of packaging materials during production management. Furthermore, it is impossible to automatically implement measures to block non-compliant materials and replace compliant materials when risks exceeding standards are detected. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products. This invention solves the problem that existing testing methods are unable to accurately reproduce the true state of low-temperature slow cooking with no internal gas phase and dynamic external heat transfer, leading to distorted assessment results. At the same time, conventional extraction methods also suffer from defects such as ambiguous phase separation and fluctuating extraction recovery rates.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products, the method comprising the following steps: Calculate the internal surface area parameter of the packaging material to be tested, receive the food simulation liquid parameter, slow cooking temperature parameter and slow cooking time parameter, and inject the food simulation liquid into the receiving cavity of the packaging material to be tested; The packaging material to be tested is subjected to mechanical extrusion and vacuum extraction, and then heat-sealed to form a packaged test sample. The packaged test sample was placed in a liquid water medium under forced convection, and heating was started according to the slow cooking temperature parameters and slow cooking time parameters, and forced cooling was performed after the heating was completed. Extract the food simulation liquid from the heated packaged test sample, add organic solvent and inorganic salt reagent, and perform centrifugation to obtain the target extract. The target extract is tested to obtain mass concentration parameters, and the actual migration amount is calculated by combining the internal surface area parameters. The actual migration amount is compared with the migration safety limit benchmark. If non-compliance is found, a disabling command is sent, and a search is performed from the packaging material safe use database. Based on the search results, a corresponding control command is generated.

[0007] By simulating sample preparation, forced convection heating and forced cooling operations, combined with centrifugal extraction of organic solvents and inorganic salts, and introducing a safety limit comparison and substitute replacement instruction mechanism, this method solves the problem that conventional static immersion testing cannot reflect the thermodynamic characteristics of slow cooking, and achieves objective evaluation and control of the migration amount of packaging materials.

[0008] Furthermore, the steps of performing mechanical extrusion and vacuum extraction to eliminate residual gas phase space inside the packaging material to be tested, and performing heat-sealing to form a packaged test sample, specifically include: Acquire a projected image of the gas phase region inside the packaging material to be tested, and calculate the ratio of the projected area of ​​the gas phase region to the projected area of ​​the cavity of the packaging material to be tested; when the ratio is not greater than a preset gas phase venting ratio threshold, the venting operation is determined to be completed, and a heat-sealing operation is performed at a preset sealing line position close to the edge of the food simulated liquid surface; a heat-sealing operation is performed at a sealing line position within a preset distance range above the food simulated liquid surface, wherein the preset distance range is a specific numerical range determined based on the actual heat-sealing test.

[0009] By using the ratio of projected area to determine the mechanical extrusion and vacuum extraction, the residual gas phase space inside the packaging is emptied to eliminate the air insulation layer, so that the food simulation liquid adheres to the inner surface of the packaging material to be tested, simulating the solid-liquid contact interface in the actual industrial slow cooking process.

[0010] In a preferred embodiment of the present invention, before the step of injecting the food simulation liquid into the containment cavity of the packaging material to be tested based on the parameters of the food simulation liquid, the method further includes: The system retrieves the internally stored simulated liquid volume parameters per unit contact area; multiplies the simulated liquid volume parameters per unit contact area with the internal surface area parameters to obtain the nominal volume parameters of the food simulation liquid to be injected; and injects the food simulation liquid into the receiving cavity of the packaging material to be tested according to the nominal volume parameters.

[0011] By controlling the injection volume of the simulated liquid per unit contact area using the simulated liquid volume parameter, the liquid-solid contact area ratio in the test system is kept consistent, eliminating the calculation deviation of the migration amount per unit area caused by fluctuations in the simulated liquid filling volume.

[0012] Preferably, the step of placing the packaged test sample in a liquid water medium under forced convection and initiating heating according to the slow-cooking temperature parameters and the slow-cooking time parameters specifically includes: Based on the slow cooking temperature parameters and the slow cooking time parameters, the resistance heating component at the bottom of the heating tank and the water circulation pump on the side wall are activated; the water circulation pump drives the liquid water medium to form a circulating flow in the heating tank and weakens the thermal boundary layer attached to the outer surface of the packaged test sample; the temperature difference between different temperature measurement positions of the liquid water medium in the circulating state is controlled to be no greater than the preset temperature deviation threshold.

[0013] A water circulation pump is used to drive the liquid water medium to form a circulating flow. The thermal boundary layer on the outer wall of the test sample is weakened by the shearing effect of the water flow, simulating the convective heat transfer process in a slow-cooking environment, and reducing the measurement error of migration caused by local temperature deviation due to static heat transfer.

[0014] Furthermore, the forced cooling step after heating is completed specifically includes: When the actual running time reaches the slow cooking time parameter value, the power supply circuit of the resistance heating component is cut off and the cold water replacement valve of the heating water tank is opened to inject circulating cooling water into the heating water tank for forced cooling; the cooling rate is controlled to a preset cooling rate parameter until the temperature of the liquid water medium is less than or equal to the preset safe removal temperature threshold, and is continuously maintained for the preset cooling holding time, after which the packaged test sample is removed.

[0015] By injecting circulating cooling water for forced cooling after the set slow cooking time is reached, the high-temperature migration process of substances can be quickly terminated, reducing the detection error caused by the continuous release of migrating substances during the natural cooling phase of the test sample.

[0016] In a preferred embodiment, the step of adding an organic solvent and an inorganic salt reagent to perform centrifugation to obtain the target extract specifically includes: Chromatographically pure acetonitrile and a solid inorganic salt reagent composed of sodium chloride and anhydrous magnesium sulfate were added to the extracted food simulant. The mixing operation was performed according to the preset extraction parameters, recording the specified oscillation speed and oscillation time, so that the food simulant and the acetonitrile system met the phase separation conditions to form an aqueous phase and an acetonitrile-rich phase. The undissolved particles were separated by centrifugation using a refrigerated centrifuge, and the stratified acetonitrile-rich phase was taken as the target extract.

[0017] By utilizing the hydration of inorganic salt ions to reduce the solubility of chromatographically pure acetonitrile in the aqueous phase, the aqueous and organic phases are separated, driving the transfer of the target compound. At the same time, impurities in the matrix are precipitated by cryogenic centrifugation, removing matrix interference during the compound extraction process.

[0018] Preferably, the step of quantitatively analyzing the target extract to obtain the mass concentration parameter of the target compound specifically includes: The target extract is injected into the high-performance liquid chromatography (HPLC) interface, and after separation, it is introduced into the mass spectrometry (MS) detection interface to activate the electrospray ionization source to ionize the target compound. The target ion response is acquired in multiple reaction monitoring (MRM) mode. The chromatographic peaks corresponding to quantitative ion pairs are extracted, and baseline subtraction and peak area integration are performed. The quantitative response value is determined based on the peak area integration value. When the internal standard method is used, the quantitative response value is the ratio of the peak area of ​​the target compound to the peak area of ​​the internal standard. When the internal standard method is not used, the quantitative response value is the peak area of ​​the target compound. The quantitative response value is then substituted into a pre-established standard substance working curve.

[0019] By employing a multi-reaction monitoring mode and combining peak area integration to determine the quantitative response value, the cross-signal response of complex test solution background is eliminated, thereby improving the accuracy of target compound concentration data acquisition.

[0020] Furthermore, the step of calculating the actual migration amount based on the internal surface area parameter specifically includes: The following parameters are obtained: the mass concentration parameter of the target extract, the final volume parameter of the target extract, the total injection volume parameter of the food simulation liquid, the actual sampling volume of the food simulation liquid, the dilution or concentration factor, the method recovery rate, and the internal surface area parameter. The mass concentration parameter is multiplied by the final volume parameter of the target extract to obtain the extracted mass of the target compound in the actual sampled food simulation liquid. The extracted mass is corrected according to the dilution or concentration factor and the method recovery rate. Based on the ratio of the total injection volume parameter of the food simulation liquid to the actual sampling volume of the food simulation liquid, the corrected extracted mass is converted into the total migration mass of the target compound in all food simulation liquids. The total migration mass of the target compound is divided by the internal surface area parameter to obtain the actual migration amount. Before performing the calculation, the internal surface area parameter, the final volume parameter of the target extract, the total injection volume parameter of the food simulation liquid, the actual sampling volume of the food simulation liquid, and the method recovery rate are all verified to be greater than zero. Before performing the division operation, a non-zero threshold check is performed on the internal surface area parameter.

[0021] The total migration mass in all food simulation liquids is obtained by combining the dilution and concentration factor and the method recovery rate for correction and conversion. At the same time, non-zero verification of each parameter is performed before the calculation to prevent division errors caused by abnormal physical parameters.

[0022] In a preferred embodiment of the present invention, the step of comparing the actual migration amount with the migration security limit benchmark and sending a disable command when non-compliance is determined specifically includes: The system retrieves safety limit benchmarks corresponding to the target compound, the category of packaging material to be tested, the category of livestock and poultry product to be evaluated, and the slow cooking conditions from a pre-stored regulatory database. The actual migration amount is compared with the safety limit benchmark. If the actual migration amount is significantly greater than the safety limit benchmark, the result is deemed non-compliant. The material code and production batch of the packaging material to be tested are added to the prohibited list, and a prohibition order is issued. The ratio of the actual migration amount to the safety limit benchmark is determined as the exceedance multiple indicator, and an early warning assessment report containing the exceedance multiple indicator is generated.

[0023] By establishing a mechanism to compare test data with regulatory limits, prohibition orders are issued based on the comparison results, and the migration risk of packaging materials is quantified by the multiple of exceedance index.

[0024] Preferably, the step of retrieving from the packaging material safe use database and generating corresponding control instructions based on the retrieval results specifically includes: The system retrieves records of alternative packaging materials from the safe use of packaging materials database that are applicable to the livestock and poultry product category, the slow cooking temperature parameter, and the slow cooking time parameter corresponding to the livestock and poultry product category parameter to be evaluated, and whose migration evaluation results are compliant. When an alternative packaging material record is found, a replacement instruction containing the alternative packaging material code is generated. When no alternative packaging material record is found, a control instruction to stop the use of the corresponding packaging material is generated, and the currently used slow cooking temperature parameter or slow cooking time parameter is not automatically reduced.

[0025] By generating a stop-use instruction when no alternative packaging material is found, and restricting the system from passing compliance checks by lowering the slow-cooking temperature or shortening the slow-cooking time, the system prevents operations that circumvent packaging material compliance checks at the expense of the intensity of food sterilization heat treatment.

[0026] This invention provides a method for assessing and controlling the migration risk of packaging materials used in the slow-cooking of livestock and poultry products. It offers the following advantages: 1. This invention eliminates the internal residual gas phase space by performing mechanical extrusion and vacuum extraction on the packaging material to be tested, and then places the packaged test sample in a liquid water medium under forced convection to start heating. This can weaken the thermal boundary layer on the outer surface of the packaged test sample, establish a heat transfer model that is consistent with the actual low temperature slow cooking process, and avoid the heat transfer hysteresis error caused by conventional static water bath conditions.

[0027] 2. This invention promotes the separation of two phases in the mixed system by adding chromatographically pure acetonitrile and solid inorganic salt reagents to the extracted food simulation liquid for vortexing and centrifugation, and enriches the target compound in the acetonitrile-rich phase. This reduces the entry of water, inorganic salt particles and suspended particles in the extract into the mass spectrometry detection system, reduces the influence of matrix components on the stability of the target ion response, and improves the repeatability of quantitative analysis of migration.

[0028] 3. This invention compares the actual migration amount with the migration safety limit benchmark, and sends a prohibition instruction and a replacement instruction containing the code of alternative packaging materials when the judgment result is non-compliant. This can prevent the continued use of substandard materials and realize the synchronous circulation and replacement of compliant alternative packaging materials. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the system timing interaction of the present invention; Figure 2 This is a schematic diagram of the method flow of the present invention; Figure 3 This is a dynamic control curve of the residual gas phase ratio in this invention; Figure 4 This is a temperature control curve diagram of the isothermal heating and forced cooling process of the present invention; Figure 5 This is a diagram showing the phase separation kinetics of chemical extraction and salting out according to the present invention. Figure 6 The target ion chromatographic response and integral determination signal diagram of the present invention are shown in Figure (a), which represents the macroscopic chromatographic separation diagram, Figure (b) which represents the target ion characteristic confirmation diagram, and Figure (c) which represents the quantitative integral and peak area calculation diagram. Figure 7 This is a diagram showing the standard substance working curve and quality control mathematical model of the present invention; Figure 8 This is a mapping diagram of the safety boundary and alternative matching of the multidimensional process parameters of the present invention; Figure 9 The following is a multidimensional time-series and logarithmic calculation mapping diagram of physical quantities in an embodiment of the present invention; wherein, (a) the figure shows the temperature change curve over time when the constant temperature heating module performs thermodynamic physical environment control, (b) the figure shows the working curve of the standard substance corresponding to the target compound and the mass concentration conversion relationship graph, and (c) the figure shows the comparison histogram of the actual migration amount value and the migration safety limit benchmark. Figure 10 This is a comparison chart of the range of migration fluctuations in the dual systems of this invention. Detailed Implementation

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

[0031] See attached document Figure 1 This invention provides a migration risk assessment and control system for packaging materials of low-temperature slow-cooked livestock and poultry products. The system may include: The encapsulation module is configured to fill the food simulation liquid into the packaging material to be tested according to the preset simulated liquid volume parameters per unit contact area, perform exhaust heat sealing, and obtain the encapsulation test sample; The constant temperature heating module is configured to receive the packaged test sample, perform water bath heating on the packaged test sample according to the preset slow cooking temperature parameters and slow cooking time parameters, and obtain the heated packaged test sample. The sample extraction module is configured to receive the heated packaged test sample, extract the food simulation liquid from the heated packaged test sample, add inorganic salt reagent and organic solvent to perform centrifugation separation, and obtain the target extract. The analysis and detection module is configured to receive the target extract and, based on the information of the resin layer, adhesive layer, ink layer, and additives contained in the packaging material to be tested, retrieve the complete analytical method record corresponding to the specific target compound; when a complete analytical method record exists, the target extract is detected using a chromatography-mass spectrometry device according to the complete analytical method record to obtain the chromatographic response signal of the specific target compound; when no complete analytical method record exists, the analysis is output. The risk assessment module is configured to receive the chromatographic response signal, calculate the actual migration amount of the target compound by combining the effective contact internal surface area parameter, compare the actual migration amount with the preset migration safety limit benchmark, generate the risk assessment result, and send the risk assessment result to the risk control module. The risk control module is configured to receive risk assessment results; when the risk assessment result is non-compliant, it generates a disabling instruction for the batch of packaging materials to be tested, and retrieves alternative packaging materials that meet the corresponding slow cooking temperature and slow cooking time parameters from a pre-established and migration-tested safe use database of packaging materials, and generates a packaging material replacement instruction; when no alternative packaging materials meet the conditions, it generates a control instruction to stop using the packaging materials for the corresponding livestock and poultry product processing, and sends the control instruction to the production control terminal.

[0032] The packaging module includes a heat-sealing device, providing a physically sealed environment for establishing a fixed contact interface between the food simulation liquid and the packaging material to be tested; a constant-temperature heating module provides a thermodynamic physical environment based on a water bath circulation device; a sample extraction module provides the physical operational basis for multiphase media separation based on a centrifuge; an analysis and detection module provides the hardware basis for chemical signal conversion through the ion source and sensor of the detection instrument; a risk assessment module supports numerical conversion and comparison judgment through processor computing power; and a risk control module performs batch locking of packaging materials, safe use condition retrieval, alternative packaging material matching, and production control command output through a processor, data storage, and industrial communication interface.

[0033] See attached document Figure 2 This invention provides a method for assessing and controlling the migration risk of packaging materials for slow-cooked livestock and poultry products. The method includes the following steps: S1, the encapsulation processing module injects the food simulation liquid into the packaging material to be tested according to the preset unit contact area simulated liquid volume parameters, performs encapsulation state operation with controlled residual gas phase ratio to generate encapsulation test sample, and transfers the encapsulation test sample to the constant temperature heating module. S2, load the preset slow cooking temperature parameters and slow cooking time parameters, perform water bath heating operation on the packaged test sample, obtain the heated packaged test sample, and transfer the heated packaged test sample to the sample extraction module; S3, extract food simulation liquid from the heated packaged test sample, add inorganic salt reagent and organic solvent to the food simulation liquid, perform centrifugation to obtain target extract containing target compound, and send the target extract to the analysis and detection module; S4. Based on the information of the resin layer, adhesive layer, ink layer, and additives contained in the packaging material to be tested, at least one specific target compound is determined from the pre-established target compound analysis method database, and the analysis method record corresponding to the target compound is called. Each analysis method record includes at least the target compound name, Chemical Abstracts Service Registry number, standard substance information, internal standard information, chromatographic column specifications, mobile phase composition, gradient elution program, injection volume, ionization mode, quantitative ion pair, qualitative ion pair, collision energy, retention time, calibration range, and limit of quantitation. When there is no complete analysis method record for the corresponding target compound in the database, the analysis and detection module stops detection and outputs an analysis method missing prompt. The target extract is detected using a chromatography-mass spectrometry device to obtain the chromatographic response signal of the target compound. S5, substitute the chromatographic response signal into the pre-constructed standard working curve to convert it into a mass concentration parameter, calculate the actual migration amount of the target compound based on the mass concentration parameter and the preset contact area parameter, compare the actual migration amount with the preset migration safety limit benchmark, generate a risk assessment result, and send the risk assessment result to the risk control module. S6 generates a batch ban instruction for the packaging material to be tested, a replacement instruction for alternative packaging materials, or a stop-use instruction, and sends the instruction to the production control terminal; when the risk assessment result is compliant, it generates a release instruction that allows the corresponding packaging material to be used according to the slow cooking temperature parameters and slow cooking time parameters.

[0034] See attached document Figure 3 In specific implementations, step S1 provided by the present invention may include the following steps: S11, the encapsulation processing module acquires the physical dimensions of the packaging material to be tested and calculates the inner surface area in contact with the liquid. It receives, via an external input interface, the type of livestock or poultry product expected to contact the packaging material, the fat content range, and the parameters of the food simulation liquid. The food simulation liquid parameters include the type of food simulation liquid and the ethanol volume fraction. The encapsulation processing module only initiates subsequent encapsulation operations when the food simulation liquid parameters match the applicable food contact migration test rules stored in the system. If no food simulation liquid parameters are received or the food simulation liquid parameters do not match the applicable rules, the injection stops and a parameter error message is output. The module then calls the internally stored unit contact area simulation liquid volume parameters and performs a product operation with the inner surface area to obtain the nominal volume parameters of the food simulation liquid to be injected. The formula for calculating the nominal volume of the food simulation liquid is as follows: ; In the formula: The nominal volume of the food simulant liquid is expressed in mL. This represents the preset simulated liquid volume parameter per unit contact area; in this embodiment, the parameter is set to 2.0 mL / dm². 2 ; This represents the inner surface area of ​​the packaging material being tested, in cm². 2 .

[0035] S12, the packaging module injects the food simulation liquid into the cavity of the packaging material under test using a liquid injection pump based on the calculated nominal volume command. After the liquid injection process is completed, the packaging module controls the mechanical clamp to apply physical compression load to the external flexible sidewall of the packaging material under test, and simultaneously starts the vacuum pumping component to suck up the residual gas phase space inside the packaging material under test located above the liquid surface of the food simulation liquid. Under the combined action of external air pressure difference and mechanical compression, the inner wall of the packaging material under test contracts inward and adheres tightly to the free liquid surface of the food simulation liquid. The packaging module acquires the projected image of the gas phase region inside the packaging material under test through the image acquisition device set above the heat sealing station, and calculates the ratio of the projected area of ​​the gas phase region to the projected area of ​​the cavity of the packaging material under test. When the ratio is not greater than 1.0%, it is determined that the venting operation is completed and a topgap-free sealing state is formed. When the ratio is greater than 1.0%, mechanical compression and vacuum pumping continue to be performed until the ratio is not greater than 1.0%.

[0036] S13, under the operating conditions of maintaining a controlled residual gas phase ratio in the packaging state and a negative pressure environment inside the packaging material to be tested, the packaging processing module drives the heat sealing component to press downwards in the vertical direction, positioning it at the preset packaging line position close to the edge of the simulated liquid surface of the food to perform a heat-melting sealing operation. Under the high temperature compressive stress provided by the heat sealing component, the open end of the packaging material to be tested softens or partially melts the heat sealing layers in contact with each other, and forms a continuous sealing area through interface diffusion and molecular chain entanglement, forming a final packaged test sample with an internal residual gas phase region projection area ratio of no more than 1.0%. After the heat sealing operation cycle is completed, the packaging processing module releases the mechanical clamp to release the packaged test sample, triggering the bottom conveying mechanism to transfer the packaged test sample to the sample placement position defined by the positioning grid of the constant temperature heating module, waiting for subsequent thermodynamic processing.

[0037] For the control command generation logic of the heating temperature index and pressing time cycle of the associated heat sealing component in the packaging processing module, those skilled in the art can perform conventional engineering matching and debugging based on the resin substrate melting point index and physical thickness parameters of the packaging material to be tested. The closed-loop adjustment mechanism of the bottom heat sealing process parameters is a well-known technical means in the field of polymer packaging molding.

[0038] To ensure absolute adhesion between the food simulation liquid and the inner surface of the packaging material and to eliminate the thermal boundary, the preset gas phase evacuation ratio threshold is set to a range of 0.5% to 2.0%. This preset gas phase evacuation ratio threshold is the optimal boundary value obtained from multiple thermodynamic heat transfer experiments. When the ratio is greater than the gas phase evacuation ratio threshold, residual air bubbles will hinder local heat transfer. When the ratio is strictly controlled below the gas phase evacuation ratio threshold, it can be considered as achieving the ideal topgap-free body packaging state. After the gas phase evacuation ratio threshold requirement is met, the system performs a heat-sealing operation to form a packaged test sample.

[0039] See attached document Figure 4 In specific implementations, step S2 provided by the present invention may include the following steps: S21, the constant temperature heating module receives the packaged test sample transferred by the bottom conveyor mechanism and places it into the internal heating water tank. It receives the slow cooking temperature parameters and slow cooking time parameters used in the actual production process of the livestock and poultry products to be evaluated through the external input interface. The slow cooking temperature parameter adopts the upper limit of the allowable temperature range of the corresponding production process, and the slow cooking time parameter adopts the upper limit of the allowable duration range of the corresponding production process. The constant temperature heating module directly determines the received slow cooking temperature parameter and slow cooking time parameter as the final slow cooking temperature parameter and final slow cooking time parameter used for migration test, without calculating or compensating for the slow cooking time parameter based on the volume of the packaged test sample. When no slow cooking temperature parameter or slow cooking time parameter is received, the constant temperature heating module stops heating and outputs a process parameter missing prompt.

[0040] S22, the constant temperature heating module starts the resistance heating component at the bottom of the heating water tank and the water circulation pump on the side wall according to the final slow cooking time parameter and the corresponding slow cooking temperature parameter. It controls the temperature of the liquid water medium in the heating water tank to rise to the target constant temperature range and maintain dynamic balance. The packaged test sample is completely immersed in the liquid water medium in a forced convection state under the constraint of gravity and positioning grid. The water circulation pump drives the liquid water medium to form a circulation flow in the inner cavity of the heating water tank through continuous pumping action and weakens the thermal boundary layer attached to the outer surface of the packaged test sample, so that the water bath temperature difference experienced by different positions of the packaged test sample is kept within the preset temperature deviation threshold range. In this embodiment, the preferred range of the preset temperature deviation threshold is 0.5℃ to 1.0℃. Specifically, the temperature difference between different temperature measurement positions in the water tank is controlled to be no greater than 1.0℃. The constant temperature heating module outputs a uniform heat flux to the packaged test sample in the internal negative pressure bonding state by relying on the liquid water medium, so that the packaging material under test and the internal food simulation liquid continuously bear the thermodynamic physical load of the slow cooking process within a specified period.

[0041] S23, the timing component built into the constant temperature heating module synchronously collects the actual running time of the liquid water medium in the target slow cooking temperature range. When the actual running time reaches the set final slow cooking time parameter value, the microcontroller of the constant temperature heating module issues a stop heating command and cuts off the power supply circuit of the resistance heating component. At the same time, the constant temperature heating module opens the built-in cold water replacement valve to inject circulating cooling water into the heating water tank for forced cooling. The cooling rate is controlled by the bottom valve opening program to be 3 to 5°C per minute. When the numerical setting limits the amount of physical temperature gradient change that the packaging material under test can withstand during the cooling stage, after the temperature of the liquid water medium drops below the preset safe removal temperature threshold and is maintained for 5 minutes, the preset safe removal temperature threshold is set to 25°C. The constant temperature heating module triggers the robotic arm component to remove the heated packaging test sample from the water tank and perform surface moisture draining. The automatic conveying mechanism then transfers the heated packaging test sample to the sample extraction module for multiphase separation processing.

[0042] For the proportional-integral-derivative temperature control algorithm for controlling the power output of the resistance heating component in the constant temperature heating module, as well as the data acquisition and calibration process of related temperature sensors, those skilled in the art can perform software programming and hardware selection settings based on the closed-loop feedback mechanism of conventional constant temperature water bath equipment. The underlying temperature will follow and the constant compensation mechanism is a well-known technology in the field of temperature control instruments.

[0043] See attached document Figure 5 In specific implementations, step S3 provided by the present invention may include the following steps: S31, the sample extraction module receives the heated packaged test sample transferred by the automatic conveying mechanism, and uses a disposable sampling needle to puncture the internal cavity of the packaged test sample to extract the heat-treated food simulation liquid and inject it into the first centrifuge tube; the sample extraction module adds chromatographically pure acetonitrile to the first centrifuge tube through a liquid dispenser, and adds a solid inorganic salt reagent composed of sodium chloride and anhydrous magnesium sulfate through a solid sampler. The sampling volume of the food simulation liquid, the volume of acetonitrile added, the mass of sodium chloride added, and the mass of anhydrous magnesium sulfate added are determined by the extraction parameter records that correspond one-to-one with the composition of the food simulation liquid; when there is no extraction parameter record in the system that corresponds to the current composition of the food simulation liquid and has been verified by the spiked recovery test, the sample extraction module stops operating and outputs an extraction parameter missing prompt.

[0044] S32, the sample extraction module controls the mechanical gripper to transfer the first centrifuge tube to the fixed position of the vortex oscillation assembly. It performs a mixing operation according to the oscillation speed and time specified in the extraction parameters, ensuring sufficient contact between acetonitrile, the food simulant, and the solid inorganic salt reagent. Sodium chloride increases the ionic strength of the aqueous phase, and anhydrous magnesium sulfate combines with some of the water in the food simulant. When the food simulant and acetonitrile system meet the phase separation conditions, an aqueous phase and an acetonitrile-rich phase are formed. The target compound enters the acetonitrile-rich phase according to its distribution characteristics between the aqueous and acetonitrile-rich phases. After vortex oscillation, the sample is allowed to stand until a recognizable two-phase interface appears within the first centrifuge tube. If a recognizable two-phase interface does not form within the standing time specified in the extraction parameters, the sample is marked as extraction failed and will not proceed to subsequent quantitative analysis.

[0045] S33, after the vortex mixing process, the sample extraction module sends the first centrifuge tube into a refrigerated centrifuge and performs centrifugation separation according to the specified centrifugation temperature, relative centrifugation force, and centrifugation time recorded in the extraction parameters. After centrifugation, undissolved inorganic salts, packaging material debris, and suspended particles settle to the bottom of the first centrifuge tube. The acetonitrile-rich phase and the aqueous phase form a recognizable phase interface. The sample extraction module drives a micropipette to aspirate the acetonitrile-rich phase and transfer it to a vial. After being filtered through a polytetrafluoroethylene filter membrane with a pore size of 0.22 micrometers, the acetonitrile-rich phase is sent to the analysis and detection module as the target extract.

[0046] For the stepper motor servo drive algorithm that controls the three-dimensional positioning accuracy of the micropipettes in the sample extraction module and the fault feedback mechanism of the dynamic balance detection sensor of the refrigerated centrifuge, the hardware control hierarchy architecture of the conventional automated laboratory pretreatment workstation can be referenced for conventional configuration. The underlying mechanical coordinate system transformation and anti-collision interlocking mechanism are well-known technologies in the field of automated instrumentation and equipment.

[0047] See attached document Figure 6 In specific implementations, step S4 provided by the present invention may include the following steps: S41, the autosampler of the analysis and detection module draws up the target extract and injects it into the high-performance liquid chromatography interface. According to the analysis method corresponding to the target compound, the column temperature, mobile phase flow rate, injection volume and gradient elution program are recorded and controlled to enable the target compound and interfering components to be separated by chromatographic separation based on the difference in retention time.

[0048] S42, after chromatographic separation, the target compound enters the mass spectrometry detection interface along with the mobile phase. The analysis and detection module starts the electrospray ionization source according to the specified positive ion mode or negative ion mode recorded by the analysis method to ionize the target compound. The triple quadrupole mass analyzer collects the target ion response in multiple reaction monitoring mode according to the corresponding parent ion, quantitative daughter ion and qualitative daughter ion parameters, forming target ion chromatographic data of the target compound response intensity as a function of retention time.

[0049] S43, the analysis and detection module extracts the chromatographic peaks corresponding to the quantitative ion pairs from the target ion chromatographic data, identifies the target peaks according to the retention time window specified in the analysis method record, and performs baseline subtraction and peak area integration on the identified target peaks to obtain the peak area integral value as the chromatographic response signal; at the same time, it confirms the identity of the target compound according to the response ratio of the qualitative ion pair and the quantitative ion pair and the allowable deviation range. Chromatographic peaks that do not simultaneously meet the retention time and ion response ratio judgment conditions are not included in the quantitative calculation.

[0050] See attached document Figure 7 In specific implementations, step S5 provided by the present invention may include the following steps: S51, the risk assessment module receives the peak area integral value transmitted by the analysis and detection module through the internal data bus. The risk assessment module calls the standard substance working curve pre-loaded in the solid-state memory, takes the ratio of the peak area of ​​the target compound to the peak area of ​​the corresponding internal standard as the quantitative response value, and substitutes the quantitative response value into the linear regression equation corresponding to the standard substance working curve to calculate the mass concentration of the target compound in the target extract.

[0051] When the internal standard method is not used, the peak area of ​​the target compound is used as the quantitative response value. The system outputs the mass concentration parameter only when the correlation coefficient of the standard curve, the calibration range and the test results of the quality control sample all meet the quality control conditions specified in the analytical method record. Based on the general principles of quantitative analytical chemistry, the slope parameter in the linear regression equation characterizes the physical detection sensitivity of the analytical instrument, and the intercept parameter characterizes the background noise level of the system baseline. The standard material working curve is a mathematical model constructed by fitting the response signals generated by at least five matrix-matched standard solutions with concentration gradients under the same instrument analysis conditions using the least squares method. Each concentration point covers the expected detection concentration range of the target compound in order from low to high, and at least one matrix blank sample without the target compound and one quality control sample located in the middle of the calibration range are set. When the deviation between the measured concentration and the nominal concentration of a quality control sample exceeds the allowable range specified in the analytical method record, the test results of this batch of samples are deemed invalid.

[0052] S52, after the system obtains the mass concentration parameters, the risk assessment module extracts the inner surface area parameters of the packaging material to be tested and the volume parameters of the extraction solvent in the multiphase separation process recorded in the previous stage. The safety verification program at the bottom of the risk assessment module performs a non-zero threshold verification on the inner surface area parameters before performing the division operation to avoid the computer's underlying logic dead zone where the denominator is zero. When the internal surface area parameter is determined to be greater than the preset area threshold set by the system, the risk assessment module calls the underlying migration conversion engine to substitute the parameter into the preset calculation model to perform mapping transformation. Based on the principle of material conservation in the pre-analysis process, it outputs the actual migration value that characterizes the degree of release of chemical substances from the packaging material under test into the food simulation liquid under the simulated slow cooking process.

[0053] The formula for calculating the actual migration amount is as follows: ; In the formula: This represents the calculated actual migration amount, in mg / dm³. 2 ; This represents the mass concentration parameter obtained by calculation using the standard substance working curve, in mg / L. This represents the final volume parameter of the target extract, in L; Indicates the dilution or concentration factor during sample pretreatment; dimensionless. This indicates the total volume of food-simulated liquid injected into the packaged test sample, in milliliters. This indicates the actual volume of simulated liquid food extracted from the packaged test sample, in milliliters. The method recovery rate, as determined by the spiked recovery test, is expressed as a decimal and is dimensionless. This represents the internal surface area parameter of the packaging material being tested, in dm². 2 The preset area threshold for the area parameter is limited to 0.1m. 2 .

[0054] In this embodiment, the dilution or concentration factor is... The volume for the acetonitrile phase separation is the volume of the final volume; the sampling volume is the physical volume of the extract actually extracted from the acetonitrile-rich phase after multiphase centrifugation; the final volume for the final volume adjustment is the physical volume of the liquid after nitrogen blowing evaporation of the extract, adding a reconstitution solvent, and balancing before being placed into the vial; the system adjusts the dilution or concentration factor according to the physical ratio of the final volume adjustment volume to the sampling volume. The value range is limited to 1.0 to 5.0.

[0055] S53, the risk assessment module imports the calculated actual migration amount into the preset safety assessment rule library for slow-cooking food contact materials, and performs a Boolean logic comparison between the numerical values ​​and the migration safety limit benchmarks of the corresponding target compounds retrieved from the built-in regulatory database. Only when the target compound identification conditions, standard curve quality control conditions, sample extraction quality control conditions, limit application conditions, and limit unit consistency conditions are all met, and the actual migration amount is less than or equal to the corresponding safety limit, the risk assessment module generates a digital quality inspection report marked as compliant. If any condition is not met, an invalid test report, missing parameters, or an inability to determine the result will be generated, and a compliance report will not be generated. When the actual migration amount is significantly greater than the migration safety limit benchmark, the risk assessment module will trigger the system's audible and visual alarm component and simultaneously generate an early warning assessment report containing the types of items exceeding the standard and the multiples of exceeding the standard. The final risk assessment result will be automatically pushed to the operation interface terminal display of the relevant quality control personnel by the central control terminal through the industrial communication bus.

[0056] For the embedded relational database architecture for data storage and report generation in the risk assessment module, as well as the graphical user interface rendering mechanism of the interface display terminal, those skilled in the art can refer to the data management specifications of conventional industrial control computers for system component configuration. The underlying high-concurrency transaction data processing rules and the asynchronous refresh display logic of the front-end human-computer interaction interface are well-known technologies in the field of computer software engineering.

[0057] See attached document Figure 8 In a specific implementation, step S6 provided by the present invention includes the following steps: S61, the risk control module receives the risk assessment result sent by the risk assessment module, and reads the material code, production batch, applicable livestock and poultry product category, slow cooking temperature parameter and slow cooking time parameter corresponding to the packaging material to be tested; when the risk assessment result is non-compliant, the corresponding material code and production batch are written into the prohibited list, and a prohibition instruction is sent to the production control terminal.

[0058] S62, the risk control module retrieves records of alternative packaging materials from the packaging material safety use database that are applicable to the same livestock and poultry product category, slow cooking temperature parameters, and slow cooking time parameters, and whose migration evaluation results are compliant; when an alternative packaging material record is retrieved, a replacement instruction containing the alternative packaging material code, applicable temperature range, applicable time range, and verification report number is generated and sent to the production control terminal.

[0059] S63, when no record of a suitable alternative packaging material is found, the risk control module generates a control instruction to stop the use of the corresponding packaging material, without automatically reducing the slow cooking temperature or shortening the slow cooking time; only after the new slow cooking process parameters have completed food safety verification and packaging material migration verification can the new slow cooking process parameters be written into the packaging material safe use database and the disabled status be lifted.

[0060] See attached document Figure 9 To aid in understanding the technical solution of this invention, the following is an application example that uses a polyamide and polyethylene composite packaging bag for slow-cooked black pepper beef products as the packaging material to be tested, and conducts risk assessment and control of caprolactam monomers that migrate in the polyamide layer.

[0061] The packaging processing module receives external input physical dimension data of the packaging material to be tested, including preset length and preset width. The packaging processing module performs a product operation on the length and width and multiplies it by a double-sided coefficient to calculate the initial inner surface area value of the packaging material to be tested. After converting to standard units, the standard inner surface area value is obtained.

[0062] The system matches and selects an ethanol-water solution with a first preset volume fraction as the food simulation liquid based on the externally input beef product fat content parameter from the rule base. The encapsulation processing module calls the unit contact area simulation liquid volume parameter, multiplies the unit contact area simulation liquid volume parameter with the standard inner surface area value to obtain the nominal volume of the food simulation liquid to be injected.

[0063] The encapsulation module uses a liquid injection pump to inject a nominal volume of food-simulated liquid into the packaging material to be tested, performing mechanical extrusion and vacuum extraction. The image acquisition unit determines that the ratio of the projected area of ​​the internal gas phase region to the projected area of ​​the containment cavity meets the preset zero-gap ratio threshold, which is set to ≤1%. After the zero-gap encapsulation state determination condition is met, the encapsulation module drives the heat sealing component to complete the preparation of the encapsulated test sample.

[0064] The constant temperature heating module receives the packaged test sample and receives the first slow cooking temperature parameter and the first slow cooking time parameter input from the outside. The constant temperature heating module controls the liquid water medium in the heating water tank to rise to the target temperature corresponding to the first slow cooking temperature parameter. The water circulation pump maintains the closed-loop flow of the liquid water medium. After the timing component records the actual heating time and the first slow cooking time parameter is reached, the constant temperature heating module cuts off the power supply to the resistance heating component and injects circulating cooling water to cool the packaged test sample to room temperature.

[0065] The sample extraction module extracts a preset extraction volume of food simulation liquid from the heated packaged test sample and injects it into the first centrifuge tube. A preset extraction volume of chromatographically pure acetonitrile is added, along with a solid inorganic salt reagent composed of sodium chloride and anhydrous magnesium sulfate. After the mixed system is separated by vortexing and freeze centrifugation, the sample extraction module aspirates the upper pure acetonitrile-rich phase to obtain the target extract. The actual volume parameters of the pure organic solvent extracted in the multiphase separation process are recorded, along with the physical concentration and dilution conversion factors.

[0066] The analysis and detection module calls the chromatographic and mass spectrometric analysis method corresponding to caprolactam to record the peak area integral value of the target compound for quantitative analysis of the target extract. The risk assessment module substitutes the peak area integral value into the linear regression equation of the pre-established standard substance working curve and obtains the initial mass concentration parameter through inverse calculation.

[0067] The risk assessment module calls the underlying migration conversion engine to multiply the initial mass concentration parameter with the actual extracted pure organic solvent volume parameter. The first value obtained by multiplying is multiplied by the physical concentration and dilution conversion factor to obtain the intermediate mass value. Then, the intermediate mass value is divided by the standard internal surface area value to finally obtain the actual migration value.

[0068] The risk assessment module retrieves the safety limit benchmark for caprolactam from the built-in regulatory database. The risk assessment module determines that the actual migration amount is less than the safety limit benchmark through Boolean logic comparison. The risk assessment module generates a digital quality inspection report marked as compliant. The risk control module receives the compliance determination result and generates a release instruction that allows the polyamide and polyethylene composite packaging bags to be put into production and used according to the established process parameters. The risk control module sends the release instruction to the production control terminal.

[0069] See attached document Figure 10 The first test group used the system provided by this invention to perform an automated test process, while the second test group used a static water bath plus artificial liquid-liquid extraction to perform a control test process.

[0070] The test subjects were polyamide and polypropylene composite packaging bags with consistent production batches and physical thicknesses. The target compound was a phthalate target compound. The packaging materials were randomly divided into a first test group and a second test group. The slow cooking temperature parameter of the first test group and the second test group were set to the second slow cooking temperature parameter. The slow cooking time parameter of the first test group and the second test group was set to the second slow cooking time parameter. The food simulation liquid added to the first test group and the second test group was an ethanol aqueous solution with a second preset volume fraction.

[0071] In the first test group, the constant temperature heating module maintained the forced convection heat transfer physical conditions through a water circulation pump, the sample extraction module performed anti-emulsification salting-out assisted extraction and freeze centrifugation separation, and the analysis and detection module completed signal conversion and quantitative calculation through a chromatography-mass spectrometry device.

[0072] In the second test group, no forced water circulation device was installed inside the static water bath. The experimenters performed the liquid-liquid extraction step by manually shaking the separatory funnel. The centrifugation was performed at a preset speed using a conventional benchtop centrifuge at room temperature. The extract was collected using the same chromatography-mass spectrometry equipment. The risk assessment module simultaneously recorded the actual migration values ​​obtained from the first and second test groups.

[0073] The experimental records show that the distribution of migration values ​​obtained by the second test group exhibits the first range interval, while the distribution of migration values ​​obtained by the first test group exhibits the second range interval. The range of migration values ​​output by the first test group is much smaller than that of the second test group, and the data concentration of the first test group is higher than that of the second test group.

[0074] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these specific embodiments are merely illustrative. Those skilled in the art can omit, substitute, and modify the details of the above methods and systems in various ways without departing from the principles and essence of the present invention. For example, combining the above method steps to perform substantially the same function and achieve substantially the same result using substantially the same method falls within the scope of the present invention.

Claims

1. A method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products, characterized in that, Includes the following steps: Calculate the internal surface area parameter of the packaging material to be tested, receive the food simulation liquid parameter, slow cooking temperature parameter and slow cooking time parameter, and inject the food simulation liquid into the receiving cavity of the packaging material to be tested; The packaging material to be tested is subjected to mechanical extrusion and vacuum extraction, and then heat-sealed to form a packaged test sample. The packaged test sample was placed in a liquid water medium under forced convection, and heating was started according to the slow cooking temperature parameters and slow cooking time parameters, and forced cooling was performed after the heating was completed. Extract the food simulation liquid from the heated packaged test sample, add organic solvent and inorganic salt reagent, and perform centrifugation to obtain the target extract. The target compound in the target extract is detected to obtain the mass concentration parameter of the target compound, and the actual migration amount is calculated by combining the internal surface area parameter. The actual migration amount is compared with the migration safety limit benchmark. If non-compliance is found, a disabling command is sent, and a search is performed from the packaging material safe use database. Based on the search results, a corresponding control command is generated.

2. The method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products according to claim 1, characterized in that, The steps involved in forming a packaged test sample by mechanically extruding and vacuuming the packaging material to be tested, followed by a heat-sealing operation, specifically include: Acquire a projected image of the gas phase region inside the packaging material to be tested, and calculate the ratio of the projected area of ​​the gas phase region to the projected area of ​​the cavity of the packaging material to be tested; When the ratio is not greater than the preset gas phase evacuation ratio threshold, the evacuation operation is determined to be completed, and a heat-sealing operation is performed at the preset sealing line position close to the edge of the food simulation liquid surface. A heat-sealing operation is performed at a sealing line position located within a preset distance range above the surface of the simulated food liquid. The preset distance range is a specific numerical range determined based on actual heat-sealing tests.

3. The method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products according to claim 1, characterized in that, Before the step of injecting the food simulation liquid into the receiving cavity of the packaging material to be tested, the method further includes: Call the internally stored parameters of the simulated liquid volume per unit contact area; The nominal volume parameter of the simulated liquid per unit contact area is obtained by multiplying the internal surface area parameter. The food simulation liquid is injected into the cavity of the packaging material to be tested according to the nominal volume parameters.

4. The method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products according to claim 1, characterized in that, The step of placing the packaged test sample in a liquid water medium under forced convection and initiating heating according to the slow-cooking temperature and slow-cooking time parameters specifically includes: Based on the slow cooking temperature parameters and the slow cooking time parameters, the resistance heating component at the bottom of the heating tank and the water circulation pump on the side wall are activated. The water circulation pump drives the liquid water medium to circulate in the heated water tank, thereby weakening the thermal boundary layer attached to the outer surface of the packaged test sample. The temperature difference between different temperature measurement points of the circulating liquid water medium is controlled to be no greater than a preset temperature deviation threshold.

5. The method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products according to claim 1, characterized in that, The step of forced cooling after heating is completed specifically includes: When the actual running time reaches the value of the slow cooking time parameter, the power supply circuit of the resistance heating component installed in a heating water tank is cut off, and the cold water replacement valve installed in the heating water tank is opened to inject circulating cooling water into the heating water tank for forced cooling. The cooling rate is controlled to a preset cooling rate parameter until the temperature of the liquid water medium is less than or equal to the preset safe removal temperature threshold, and is continuously maintained for the preset cooling holding time, at which point the packaged test sample is removed.

6. The method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products according to claim 1, characterized in that, The step of adding organic solvent and inorganic salt reagent to perform centrifugation to obtain the target extract specifically includes: Chromatographically pure acetonitrile and a solid inorganic salt reagent consisting of sodium chloride and anhydrous magnesium sulfate were added to the extracted food simulation liquid. The mixing operation is performed according to the preset extraction parameters, recording the specified oscillation speed and oscillation time, so that the food simulation liquid and the acetonitrile system meet the phase separation conditions to form an aqueous phase and an acetonitrile-rich phase. Undissolved particles were settled by centrifugation using a refrigerated centrifuge, and the separated acetonitrile-rich phase was collected as the target extract.

7. The method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products according to claim 1, characterized in that, The step of detecting the target compound in the target extract and obtaining the mass concentration parameter of the target compound specifically includes: The target extract is injected into the high-performance liquid chromatography interface, and after separation, it is introduced into the mass spectrometry detection interface to start the electrospray ionization source to ionize the target compound. The target ion response is collected in the multiple reaction monitoring mode. Extract the chromatographic peaks corresponding to quantitative ion pairs, perform baseline subtraction and peak area integration, and determine the quantitative response value based on the peak area integration value; When the internal standard method is used, the quantitative response value is the ratio of the peak area of ​​the target compound to the peak area of ​​the internal standard. When the internal standard method is not used, the quantitative response value is the peak area of ​​the target compound; Substitute the quantitative response value into the pre-established standard substance working curve.

8. The method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products according to claim 1, characterized in that, The steps for calculating the actual migration amount based on the internal surface area parameter specifically include: The mass concentration parameter of the target extract, the final volume parameter of the target extract, the total injected volume parameter of the food simulation liquid, the actual sampling volume of the food simulation liquid, the dilution or concentration factor, the method recovery rate, and the internal surface area parameter are obtained. Multiply the mass concentration parameter by the final volume parameter of the target extract to obtain the extraction mass of the target compound in the actual sampled food simulation liquid; The extraction mass is corrected according to the dilution or concentration factor and the method recovery rate, and the corrected extraction mass is converted into the total migration mass of the target compound in the entire food simulation liquid according to the ratio of the total injection volume parameter of the food simulation liquid to the actual sampling volume of the food simulation liquid. The actual migration amount is obtained by dividing the total migration mass of the target compound by the internal surface area parameter. Before performing the calculation, the internal surface area parameter, the final volume parameter of the target extract, the total injected volume parameter of the food simulation liquid, the actual sampling volume of the food simulation liquid, and the method recovery rate are all verified to be greater than zero. Before performing the division operation, the inner surface area parameter is checked for non-zero threshold.

9. The method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products according to claim 1, characterized in that, The step of comparing the actual migration amount with the migration security limit benchmark and sending a disable command when non-compliance is determined specifically includes: Retrieve safety limit benchmarks corresponding to the target compound, the category of packaging material to be tested, the category of livestock and poultry product to be evaluated, and the slow cooking conditions from a pre-stored regulatory database, and compare the actual migration value with the safety limit benchmark value. When the actual migration amount is significantly greater than the safety limit benchmark, the result is deemed non-compliant. The material code and production batch of the packaging material to be tested are added to the prohibited list, and a prohibited order is issued. The ratio of the actual migration amount to the safety limit benchmark is determined as the exceedance multiple index, and an early warning assessment report containing the exceedance multiple index is generated.

10. The method for assessing and controlling the migration risk of packaging materials for low-temperature slow-cooked livestock and poultry products according to claim 1, characterized in that, The step of retrieving from the safe use database of packaging materials and generating corresponding control instructions based on the retrieval results specifically includes: Retrieve from the Packaging Material Safety Use Database records of alternative packaging materials that are applicable to the livestock and poultry product category, the slow cooking temperature parameter, and the slow cooking time parameter corresponding to the livestock and poultry product category parameters to be evaluated, and whose migration evaluation results are compliant; When a record of alternative packaging materials is retrieved, a replacement instruction containing the code of the alternative packaging material is generated; When no alternative packaging material record is found, a control command is generated to stop the use of the corresponding packaging material, and the currently used slow cooking temperature parameter or slow cooking time parameter is not automatically reduced.

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