A system and method for monitoring the microenvironmental gas composition of an aquatic product freezer

Abstract

The present application belongs to the technical field of aquatic product refrigeration house, and particularly relates to an aquatic product refrigeration house micro-environment gas component monitoring system and method. In the system, the MEMS gas detection module is used to realize real-time online monitoring of the gas component of sample gas in the micro-environment of the aquatic product refrigeration house; the temperature monitoring and position module is used to monitor the temperature information and position information in the aquatic product storage process in real time; the information gathering and adaptive analysis processing module is used to analyze and determine the gas component signal monitored by the MEMS gas detection module, and establish an aquatic product quality marker gas component database, and at the same time, an analysis prediction model is constructed by combining the position, temperature and gas concentration threshold value to regulate and control the micro-environment of the refrigeration house; the early warning and regulation module is used to generate an early warning signal according to the abnormal information of the cold chain transportation, and notify the user or manager to regulate and control the aquatic product refrigeration house; the information interaction module is used to display the information of each module in real time.

Description

Technical Field

[0001] This invention belongs to the field of aquatic product cold storage technology, specifically relating to a microenvironment gas composition monitoring system and method for aquatic product cold storage. Background Technology

[0002] Aquatic products, as an important source of protein, occupy a significant position in the dietary consumption structure of Chinese residents. They are widely loved for their rich nutrition, delicious taste, and balanced nutritional profile. With the continuous improvement of income levels among Chinese residents, the demand for freshness in aquatic products is increasing, and the preservation of aquatic products directly affects the economic benefits of production enterprises. Under these circumstances, cold storage technology for low-temperature preservation of aquatic products has come into focus and is being widely applied.

[0003] In recent years, national development plans have put forward new requirements for the development of modern service industries and energy conservation and environmental protection. Currently, my country's gas monitoring technology for aquatic product cold storage facilities is relatively backward. The Internet of Things (IoT) can be used to rationally monitor and manage the microenvironment of cold storage gases, giving the aquatic product cold storage industry a broader development prospect. Traditional gas chromatography is large in volume and slow in detection speed, making it difficult to use in online monitoring via the IoT. Furthermore, hexane, chloroform, cyclohexene, 3-methylbutanal, 3-methylbutanol, trimethylamine, and other characteristic gases of aquatic product spoilage are difficult to detect using relevant gas sensors. Summary of the Invention

[0004] To overcome the problems in the prior art, this invention proposes a microenvironment gas composition monitoring system and method for aquatic product cold storage.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is as follows:

[0006] In a first aspect, the present invention provides a microenvironment gas composition monitoring system for aquatic product cold storage, comprising:

[0007] The MEMS gas detection module is used to realize real-time online monitoring of the gas composition of samples in the microenvironment of aquatic product cold storage.

[0008] The temperature monitoring and location module is used to monitor the temperature and location information of aquatic products in real time during the storage process, and transmit all information to the information aggregation and adaptive analysis and processing module.

[0009] The information aggregation and adaptive analysis and processing module is used to analyze and determine the gas component signals monitored by the MEMS gas detection module, and to establish a database of gas components that are indicative of aquatic product quality. At the same time, it uses location, temperature and gas concentration thresholds to build an analysis and prediction model to regulate the microenvironment of the cold storage.

[0010] The early warning and control module is used to generate alarm signals based on abnormal information in cold chain transportation, and notify users or managers to control the cold storage of aquatic products.

[0011] The information interaction module is connected to the MEMS gas detection module, the temperature monitoring and location module, the early warning and control module, and the information aggregation and adaptive analysis and processing module, respectively, and is used to display the information of each module in real time.

[0012] Furthermore, the MEMS gas detection module includes a MEMS front-end device and a MEMS main device connected to the MEMS front-end device;

[0013] The MEMS front-end device includes a pH sensor and a micro pre-concentration injection device. The pH sensor is used to detect the pH value, and the micro pre-concentration injection device is used to enrich the gas components in the cold storage. After the detected pH reaches a preset threshold, the micro pre-concentration injection device is activated to realize subsequent monitoring of the gas environment.

[0014] The MEMS main device includes a carrier gas module, a micro-chromatographic column module, and a micro-sensor module. The carrier gas module is used to enrich the gas components in the cold storage by the pre-concentration injection device and pump them into the micro-chromatographic column module. The micro-chromatographic column module is used to adsorb and separate the gas components. The micro-sensor module is used to analyze the separated gas components and represent the gas components using weak electrical signals.

[0015] Furthermore, the micro-chromatographic column module includes a gas inlet, two independent square chromatographic channels, one non-chromatographic channel, and a gas outlet; the chromatographic channels are filled with polar and non-polar stationary phases; the non-chromatographic channel is not filled with stationary phase, and the gas components enter the micro-sensor module directly without chromatographic separation after passing through the non-chromatographic channel.

[0016] Furthermore, the information aggregation and adaptive analysis and processing module includes an information aggregation unit, a gas component determination unit, and an analysis, prediction, and control unit connected in sequence.

[0017] The information aggregation unit is connected to the micro sensor module and the temperature monitoring and position module. It collects the gas signals collected by the MEMS gas detection module and the temperature and position information collected by the temperature and position module. The collected information is then transmitted to the gas component determination unit and the analysis, prediction and control unit.

[0018] The gas component determination unit is used to analyze and determine gas signals, analyze the standard gas components that indicate quality changes, establish a one-to-one correspondence between gas types and retention times, and establish a database of gas components that indicate the quality of aquatic products.

[0019] The analysis, prediction, and control unit is used to construct an analysis and prediction model to control the microenvironment of the cold storage by combining information collected by temperature monitoring and location modules with gas concentration threshold information.

[0020] Furthermore, the gas component determination unit uses a gas component determination module to determine the quality marker gases of aquatic products, analyzing and determining the monitored gas component time and intensity signals. The gas component determination module is represented by a gas component factor set X, a concentration level V, and a weight B.

[0021] X = {x1, x2, ..., x} n}

[0022] V = {v1, v2, v3, v4, v5}

[0023] B = {b1, b2, ..., b} n}

[0024] Where X is the factor set of the gas composition, x1, x2, ..., x3. n Let V represent the n influencing indicators of the gas being measured; V be the concentration of the gas being measured, which is divided into five levels according to different gas concentration thresholds: v1, v2, v3, v4, v5; and B be the set of weight vectors for influencing factors, b1, b2, ..., b n This is the element weight vector.

[0025] Furthermore, the gas composition determination unit specifically includes the determination of the characteristic gases for aquatic product quality, including:

[0026] Standardized sample variables are obtained by data standardization of m evaluation indicators and n sample variable values. And obtain standardized indicator variables

[0027]

[0028]

[0029] in,

[0030] In the formula, x ij s represents the sample variable. j Indicates the sample standard deviation. x represents the sample mean of the j-th indicator; i Indicates the indicator variable, The sample mean of the i-th indicator;

[0031] Constructing the correlation coefficient matrix of process data R = (r ij ) m×m With correlation coefficient r ijAnd obtain its eigenvalue λ j eigenvector A j and variance contribution rate b j :

[0032]

[0033]

[0034]

[0035]

[0036] Calculate the cumulative contribution rate μ of m components. p And retain the key components when they accumulate to 90%;

[0037]

[0038] The information on the indicative gaseous components of aquatic product quality, including type, concentration, and retention time (RT), is analyzed using score maps and stored in a database.

[0039] Furthermore, the analytical prediction model includes:

[0040]

[0041] In the formula: C t The content of physicochemical indicators of aquatic products after storage time t represents the initial content of physicochemical indicators of aquatic products; k represents the constant of the rate of quality decline; t represents the storage time; a and b are constants; f(x) is the quality change index: a0, a1, ... a n Here, x represents constants, and x represents influencing factors: oxygen concentration, carbon dioxide concentration, nitrogen concentration, and temperature of the microenvironment; T represents absolute temperature; k1 represents the rate constant; R represents the gas constant; and E represents the gas constant. a It represents the activation energy of the reaction.

[0042] Finally, a coupled model of the indicative gas components and physicochemical indicators of changes in the microenvironment of cold storage was obtained:

[0043]

[0044] Secondly, the present invention also provides a method for monitoring the gas composition of the microenvironment in a cold storage for aquatic products, comprising the following steps:

[0045] The MEMS gas detection module monitors the gas component signals of the microenvironment in the cold storage of aquatic products, including the pH sensor being activated to collect pH data.

[0046] The temperature monitoring and location module monitors the temperature and location information of aquatic products in real time during the storage process.

[0047] Determine whether the pH data monitored by the pH sensor has reached the threshold: if it has, start the micro pre-concentration injection device to pump the carrier gas into the micro chromatography column module, and the micro chromatography column module adsorbs and separates each gas component.

[0048] The miniature sensor module analyzes the separated gas components and represents the gas components using weak electrical analog signals.

[0049] The information aggregation and adaptive analysis and processing module analyzes and judges the monitored gas component signals, converts the time and intensity signals of gas components monitored by the micro-sensor module into the actual types and concentrations of each gas, establishes a database of gas components that are indicative of aquatic product quality, and constructs an analysis and prediction model by combining temperature and location information with gas concentration thresholds to regulate the microenvironment of the cold storage.

[0050] The analysis, prediction and control module stores multiple preset programs and obtains the trend of gas environment changes based on the analysis and prediction model. It also controls the environmental parameters of the cold storage microenvironment according to different levels of gas concentration thresholds.

[0051] The early warning and control module notifies users and automatically adjusts relevant parameters in the cold storage. The actual types, concentrations, and temperature data of each gas component, as well as alarm and early warning information, are all displayed in the information interaction module.

[0052] Furthermore, when the collected gas composition information and environmental information such as temperature are processed by the analysis, prediction, and control module to obtain a gas concentration threshold that reaches a preset gas concentration, relevant control methods are proposed based on different gas concentration threshold levels. These control methods include:

[0053] (1) Determine the parameters of the controlled atmosphere equipment, turn on the controlled atmosphere equipment and adjust the concentrations of CO2, O2 and N2;

[0054] (2) Determine the parameters of the refrigeration equipment, turn on the refrigeration equipment, and adjust the micro-environment temperature;

[0055] Once all parameters reach their preset values, the equipment will stop working and automatically shut down.

[0056] Compared with the prior art, the present invention has the following technical effects:

[0057] This invention provides a multi-gas component monitoring system and method for the microenvironment of aquatic product cold storage, enabling the analysis of multiple gas components. Compared to traditional gas chromatography, the pre-concentration device and chromatographic separation capabilities of the system significantly improve the sensor's detection limit for a single gas, allowing for real-time on-site monitoring of gases in the microenvironment during the storage and transportation of aquatic products. It enables trace monitoring of key hazardous gases such as hexane, chloroform, cyclohexene, 3-methylbutanal, 3-methylbutanol, and trimethylamine. This multi-component gas detection device and method integrates micro-chromatographic separation technology, sensor detection technology, and data acquisition and processing into a single micro-multi-component gas detection system. This system can replace multiple gas sensors, providing a reference for the rapid detection of spoilage and deterioration of aquatic products in cold storage and improving the control of microenvironmental parameters. It has profound significance for the development of aquatic product cold storage. Attached Figure Description

[0058] To more clearly illustrate the technical solutions and advantages 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.

[0059] Figure 1 This is a block diagram of the multi-gas component monitoring system for the microenvironment of aquatic product cold storage, according to an embodiment of the present invention.

[0060] Figure 2 This is a schematic diagram of the MEMS part of the microenvironment multi-gas component monitoring system for aquatic product cold storage according to an embodiment of the present invention;

[0061] Figure 3 This is a flowchart illustrating the method for monitoring multiple gas components in the microenvironment of aquatic product cold storage according to an embodiment of the present invention. Detailed Implementation

[0062] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the specific implementation methods, structures, features, and effects of the technical solutions proposed according to the present invention are described in detail below with reference to the accompanying drawings and preferred embodiments. Specific features, structures, or characteristics in one or more embodiments may be combined in any suitable form. Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0063] In one embodiment of the present invention, a microenvironment gas composition monitoring system for aquatic product cold storage is provided. See also... Figure 1The system includes: a MEMS gas detection module, a temperature monitoring and location module, an information aggregation and adaptive analysis and processing module, an early warning and control module, and an information interaction module.

[0064] In this embodiment, the MEMS gas detection module is used to realize real-time online monitoring of the gas composition of sample gas in the microenvironment of aquatic product cold storage.

[0065] The sample gas is a marker gas related to spoilage and decay in the storage of the aquatic products to be tested, as well as a controllable environmental gas; the marker gas includes gaseous components such as aldehydes, alcohols, esters, amines, and organic acids to be tested; the controllable environmental gas includes gaseous components such as oxygen, carbon dioxide, and nitrogen.

[0066] Specifically, the MEMS gas detection module includes a MEMS front-end device and a MEMS main device.

[0067] The MEMS pre-processor includes multiple pH sensors and a miniature pre-concentration injection device, located at a critical location in the cold storage. This critical location is determined by sensory perception and experience, specifically the area with the highest concentration of volatile gases from aquatic products within the cold storage. The miniature pre-concentration injection device utilizes existing technology. The pH sensors detect pH data at the critical location in the cold storage, while the miniature pre-concentration injection device increases the concentration of sample gas components. The pH sensors remain on. Once the pH reaches a preset value, the sample gas is introduced into the miniature pre-concentration injection device, and subsequent devices are activated sequentially. The miniature pre-concentration injection device and the main MEMS unit remain off until the pH reaches the preset value.

[0068] The MEMS master unit is located at the top of the cold storage. It includes a micro-chromatographic column module, a carrier gas module, and a micro-sensor module. The MEMS master unit is connected to the MEMS front-end device through a capillary tube.

[0069] In a specific embodiment, the carrier gas module is used to pump the gas components enriched in the cold storage by the micro pre-concentration injection device into the micro chromatography column module.

[0070] In a specific embodiment, the micro-chromatographic column module is used to adsorb the component gases and separate them.

[0071] The micro-chromatographic column module is fabricated using MEMS technology and is made of silicon using a deep dry etching method. It is suitable for separating the characteristic volatile components of aquatic products. Figure 2As shown in Part B, the micro-chromatographic column module includes a gas inlet, two independent square chromatographic channels, one non-chromatographic channel, and a gas outlet. The two square chromatographic channels are filled with two different phases (polar and non-polar) of stationary phase. Each of the two chromatographic channels and the one non-chromatographic channel is equipped with a solenoid valve to open or close the relevant channel; during system operation, only one solenoid valve is open.

[0072] The gas inlet is the channel through which the sample gas, along with the carrier gas, enters the chromatographic channel and the non-chromatographic channel. The gas outlet is the channel through which the gas components leave the chromatographic channel and the non-chromatographic channel, and it is connected to the miniature sensor module.

[0073] The micro-chromatographic column module also includes a combined micro-heater and a temperature controller. The combined micro-heater is connected to the micro-chromatographic column module to increase the temperature of the micro gas chromatographic column within the module, thereby improving the separation rate and performance of the micro gas chromatographic column. The temperature controller is connected to the combined micro-heater to provide a constant temperature for the micro-chromatographic column chip and to perform programmed temperature control.

[0074] The micro-chromatographic column module also includes a cooler, which is attached to the outer layer of the micro-chromatographic column chip and uses micro-semiconductor cooling.

[0075] In a specific embodiment, the micro-sensor module is connected to the micro-chromatographic column module, and collects and analyzes the parameter information of gas components in the cold storage according to the time information, and represents the components of the sample gas using weak electrical signals.

[0076] The working mechanism of the micro-sensor module lies in the change in surface conductivity caused by surface chemical reactions (the basis of which is gas-gas and gas-solid reactions occurring on the surface of metal oxide semiconductors, in which oxygen ion adsorption-desorption and reaction with reducing monitoring gases play a key role). Different monitoring gas components undergo different chemical reactions, resulting in different electrical signal intensities. The time signal of the gas components is related to the micro-chromatographic column module, which adsorbs and separates the gas components. Different monitoring gas components produce different separation times in the micro-chromatographic column module, correspondingly generating different time signals in the micro-sensor module.

[0077] The miniature sensor module uses a metal-oxide-semiconductor sensor and is fabricated using MEMS technology. The fabrication method includes:

[0078] Step 1: SnO2 is deposited on an Al2O3 substrate with Pt interleaved electrodes to form a tin dioxide nanorod array by grazing angle deposition of electron beam evaporation;

[0079] Step 2: Deposit a metal (gold / platinum) thin film on top of the tin dioxide nanorod array using an ultra-high vacuum DC sputtering system.

[0080] After the test aquatic product spoilage marker gases (aldehydes, alcohols, esters, amines) and controllable environmental gases (oxygen, carbon dioxide, etc.) are passed through a tin dioxide nanorod array, a weak electrical signal change is generated based on the redox reaction.

[0081] Figure 2 This is a schematic diagram of the MEMS (Multi-Gas Component Monitoring) component of a microenvironment monitoring device for aquatic product cold storage, according to an embodiment of the present invention. Figure 2 As shown, A is the MEMS pre-processing unit, including a micro pre-concentration injection device a, a pH sensor b, a gas component inlet c, and a reverse pump g; B is the MEMS gas chromatography section, including a sample pump d, a MEMS concentrated gas container e, a carrier gas f, a ten-way valve h, a MEMS chromatographic column channel i, and a non-chromatographic channel j; C is the micro sensor module, including a metal oxide sensor k.

[0082] After being concentrated by a pre-concentration device, the sample gas is powered by a reverse pump and enters the MEMS concentrated gas container through a capillary tube. A ten-way valve pumps the mobile phase containing the concentrated sample gas and carrier gas (the carrier gas is the gas that carries the sample, and its composition is nitrogen or argon) into the micro-chromatographic column module. The gas flow control module is connected to the injector to control the gas flow rate of the sample gas and the carrier gas.

[0083] In this embodiment, the temperature monitoring and location module is used to monitor the temperature and location information of aquatic products in real time during storage, and transmit all information to the information aggregation and adaptive analysis processing module. Specifically, the aforementioned location refers to the location of the micro pre-concentration injection device; the temperature monitoring and location module includes a location sensor and a temperature sensor, wherein the temperature sensor is used to monitor the temperature information of aquatic products in real time during storage, and the location sensor is used to monitor the location information of aquatic products in real time during storage.

[0084] In this embodiment, the information aggregation and adaptive analysis and processing module is used to analyze and determine the gas component signals monitored by the MEMS gas detection module, and establish a database of gas components that are indicative of aquatic product quality. At the same time, it uses location, temperature and gas monitoring information combined with gas concentration thresholds to construct an analysis and prediction model to regulate the microenvironment of the cold storage.

[0085] Specifically, the information aggregation and adaptive analysis and processing module includes an information aggregation unit, a gas component determination unit, and an analysis, prediction, and control unit.

[0086] The information aggregation unit is connected to the micro-sensor module, temperature monitoring and position module, and completes the signal amplification, acquisition, processing and output of weak electrical signals from each module, and transmits the acquired information to the gas component determination unit and the analysis, prediction and control unit.

[0087] The gas component determination unit is used to analyze and determine the gas signals acquired by the MEMS module. It uses a micro-chromatography module and a micro-sensor module to analyze quality-indicating gas component standards, establishing a one-to-one correspondence between gas types and retention times (RT values), and creating a database of quality-indicating gas components for aquatic products. This database stores gas component information for various aquatic products under different quality conditions, including gas component type, concentration, and retention time. The retention time (RT value) is the time from the start of injection of a separated gas sample component until the maximum concentration of that component appears after column chromatography; that is, the time elapsed from the start of injection until the peak of a chromatographic peak appears. This is called the retention time of that component, denoted by RT, and is usually measured in minutes (min).

[0088] Based on the database of gaseous components that are indicative of aquatic product quality, the time and intensity signals of gaseous components monitored by the micro-sensor module are analyzed and determined. The gaseous component determination module is represented by a gaseous component factor set X, a concentration level V, and a weight B.

[0089] X = {x1, x2, ..., x} n}

[0090] V = {v1, v2, v3, v4, v5}

[0091] B = {b1, b2, ..., b} n}

[0092] Where X is the factor set of the gas composition, x1, x2, ..., x3. n This represents n influencing indicators of the gas being measured; V is the concentration of the gas being measured, divided into five levels according to different gas concentration thresholds: v1, v2, v3, v4, v5. B is the set of weight vectors for influencing factors, b1, b2, ..., b n This is the element weight vector.

[0093] The specific components of the gas composition determination unit for identifying the marker gases of aquatic product quality include:

[0094] 1) Standardized sample variables are obtained by data standardization of m evaluation indicators and n sample variable values. And obtain standardized indicator variables

[0095]

[0096]

[0097]

[0098] Where, x ij s represents the sample variable. j Indicates the sample standard deviation. x represents the sample mean of the j-th indicator; i Indicates the indicator variable, The sample mean of the i-th indicator.

[0099] 2) Construct the correlation coefficient matrix R = (r ij ) m×m With correlation coefficient r ij And obtain its eigenvalue λ j eigenvector A j and variance contribution rate b j :

[0100]

[0101]

[0102]

[0103]

[0104] In the above formula, Let k be the standardized sample variable for the i-th evaluation index. Let λ and A be the standardized sample variables of the k-th sample variable under the j-th evaluation index. j The result is obtained by solving the correlation coefficient matrix R, y1, y2…y m For the corresponding index load vector, a pj For the corresponding indicator weights, represent the process data evaluation indicator weight vector.

[0105] 3) Calculate the cumulative contribution rate μ of the m components. p And retain the key components when they accumulate to 90%;

[0106]

[0107] Finally, the information on the indicative gaseous components of aquatic product quality, including type, concentration, and retention time (RT), was analyzed using score maps and stored in a database.

[0108] In this embodiment, the analysis, prediction and control unit is used to construct an analysis and prediction model to control the microenvironment of the cold storage by combining the information collected by the temperature monitoring and location module with the gas concentration threshold information. When the gas concentration threshold reaches the set minimum gas concentration threshold, the user or manager is notified through the early warning and control module, and relevant control methods are proposed according to different concentration threshold levels.

[0109] Specifically, the analytical and predictive models include:

[0110]

[0111] In the formula: C t The content of physicochemical indicators of aquatic products after storage time t represents the initial content of physicochemical indicators of aquatic products; k represents the constant of the rate of quality decline; t represents the storage time; a and b are constants; f(x) is the quality change index: a0, a1, ... a n Here, are constants, x is an influencing factor: oxygen concentration, carbon dioxide concentration, nitrogen concentration, and temperature of the microenvironment; T represents absolute temperature; k1 represents the rate constant; R represents the gas constant; E a It represents the activation energy of the reaction.

[0112] Obtain a coupled model of the indicative gas components and physicochemical indicators of changes in the microenvironment of cold storage:

[0113]

[0114] In this embodiment, the early warning and control module is used to notify users or managers based on abnormal information and alarm signals generated by the cold chain transportation system, and to control the system through status diagnosis, process adjustment and equipment management.

[0115] In this embodiment, the information interaction module is connected to the MEMS gas detection module, the temperature monitoring and location module, the early warning and control module, and the information aggregation and adaptive analysis and processing module, respectively, and is used to display the category, environmental information, abnormal information, and control signals of the cold chain transportation products in real time.

[0116] In another embodiment of the present invention, a method for monitoring the gas composition of the microenvironment in a cold storage facility for aquatic products is provided, see [link to relevant documentation]. Figure 3 The method monitors sample gases including marker gas components related to spoilage and decay during the storage of the aquatic products under test, as well as controlled environmental gases. The marker gas components include aldehydes, alcohols, esters, amines, organic acids, and other gaseous components; a database of marker gas components for aquatic product quality is established using key component analysis. Controlled environmental gases include oxygen, carbon dioxide, nitrogen, and other gaseous components. The carrier gas is the gas that carries the sample, and its composition is nitrogen or argon. The method specifically includes the following steps:

[0117] The position sensor, pH sensor, and temperature sensor are activated to collect position, pH, and temperature data, respectively. It should be noted that the main MEMS device is in a closed state at the beginning of the main cycle.

[0118] Determine whether the pH data detected by the pH sensor has reached the threshold: if it has, start the micro pre-concentration injection device to enrich the gas components at the relevant locations in the cold storage and record the relevant location information;

[0119] After the gas components are concentrated by the micro pre-concentration injection device, the mobile phase containing the concentrated gas components and carrier gas is pumped into the micro chromatography column module.

[0120] The micro-chromatographic column module adsorbs and separates various gas components, and the micro-sensor module analyzes the separated components and represents the components using weak electrical analog signals.

[0121] The information aggregation and adaptive analysis and processing module analyzes and determines the gas component signals monitored by the MEMS gas detection module, converts the time and intensity signals of gas components monitored by the micro-sensor module into the actual types and concentrations of each gas, establishes a database of gas components that are indicative of aquatic product quality, and constructs an analysis and prediction model based on location, temperature and gas concentration thresholds to regulate the microenvironment of the cold storage.

[0122] The analysis, prediction and control module stores multiple preset programs and obtains the gas environment change trend based on the analysis, prediction and control model, and performs relevant control on the environmental parameters of the cold storage microenvironment according to different levels of gas concentration thresholds;

[0123] The early warning and control module notifies users and automatically adjusts relevant parameters in the cold storage. The actual types, concentrations, and temperature data of each component, as well as alarm and early warning information, are all displayed in the information interaction module.

[0124] In a specific embodiment, the establishment of a database of gaseous components that characterize the quality of aquatic products includes the following steps:

[0125] (1) Experimental determination:

[0126] Aquatic product samples were extracted and numbered at different set storage times (three parallel samples were taken at each set time). The TVBN (Total Volatile Basic Nitrogen) value was determined. Samples with TVBN values ​​exceeding 30 mg / g were selected, and their gaseous components were determined by GC-MS (Gas Chromatography-Mass Spectrometry) under set chromatographic and mass spectrometric conditions according to the CAS database.

[0127] (2) Determination of gas components

[0128] Data processing can eliminate errors caused by differences in the dimensions and magnitudes of various indicators, and standardize the chromatographic analysis data of aquatic product samples to obtain a standardized matrix.

[0129] Standardized sample variables are obtained by data standardization of m evaluation indicators and n sample variable values. And obtain standardized indicator variables

[0130]

[0131]

[0132] in

[0133] In the formula, x ij s represents the sample variable. j Indicates the sample standard deviation. x represents the sample mean of the j-th indicator; i Indicates the indicator variable, The sample mean of the i-th indicator.

[0134] Constructing the correlation coefficient matrix of process data R = (r ij ) m×m With correlation coefficient r ij And obtain its eigenvalue λ j eigenvector A j and variance contribution rate b j :

[0135]

[0136]

[0137]

[0138]

[0139] In the above formula, Let k be the standardized sample variable for the i-th evaluation index. Let λ and A be the standardized sample variables of the k-th sample variable under the j-th evaluation index. j The result is obtained by solving the correlation coefficient matrix R, y1, y2…y m For the corresponding index load vector, a pj For the corresponding indicator weights, represent the process data evaluation indicator weight vector.

[0140] Calculate the cumulative contribution rate μ of m components. p And retain the key components when they accumulate to 90%;

[0141] The gas component determination unit mainly uses the gas component determination module to determine the characteristic gases of aquatic product quality. It analyzes and determines the time and intensity signals of the monitored gas components. The gas component determination module is represented by the gas component factor set X, concentration level V, and weight A.

[0142] X = {x1, x2, ..., x} n}

[0143] V = {v1, v2, v3, v4, v5}

[0144] A = {a1, a2, ..., a} n}

[0145] Where X is the factor set of the gas composition, x1, x2, ..., x3. n Let V represent the n influencing indicators of the gas being measured; V is the concentration of the gas being measured, divided into five levels according to different gas concentration thresholds: v1, v2, v3, v4, v5. B is the set of weight vectors for influencing factors, b1, b2, ..., b n This is the element weight vector.

[0146] (3) Database establishment

[0147] The micro-chromatographic module and micro-sensor module were used to analyze the standard gas components that marked the quality changes, establish a one-to-one correspondence between gas types and retention times (RT values), and store them in the form of a database in the host computer module.

[0148] During system operation, the startup of the micro-sensor module triggers the host computer module, which converts the time and intensity signals of the gas components monitored by the micro-sensor module into the actual types and concentrations of each gas.

[0149] In a specific embodiment, the analysis and prediction model includes:

[0150]

[0151] In the formula: C t The content of physicochemical indicators of aquatic products after storage time t represents the initial content of physicochemical indicators of aquatic products; k represents the constant of the rate of quality decline; t represents the storage time; a and b are constants; f(x) is the quality change index: a0, a1, ... a n Here, are constants, x is an influencing factor: oxygen concentration, carbon dioxide concentration, nitrogen concentration, and temperature of the microenvironment; T represents absolute temperature; k1 represents the rate constant; R represents the gas constant; E a It represents the activation energy of the reaction.

[0152] Finally, a coupled model of the indicative gas components and physicochemical indicators of changes in the microenvironment of cold storage was obtained:

[0153]

[0154] In a specific embodiment, when the gas concentration threshold obtained after processing the collected gas component information and environmental information such as temperature by the analysis, prediction, and control module reaches a preset gas concentration, a relevant control method is proposed based on different gas concentration threshold levels V:

[0155] The early warning module is activated to notify the user and automatically adjust relevant parameters within the cold storage. In this embodiment, the adjustment methods include:

[0156] (1) Determine the parameters of the controlled atmosphere equipment, turn on the controlled atmosphere equipment and adjust the concentrations of CO2, O2 and N2.

[0157] (2): Determine the parameters of the refrigeration equipment, turn on the refrigeration equipment, and adjust the microenvironment temperature.

[0158] Once all parameters reach their preset values, the equipment will stop working and automatically shut down.

[0159] The above 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, and should all be included within the protection scope of the present invention.

Claims

1. A system for monitoring the micro-environmental gas composition of an aquatic product cold store, characterised in that, include: The MEMS gas detection module is used to realize real-time online monitoring of the gas composition of samples in the microenvironment of aquatic product cold storage. The temperature monitoring and location module is used to monitor the temperature and location information of aquatic products in real time during the storage process, and transmit all information to the information aggregation and adaptive analysis and processing module. The information aggregation and adaptive analysis and processing module is used to analyze and determine the gas component signals monitored by the MEMS gas detection module, and to establish a database of gas components that are indicative of aquatic product quality. At the same time, it uses location, temperature and gas concentration thresholds to build an analysis and prediction model to regulate the microenvironment of the cold storage. The early warning and control module is used to generate alarm signals based on abnormal information in cold chain transportation, and notify users or managers to control the cold storage of aquatic products. The information interaction module is connected to the MEMS gas detection module, the temperature monitoring and location module, the early warning and control module, and the information aggregation and adaptive analysis and processing module, respectively, and is used to display the information of each module in real time; The information aggregation and adaptive analysis and processing module includes an information aggregation unit, a gas composition determination unit, and an analysis, prediction, and control unit connected in sequence. The information aggregation unit is connected to the micro-sensor module and the temperature monitoring and position module, collects the gas signals collected by the MEMS gas detection module, and collects the temperature and position information collected by the temperature and position modules, and transmits the collected information to the gas composition determination unit and the analysis, prediction, and control unit. The gas component determination unit is used to analyze and determine the gas signals collected by the MEMS module, establish a one-to-one correspondence between gas types and retention times, and establish a database of gas components that are indicative of aquatic product quality. The analysis, prediction, and control unit is used to construct an analysis and prediction model to control the microenvironment of the cold storage by combining information collected by the temperature monitoring and location module with gas concentration threshold information. The gas component determination unit uses a gas component determination module to determine the characteristic gases of aquatic product quality. It analyzes and determines the time and intensity signals of the monitored gas components. The gas component determination module is represented by a gas component factor set X, a concentration level V, and a weight B. Wherein, X is a set of factors of gas components, x 1 , x 2 ，…，x n n represents the n influencing indicators of the measured gas; V is the concentration of the measured gas, which is divided into five levels according to different gas concentration thresholds: ; B is a set of influence factor weight vectors, is a factor weight vector; The gas component determination unit specifically includes the following steps for determining the quality marker gas of aquatic products: obtaining standardized sample variables by data standardization and centralizing m evaluation index n sample variable value data and obtaining standardized index variables ​ wherein ; In the formula, Represents sample variables. Indicates the sample standard deviation. Indicates the first The sample mean of each indicator; Indicates the indicator variable, No. i The sample mean of each indicator; Construction process data correlation coefficient matrix Correlation coefficient and obtain its eigenvalues. eigenvectors and variance contribution rate : Calculate the cumulative contribution rate of m components. And retain the key components when they accumulate to 90%; The information on the indicative gaseous components of aquatic product quality, including type, concentration, and retention time (RT), is analyzed using score maps and stored in a database.

2. The microenvironment gas composition monitoring system for aquatic product cold storage according to claim 1, characterized in that, The MEMS gas detection module includes a MEMS front-end device and a MEMS main device connected to the MEMS front-end device. The MEMS front-end device includes a pH sensor and a micro pre-concentration injection device. The pH sensor is used to detect the pH value, and the micro pre-concentration injection device is used to enrich the gas components in the cold storage. After the detected pH reaches a preset threshold, the micro pre-concentration injection device is activated to realize subsequent monitoring of the gas environment. The MEMS main device includes a carrier gas module, a micro-chromatographic column module, and a micro-sensor module. The carrier gas module is used to enrich the gas components in the cold storage by the pre-concentration injection device and pump them into the micro-chromatographic column module. The micro-chromatographic column module is used to adsorb and separate the gas components. The micro-sensor module is used to analyze the separated gas components and represent the gas components using electrical signals.

3. The microenvironment gas composition monitoring system for aquatic product cold storage according to claim 2, characterized in that, The micro-chromatographic column module includes a gas inlet, two independent square chromatographic channels, one non-chromatographic channel, and a gas outlet. The chromatographic channels are filled with polar and non-polar stationary phases. The non-chromatographic channel is not filled with stationary phase, and the gas components enter the micro-sensor module directly without chromatographic separation after passing through the non-chromatographic channel.

4. The microenvironment gas composition monitoring system for aquatic product cold storage according to claim 1, characterized in that, The analytical prediction model includes: In the formula: C t C0 represents the initial content of the physicochemical indicators of aquatic products after storage time t; k represents the constant of the rate of quality decline; t represents the storage time; a and b are constants. f ( x ) represents the quality change indicators: a0, a1, ... a n They are constants, x Influencing factors: oxygen concentration, carbon dioxide concentration, nitrogen concentration, and temperature of the microenvironment; T represents absolute temperature; k1 represents the rate constant; R represents the gas constant; E a Indicates the activation energy of the reaction; Finally, a coupled model of the indicative gas components and physicochemical indicators of changes in the microenvironment of cold storage was obtained: 。 5. A method for monitoring the gas composition of the microenvironment in a cold storage for aquatic products, employing the gas composition monitoring system for the microenvironment of a cold storage for aquatic products as described in any one of claims 1-4, characterized in that, Includes the following steps: The MEMS gas detection module monitors the gas component signals of the microenvironment in the cold storage of aquatic products, including the pH sensor being activated to collect pH data. The temperature monitoring and location module monitors the temperature and location information of aquatic products in real time during the storage process. Determine whether the pH data monitored by the pH sensor has reached the threshold: if it has, start the micro pre-concentration injection device to pump the carrier gas into the micro chromatography column module, and the micro chromatography column module adsorbs and separates each gas component. The miniature sensor module analyzes the separated gas components and represents the gas components using weak electrical analog signals. The information aggregation and adaptive analysis and processing module analyzes and judges the monitored gas component signals, converts the gas component time and intensity signals monitored by the micro-sensor module into the actual types and concentrations of each gas, and establishes a database of gas components that are indicative of aquatic product quality. At the same time, it constructs an analysis and prediction model by combining temperature information and location information with gas concentration thresholds to regulate the microenvironment of the cold storage. The analysis, prediction and control module stores multiple preset programs and obtains the trend of gas environment changes based on the analysis and prediction model. It also controls the environmental parameters of the cold storage microenvironment according to different levels of gas concentration thresholds. The early warning and control module notifies users and automatically adjusts relevant parameters in the cold storage. The actual types, concentrations, and temperature data of each gas component, as well as alarm and early warning information, are all displayed in the information interaction module.

6. The method for monitoring the gas composition of the microenvironment in a cold storage for aquatic products according to claim 5, characterized in that, When the gas concentration threshold obtained after processing the collected gas component information and temperature environment information by the analysis, prediction, and control module reaches the preset gas concentration, relevant control methods are proposed according to different gas concentration threshold levels. These control methods include: (1) Determine the parameters of the controlled atmosphere equipment, turn on the controlled atmosphere equipment and adjust the concentrations of CO2, O2 and N2; (2) Determine the parameters of the refrigeration equipment, turn on the refrigeration equipment, and adjust the micro-environment temperature; Once all parameters reach their preset values, the equipment will stop working and automatically shut down.

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