Portable fried oil acid value real-time monitoring device based on electronic nose

Abstract

The invention relates to the field of oil acid value monitoring, in particular to a portable fried oil acid value real-time monitoring device based on an electronic nose. A portable real-time monitoring device for the acid value of fried oil based on an electronic nose comprises a display screen used for displaying the acid value, a gas path system, a gas pump, a smell sensor module used for detecting volatile organic compounds volatilized by the fried oil, and an MCU processor. The device has the advantages that the device does not need to be immersed in oil for detection, and acid value detection is achieved by detecting gas of frying oil. The portable device for oil acid value detection based on gas is provided, the oil change time is conveniently controlled, the safety problem caused by late oil change is avoided, the use safety of frying oil is improved, waste caused by early oil change is avoided, and the production cost of an enterprise is reduced.

Description

Technical Field

[0001] The present invention relates to the field of oleic acid value monitoring, and in particular to a portable real-time monitoring device for the oleic acid value of frying oil based on an electronic nose. Background Art

[0002] At present, the quality monitoring of frying oil mainly adopts traditional chemical detection methods and laboratory instrument detection. The traditional chemical detection method takes 4 - 6 hours for a single detection and requires professional personnel to complete it in the laboratory. Some enterprises use the test paper colorimetry method for preliminary screening, but the accuracy is low and the key indicators cannot be quantified. Laboratory instrument detection uses equipment such as GC (gas chromatography) and high-performance liquid chromatography (HPLC) to accurately analyze the quality of frying oil, but the equipment is expensive and only suitable for third-party testing institutions.

[0003] The main defects are as follows: 1) Low detection efficiency and poor timeliness: The traditional chemical method takes 4 - 6 hours, and the accuracy of the test paper method is insufficient, resulting in a "detection window period" for oil products and being unable to give a real-time warning of the risk of excessive acid value.

[0004] 2) Equipment portability and cost issues; Laboratory instruments are expensive and bulky, and commercial electronic noses are large in volume and weigh > 10 kg, making it difficult to deploy in places such as kitchens and catering stores.

[0005] 3) Lack of intelligence and decision support: Existing electronic noses only achieve data collection and do not integrate intelligent algorithms. It is necessary to rely on manual experience to judge the timing of oil change, resulting in more than 20% of oil products being wasted or having safety risks due to premature abandonment or overuse.

[0006] 4) Data isolation: Existing equipment lacks wireless communication modules such as Wi-Fi / Bluetooth, and the detection data cannot be uploaded to the management platform in real time, making it difficult to achieve multi-terminal collaboration. Summary of the Invention

[0007] The purpose of the present invention is to provide a portable real-time monitoring device for the oleic acid value of frying oil based on an electronic nose to solve the problems raised in the above background art.

[0008] To achieve the above purpose, the present invention provides the following technical solutions: A portable real-time monitoring device for the oleic acid value of frying oil based on an electronic nose includes: a display screen for displaying the acid value, an air circuit system, a gas pump, an odor sensor module for detecting volatile organic compounds volatilized from frying oil, and an MCU processor; One end of the air circuit system is provided with a detection probe with an air inlet; the gas pump inhales the gas above the oil sample to be tested through the air inlet of the detection probe and transmits it to the odor sensor module through the air circuit system; The odor sensor module consists of a metal oxide gas sensor array; the metal oxide gas sensor array detects volatile organic compounds and generates a resistance change signal; the MCU processor converts the resistance change signal of the metal oxide gas sensor array into an acid value and displays it through a display screen.

[0009] As a further solution of the present invention: a portable frying oil acid value real-time monitoring device based on an electronic nose further includes: a housing; a gas pump, an odor sensor module, and an MCU processor are arranged inside the housing.

[0010] As a further solution of the present invention: a portable frying oil acid value real-time monitoring device based on an electronic nose further includes: a main control board; the MCU processor is arranged on the main control board; the main control board is provided with a signal amplification circuit for amplifying the resistance change signal of the metal oxide gas sensor array; the signal amplification circuit amplifies the resistance change signal of the metal oxide gas sensor array and transmits it to the MCU processor; the MCU processor converts the resistance change signal of the metal oxide gas sensor array amplified by the signal amplification circuit into an acid value.

[0011] As a further solution of the present invention: a Bluetooth module is arranged on the main control board or the MCU processor uses a chip with Bluetooth function.

[0012] As a further solution of the present invention: a portable frying oil acid value real-time monitoring device based on an electronic nose further includes: a battery system; the battery system supplies power to the gas pump, the odor sensor module, and the MCU processor; the battery system is located inside the housing.

[0013] As a further solution of the present invention: the metal oxide gas sensor array is installed inside the detection probe.

[0014] As a further solution of the present invention: a stainless steel filter screen is arranged at the air inlet of the detection probe.

[0015] As a further solution of the present invention: the sensors of the metal oxide gas sensor array include TGS2602 gas sensor, TGS822 gas sensor, TGS813 gas sensor, and TGS825 gas sensor.

[0016] As a further solution of the present invention: an integrated flow sensor for detecting the gas flow on the gas path system and a solenoid valve for controlling the gas flow in the gas path system are arranged on the gas path system; the integrated flow sensor controls the solenoid valve based on the detected gas flow.

[0017] As a further solution of the present invention: the gas path system is provided with two-stage filtration, the first stage of filtration is a PTFE hydrophobic filter membrane, and the second stage of filtration is an activated carbon layer.

[0018] The advantages of the present invention are as follows: It is not necessary to immerse in oil for detection, and the acid value detection is realized by detecting the gas of frying oil. A portable device for detecting the acid value of frying oil based on gas is provided, which is convenient for controlling the timing of oil change, avoiding safety problems caused by late oil change, improving the safety of using frying oil, avoiding waste caused by early oil change, and reducing the production cost of enterprises.

[0019] It can detect the acid value of frying oil on-site without sampling for laboratory detection. It has higher efficiency compared with the traditional chemical detection method. The device is portable and convenient to deploy in places such as kitchens and catering stores.

[0020] It can monitor the acid value of frying oil, automatically judge the current acid value state, so as to guide the oil change, avoiding the need for manual experience to judge the oil change timing, resulting in waste or safety risks caused by more than 20% of the oil being prematurely discarded or overused.

[0021] Data can be transmitted through Bluetooth or WIFI modules and uploaded to the management platform for convenient management.

[0022] Other features and advantages of the present invention will be disclosed in detail in the following specific embodiments and drawings. Description of the Drawings

[0023] Figure 1 is a schematic diagram of a portable real-time monitoring device for the acid value of frying oil based on an electronic nose of the present invention; Figure 2 is Figure 1 a perspective view of the internal structure of the portable real-time monitoring device for the acid value of frying oil based on an electronic nose in Figure 3 is Figure 1 a perspective view of the internal structure of the detection probe of the portable real-time monitoring device for the acid value of frying oil based on an electronic nose in

[0024] List of reference numerals: Portable real-time monitoring device 100 for the acid value of frying oil based on an electronic nose, display screen 1, gas path system 2, gas pump 3, odor sensor module 4, detection probe 5, stainless steel filter screen 51, battery system 6, housing 7, main control board 8. Detailed Description of the Invention

[0025] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0026] As Figures 1 to 3As shown in the figure, a portable real-time monitoring device 100 for the acid value of frying oil based on an electronic nose includes: a display screen 1 for displaying the acid value, a gas path system 2, a gas pump 3, an odor sensor module 4 for detecting volatile organic compounds volatilized from frying oil, and an MCU processor.

[0027] One end of the gas path system 2 is provided with a detection probe 5 with an air inlet. The gas pump 3 sucks the gas above the oil sample to be measured through the air inlet of the detection probe 5 and transmits it to the odor sensor module 4 through the gas path system 2.

[0028] The odor sensor module 4 is composed of a metal oxide (MOX) sensor array. The metal oxide gas sensor array detects the change in resistance generated by volatile organic compounds. The MCU processor converts the resistance change signal of the metal oxide gas sensor array into an acid value and displays it through the display screen 1.

[0029] As a preferred embodiment, the display screen 1 is a touch-type liquid crystal screen. The display screen 1 can display the detection curve and the device status information. The gas pump 3 is a micro diaphragm pump, which actively sucks the gas to be measured into the gas path system 2.

[0030] As a specific embodiment, a portable real-time monitoring device 100 for the acid value of frying oil based on an electronic nose further includes: a housing 7. The gas pump 3, the odor sensor module 4 and the MCU processor are arranged in the housing 7. The display screen 1 is installed on the housing 7. The housing 7 is provided with a main power switch to control the start and stop of the device. Physical buttons can also be set on the housing 7 as needed for control. The buttons include key caps and micro switches. Pressing the key cap triggers the micro switch. The key cap is made of silica gel, and symbols such as "+" and "-" can be engraved on the surface. The micro switch is designed as a surface-mounted type. The button includes at least one control button. The control logic of the control button is: short press (≤1 second), switch the acid value unit of the display screen 1; long press (≥3 seconds) to enter the threshold setting mode; double click to start the sensor calibration program, and the display screen 1 shows "calibrating".

[0031] Multi-functional trigger logic: short press (≤1 second): switch the acid value unit of the display screen; long press (≥3 seconds) to enter the threshold setting mode; double click to start the sensor calibration program, and the screen shows "calibrating".

[0032] As a specific implementation, a portable real-time monitoring device 100 for the acid value of frying oil based on an electronic nose further includes: a main control board 8. The MCU processor is arranged on the main control board 8. The main control board 8 is provided with a signal amplification circuit for amplifying the resistance change signal of the metal oxide gas sensor array. The signal amplification circuit amplifies the resistance change signal of the metal oxide gas sensor array and then transmits it to the MCU processor. The MCU processor converts the amplified resistance change signal of the metal oxide gas sensor array into an acid value.

[0033] As a specific implementation, a Bluetooth module is arranged on the main control board 8 or the MCU processor uses a chip with Bluetooth function. As a preferred implementation, the MCU processor uses an STM32F407 chip, with a built-in 12-bit ADC module and a sampling frequency of 1 kHz. The signal amplification circuit uses an AD623 amplification circuit. The main control board 8 integrates a temperature and humidity sensor to compensate for environmental interference in real time. As a specific implementation, a WIFI module can also be set up for data transmission.

[0034] As a specific implementation, a portable real-time monitoring device 100 for the acid value of frying oil based on an electronic nose further includes: a battery system 6. The battery system 6 supplies power to the gas pump 3, the odor sensor module 4, and the MCU processor. The battery system 6 is located inside the housing 7. The battery system 6 uses a rechargeable lithium battery and supports continuous operation for more than 10 hours.

[0035] A portable real-time monitoring device 100 for the acid value of frying oil based on an electronic nose further includes: a speaker. The speaker is used to play detection information, such as emitting a prompt sound like "The oil needs to be replaced when the acid value exceeds the standard".

[0036] As a specific implementation, the metal oxide (MOX) gas sensor array is installed in the detection probe 5.

[0037] As a specific implementation, a stainless steel filter screen 51 is arranged at the air inlet of the detection probe 5. The stainless steel filter screen 51 is used to intercept large particle oil mist. The air inlet of the detection probe 5 is surrounded by a conical polycarbonate with an inner diameter of 5 mm. A gas test chamber is formed inside the detection probe 5. The gas test chamber is a cylindrical aluminum alloy cavity with a diameter of 30 mm, and the inner wall is coated with a polytetrafluoroethylene (PTFE) coating to reduce gas adhesion. A flow guiding partition is arranged in the center of the cavity to evenly distribute the air flow to the surrounding sensor areas.

[0038] The metal oxide gas sensor array consists of multiple gas sensors. Specifically, multiple gas sensors are distributed around the gas test chamber. The gas sensors are fixed through card slots. The surface of the sensors is covered with an oil-repellent nano-coating to prevent oil adhesion. The sensors of the metal oxide gas sensor array include TGS2602 gas sensor, TGS822 gas sensor, TGS813 gas sensor, and TGS825 gas sensor. The signal transmission line uses a flexible FPC cable. One end is welded to the sensor pin, and the other end is connected to the wiring port. The outer layer of the cable is wrapped with a high-temperature resistant silica gel sheath to prevent signal interference. The signal transmission line can be independent of the gas path system 2 or integrated into the parts forming the gas flow channel of the gas path system 2. For example, a hose forms the gas flow channel and the signal transmission line is wrapped in the wall of the hose. The hose can be set with a quick-release snap structure for convenient plugging and unplugging, and is sealed and connected through an O-ring. The signal transmission line can also be correspondingly provided with plug-in terminals. The hose can also reduce the vibration transmission of the gas pump 3.

[0039] As a specific implementation, the gas path system 2 is composed of multiple gas channels. It connects the air inlet to the odor sensor module 4, and the odor sensor module 4 to the gas discharge channel of the gas pump 3.

[0040] As a specific implementation, the gas path system 2 is provided with an integrated flow sensor for detecting the gas flow rate on the gas path system 2 and a solenoid valve for controlling the gas flow rate in the gas path system 2. The integrated flow sensor controls the solenoid valve based on the detected gas flow rate.

[0041] As a specific implementation, the gas path system 2 is provided with two-stage filtration. The first stage of filtration is a PTFE hydrophobic filter membrane, and the second stage of filtration is an activated carbon layer.

[0042] The flow rate range of the gas pump 3 is 0.1 - 1.0 L / min, the power ≤ 2 W, and the flow rate is dynamically adjusted through the PID algorithm.

[0043] Working principle: The gas pump 3 sucks the gas above the oil sample to be measured through the air inlet of the detection probe 5 and transmits it to the odor sensor module 4 through the gas path system 2. The metal oxide gas sensor array detects the change in resistance signal generated by volatile organic compounds. The MCU processor converts the resistance change signal of the metal oxide gas sensor array into an acid value and displays it through the display screen 1. The MCU processor uses an internal algorithm (PCA-LDA model) to convert the signal into an acid value. Real-time feedback: The acid value data is displayed on the display screen 1 in real time. If it exceeds the preset threshold (AV ≥ 4.5 mg / g), the speaker triggers an alarm, and at the same time, a warning icon flashes on the screen.

[0044] Workflow: Boot-up and preheating: Press the power switch, and the odor sensor module 4 automatically preheats for 30 seconds. The display screen 1 shows the "Ready" status. Sampling and detection: Place the inlet of the device close to the surface of the frying oil, start the gas pump 3, and complete gas collection and analysis within 10 seconds. Result output: The display screen 1 shows the real-time acid value and the historical trend graph. The user can switch the unit or save the data by pressing the button. Early warning linkage: If the detected value exceeds the standard, a voice alarm prompts to replace the oil, and at the same time, the data can be uploaded to the cloud platform through the wireless module.

[0045] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0046] In addition, it should be understood that although this specification is described according to the embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose, characterized in that, Comprising: A display screen (1) for displaying the acid value, an air path system (2), a gas pump (3), an odor sensor module (4) for detecting volatile organic compounds in the volatile matter of frying oil, and an MCU processor; One end of the air path system (2) is provided with a detection probe (5) with an air inlet; the gas pump (3) inhales the gas above the oil sample to be measured through the air inlet of the detection probe (5) and transmits it to the odor sensor module (4) through the air path system (2); The odor sensor module (4) is composed of a metal oxide gas sensor array; the metal oxide gas sensor array detects the resistance change signal generated by volatile organic compounds; the MCU processor converts the resistance change signal of the metal oxide gas sensor array into an acid value and displays it through the display screen (1).

2. The portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose according to claim 1, characterized in that The portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose further comprises: a housing (7); The gas pump (3), the odor sensor module (4) and the MCU processor are arranged in the housing (7).

3. The portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose according to claim 2, characterized in that The portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose further comprises: a main control board (8); The MCU processor is arranged on the main control board (8); The main control board (8) is provided with a signal amplification circuit for amplifying the resistance change signal of the metal oxide gas sensor array; The signal amplification circuit amplifies the resistance change signal of the metal oxide gas sensor array and transmits it to the MCU processor; the MCU processor converts the resistance change signal of the metal oxide gas sensor array amplified by the signal amplification circuit into an acid value.

4. The portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose according to claim 3, characterized in that A Bluetooth module is arranged on the main control board (8) or the MCU processor uses a chip with Bluetooth function.

5. The portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose according to claim 2, characterized in that The portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose further comprises: a battery system (6); The battery system (6) supplies power to the gas pump (3), the odor sensor module (4) and the MCU processor; the battery system (6) is located in the housing (7).

6. The portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose according to claim 1, characterized in that The metal oxide gas sensor array is installed in the detection probe (5).

7. The portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose according to claim 6, characterized in that A stainless steel filter screen (51) is provided at the air inlet of the detection probe (5).

8. A portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose according to claim 1, wherein the sensors of the metal oxide gas sensor array include a TGS2602 gas sensor, a TGS822 gas sensor, a TGS813 gas sensor, and a TGS825 gas sensor.

9. A portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose according to claim 1, wherein an integrated flow sensor for detecting the gas flow rate on the gas path system (2) and a solenoid valve for controlling the gas flow rate in the gas path system (2) are provided on the gas path system (2); the integrated flow sensor controls the solenoid valve based on the detected gas flow rate.

10. A portable real-time monitoring device (100) for the acid value of frying oil based on an electronic nose according to claim 1, wherein the gas path system (2) is provided with two-stage filtration, the first-stage filtration is a PTFE hydrophobic filter membrane, and the second-stage filtration is an activated carbon layer.

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