阅读说明：本技术 一种检测猪肉新鲜度的装置和方法 (Device and method for detecting freshness of pork ) 是由 范东雨 李洁昆 蔡亦梅 高静 张瑜 任鲁风 于 2018-09-25 设计创作，主要内容包括：本发明公开了一种基于电子鼻技术的猪肉肉质新鲜度检测装置及方法,实现了检测时间短,操作简单,且不受检测环境局限方便便携的功能和特点。本发明的检测装置包括气体采样入口,气体分析腔体,气体采样出口,气流辅助单元,气体成分敏感单元,嵌入式控制单元。被检测的猪肉样品中挥发出的气体经采样入口进入,在气体分析腔内与气体敏感单元发生反应,控制单元分通过分析气体敏感单元的信号检测判读猪肉肉质新鲜度。本发明舍弃了常见电子鼻技术中检测前前净化空气的步骤和装置,直接检测,快速得出结果。本发明可广泛应用于猪肉肉质新鲜度的现场检测场合。(The invention discloses a device and a method for detecting pork freshness based on an electronic nose technology, which realize the functions and characteristics of short detection time, simple operation, no limitation of detection environment, convenience and portability. The detection device comprises a gas sampling inlet, a gas analysis cavity, a gas sampling outlet, an airflow auxiliary unit, a gas component sensitive unit and an embedded control unit. The gas volatilized from the pork sample to be detected enters through the sampling inlet and reacts with the gas sensitive unit in the gas analysis cavity, and the control unit analyzes the signal detection of the gas sensitive unit to judge the meat freshness of the pork. The invention abandons the steps and devices for purifying air before detection in the common electronic nose technology, and directly detects to obtain the result quickly. The invention can be widely applied to the field detection occasion of pork freshness.)

1. The utility model provides a quick portable detection pork meat new freshness's device which characterized in that: the gas analysis device comprises a gas sampling inlet, a gas analysis cavity, a gas sampling outlet, an airflow auxiliary unit, a gas component sensitive unit and an embedded control unit;

the gas sampling inlet and the gas sampling outlet are respectively positioned at two ends of the gas analysis cavity, and the gas composition sensitive unit is positioned in the gas analysis cavity and is close to the gas sampling inlet.

2. The device for rapidly and conveniently detecting meat freshness of pork according to claim 1, wherein the gas sampling inlet is located at the front end of the gas analysis cavity and is blocked at the front end of the gas analysis cavity in the form of through holes, and the through holes have a shape comprising a grid shape, a honeycomb shape or a transverse grid shape.

3. The device for rapidly and conveniently detecting meat freshness of pork according to claim 1, wherein the gas sampling outlet is located at the end of the gas analysis cavity and is blocked at the end of the gas analysis cavity in the form of through holes, and the shape of the through holes comprises a grid, honeycomb or cross grid form.

4. The device for rapidly and conveniently detecting meat freshness of pork according to claim 1, wherein the airflow auxiliary unit is located near the gas sampling outlet and comprises a fan or an air pump, and the auxiliary airflow flows in from the gas sampling inlet, flows through the gas analysis cavity and then flows out from the gas sampling outlet.

5. The device for rapidly and conveniently detecting the meat freshness of pork according to claim 1, wherein the gas component sensitive unit is composed of a series of gas sensors, and comprises one or more of an electrochemical hydrogen sulfide sensor, an electrochemical ammonia gas sensor, a semiconductor type VOC sensor, a semiconductor type ammonia sensor, a semiconductor type amine sensor, a semiconductor type ethanol sensor and a semiconductor type nitrogen oxide sensor.

6. The device for rapidly and conveniently detecting the meat freshness of pork according to claim 1, wherein the embedded control unit comprises a signal processing unit for outputting signals of the gas component sensing unit, a core single chip microcomputer, a wireless communication unit and a battery power supply unit, wherein the battery power supply unit adopts a polymer lithium battery with higher capacity density.

7. The device for rapidly and conveniently detecting meat freshness of pork according to claim 6, wherein the signal processing unit comprises an independent operational amplifier and an independent analog-to-digital converter or an operational amplifier or an analog-to-digital converter integrated in a core single chip microcomputer.

8. A method for rapidly detecting pork quality is characterized by sequentially comprising the following steps:

based on quick portable detection pork meat new freshness's device, the first detection of start:

a) initialization: starting up the gas component sensitive unit, and preheating for not less than 5min at a position far away from the sample to be detected (the distance between the device and the sample is more than or equal to 50 cm);

b) and (3) starting detection: the gas sampling inlet of the device is inclined downwards by 45 degrees and is aligned with the sample, the gas sampling inlet is close to the sample (the distance is not more than 5 cm), the gas sampling outlet is inclined upwards, and the duration time is not more than 30 s;

c) and (4) finishing detection: the result is output and stored in the control unit;

non-startup first detection:

d) preparing and detecting: after the last test is finished, the device is far away from the tested sample (the distance between the device and the sample is more than or equal to 50 cm) for not less than 1 min;

e) and (3) starting detection: the gas sampling inlet of the device is inclined downwards by 45 degrees and is aligned with the sample, the gas sampling inlet is close to the sample (the distance is not more than 5 cm), the gas sampling outlet is inclined upwards, and the duration time is not more than 30 s;

f) and (4) finishing detection: the result is output and stored in the control unit.

Technical Field

The invention relates to a pork freshness detection technology based on an electronic nose technology, in particular to a quick, portable and field-applicable pork freshness detection technology.

Background

Pork is the meat food with the largest consumption in China at present, and the freshness detection of the pork is related to the healthy diet problem of most people. The traditional methods for detecting the freshness of the pork at present comprise sensory detection, physicochemical detection (the content of volatile basic nitrogen is the national meat freshness detection standard method) and microbial detection.

Sensory testing does not require instrumentation and advanced techniques, but the test results are completely dependent on the subjective judgment and experience of the tester. The physical and chemical detection and the microbial detection can accurately detect the freshness of the pork, but the two methods can detect the pork by mincing the pork under laboratory conditions and have destructive effect on meat.

Modern detection technology continuously adopts new technologies in various fields, such as near infrared spectrum technology, artificial olfaction detection technology, computer vision technology, ultrasonic technology and the like.

Although various relevant detection devices are available in the market at present, the systems are large or complex and do not have the condition of rapid field detection.

A detection instrument which takes an artificial olfaction detection technology as a detection means in the market is called an electronic nose, and a gas sensor array is adopted as a data acquisition medium to acquire gas components and content of gas volatilized from pork so as to judge the freshness of the pork. Mature products have appeared abroad, but the products still stay in the laboratory stage at home. Moreover, most devices are expensive, and the application and maintenance are complex, and the requirements of rapid field detection are not met.

Most of domestic electronic nose detection technologies mostly adopt purified air as a reference for avoiding influences around a detection environment, and are complex in operation and time-consuming.

Disclosure of Invention

Aiming at the characteristics of large volume, high detection cost, long time consumption, limited detection place and the like of the conventional pork freshness detection equipment, the invention provides the pork freshness detection device which can be used for rapidly detecting pork freshness on site at low cost, and the detection device is realized by the following technical scheme:

the utility model provides a quick portable detection pork meat new freshness's device, includes gaseous sampling entry, gaseous analysis cavity, gaseous sampling export, air current auxiliary unit, gaseous composition sensing unit, embedded control unit. The gas sampling inlet and the gas sampling outlet are respectively positioned at two ends of the gas analysis cavity, and the gas composition sensitive unit is positioned in the gas analysis cavity and is close to the gas sampling inlet.

In some embodiments, wherein the gas sampling inlet is located at the front end of the gas analysis chamber and is blocked at the front end of the gas analysis chamber by a grid of through holes of a shape comprising a grid, honeycomb or cross grid form.

In some embodiments, wherein the gas sampling outlet is located at an end of the gas analysis chamber and is blocked at the end of the gas analysis chamber by a grid of shaped through holes, the shape of the through holes comprises a grid, honeycomb or cross grid form.

In some embodiments, wherein the gas flow assisting unit is located near the gas sampling outlet, and comprises a fan or a gas pump, the assisting gas flow flows in from the gas sampling inlet, flows through the gas analysis chamber and then flows out from the gas sampling outlet.

In some embodiments, the gas composition sensitive unit is composed of a series of gas sensors, including one or a combination of electrochemical hydrogen sulfide sensor, electrochemical ammonia gas sensor, semiconductor type VOC sensor, semiconductor type ammonia sensor, semiconductor type amine sensor, semiconductor type ethanol sensor, and semiconductor type nitrogen oxide sensor.

In some embodiments, the embedded control unit comprises a signal processing unit for outputting signals from the gas composition sensing unit, a core single chip microcomputer, a wireless communication unit and a battery power supply unit, wherein the battery power supply adopts a polymer lithium battery with higher capacity density.

In some embodiments, the signal processing unit comprises a separate operational amplifier and a separate analog-to-digital converter or an operational amplifier or an analog-to-digital converter integrated inside the core single chip.

A method for rapidly detecting pork quality sequentially comprises the following steps:

based on quick portable detection pork meat new freshness's device, the first detection of start:

a) initialization: starting up the gas component sensitive unit, and preheating for not less than 5min at a position far away from the sample to be detected (the distance between the device and the sample is more than or equal to 50 cm);

b) and (3) starting detection: the gas sampling inlet of the device is inclined downwards by 45 degrees and is aligned with the sample, the gas sampling inlet is close to the sample (the distance is not more than 5 cm), the gas sampling outlet is inclined upwards, and the duration time is not more than 30 s;

c) and (4) finishing detection: the result is output and stored in the control unit.

Starting up for non-first detection:

d) preparing and detecting: after the last test is finished, the device is far away from the tested sample (the distance between the device and the sample is more than or equal to 50 cm) for not less than 1 min;

e) and (3) starting detection: the gas sampling inlet of the device is inclined downwards by 45 degrees and is aligned with the sample, the gas sampling inlet is close to the sample (the distance is not more than 5 cm), the gas sampling outlet is inclined upwards, and the duration time is not more than 30 s;

f) and (4) finishing detection: the result is output and stored in the control unit.

The invention has the beneficial effects that:

1. the gas circuit design of the equipment is greatly simplified, the volume of the detection equipment is reduced, and the detection equipment is separated from the mains supply for power supply, so that the field detection and carrying are convenient;

2. the method of measuring and determining the base line is adopted, the field detection interference is removed, the detection steps are simplified, and the detection time is greatly shortened.

Drawings

FIG. 1 is a schematic cross-sectional view of the inventive apparatus;

FIG. 2 is a front view of the internal PCB circuit board of the inventive device;

FIG. 3 is a schematic of the housing of the inventive apparatus;

fig. 4 is a partial view of the gas sampling port of the inventive apparatus.

Detailed Description

The invention is described in further detail below with reference to the accompanying drawings:

referring to fig. 1, 100 is a cross-sectional view of the device, wherein 102 is a housing portion of the device, the housing is formed by a mold injection molding process, the material is selected from general engineering plastics, such as PP, PC, ABS, etc., and ABS is preferred as the main component of the housing for cost and performance reasons. Reference numeral 101 denotes a sample gas collecting device, which is installed at a gas sampling inlet 107 of the system device in a bell-mouthed shape design to assist in collecting the sample gas. The manufacturing and processing technology also selects a mould injection molding technology, and ABS is also preferably selected as the material. The gas sensor array 106 is located near the gas sampling inlet 107 to most directly detect the collected sample gas. The gas sensor array consists of two types of gas sensors, one of which is TGS2603 (1061 in fig. 2) of the company fergaro, japan, which is mainly sensitive to amine-based gases. The second is mics-6814 (1062 in fig. 2) of SGX corporation, uk, which uses MEMS technology to package VOC sensors, ammonia sensors and nitrogen oxide sensors in a 5 × 7 × 1.5mm metal device, and has the characteristics of small volume and low heating power consumption. The two gas sensors both adopt the technology of reducing the power consumption to the maximum extent and are suitable for battery power supply occasions such as portable equipment. The battery device 103 is mounted and fixed on the back of the PCB 105, preferably a polymer lithium battery with high capacity density, and the capacity is more than 1200mAh, preferably 1500mAh, which ensures that the device can independently work for more than 8h after being fully charged at one time. The fan 104 functions to assist the flow of the gas, the fan 104 is turned on, and the auxiliary gas flows in from the gas sampling inlet 107, passes through the sensor array 106, passes through the temperature and humidity sensor 109, passes through the entire chamber, and finally flows out from the gas sampling outlet 108. The fan 104 is selected to be a small volume and low power consumption model, preferably UF3F3-500 from SUNON, with a volume size of 15 × 3mm and a power consumption of only 0.1W. The device can also collect gas by adopting a natural diffusion mode, namely, the fan 104 is not started during detection, so that the detected gas enters from the gas sampling inlet 107 in a natural diffusion mode, flows through the gas sensor array 106 and the temperature and humidity sensor 109, passes through the whole cavity and finally flows out from the gas sampling outlet 108, but the detection error of the mode is larger, so that the device preferably adopts a fan to assist the gas flow scheme.

Fig. 2 is a front view of the PCB 105 installed inside the device, in which the gas sensors 1061 and 1062 are arranged in parallel near the gas sampling inlet 107, the temperature and humidity sensor 109 is arranged behind the sensor array, and a slot 205 is formed around the temperature and humidity sensor, wherein the width of the slot 205 is 1mm, so as to prevent the heat generated by the heater of the gas sensor array from affecting the temperature measurement of the temperature and humidity sensor 109 through the PCB. The temperature/humidity sensor 109 compensates the detected signal of the gas sensor, and because the detected signal varies with the temperature/humidity due to the characteristics of the gas sensor, a temperature/humidity compensation algorithm needs to be added to improve the measurement accuracy of the gas sensor. The core controller 203 is responsible for signal processing and related control in the detection process, and is a core processing unit of the device. The unit is provided with an AD converter and a signal filter. The sealing rubber ring 202 is located between the PCB 105 and the housing 102, and is used for filling a gap between the periphery of the PCB 105 and the housing 102, so that a sealed detection cavity is formed, and the correctness of the flow direction of the sampled gas is ensured.

In fig. 3, a display screen 301 and keys 302 are used for human-computer interaction of the device, and a gas sampling outlet 303 is positioned at the tail end of the device and adopts cross-grid-shaped through holes to ensure normal outflow of sampling gas. Meanwhile, the gas sampling inlet 401 is arranged at the front end of the device in fig. 4, and is also preferably provided with cross grid-shaped through holes to ensure the normal inflow of the sampling gas.