New requirements for food safety testing released

The Ministry of Agriculture and the National Health and Family Planning Commission jointly issued the National Food Safety Standard "Maximum Residue Limits of Pesticides in Foods" (GB2763-2014), which was formally implemented on August 1st. This new standard "provides 387 pesticides in 284 species (classes). ) The 3 650 limited indicators in foods have been increased by 65 pesticides, 43 foods, and 1357 limit indicators compared to the current standards. They are considered to be "substantially covering the types of food commonly used in agricultural production and the type of food the public regularly consumes." ".

Food safety rapid detection technology has become a bottleneck. "People are the center of the country, food is the priority, and food is safe." Safeguarding food safety has become the basis for ensuring human life and health, and has become the basis for improving economic performance and human quality. The new standard “Maximum Residue Limits for Pesticides in Food” (the National Standard for the Most Severe Pesticide Residues in History) (GB2763-2014) is just a national food safety standard published by the National Health and Family Planning Commission since the implementation of the Food Safety Law. One of the criteria in thousands of safety indicators).

The matching required for the implementation of strict standards is the rapid detection technology for food safety and the need for new detection technologies such as species identification. In the traditional food safety inspection process, it generally requires on-site sampling and pretreatment of the analytes. , instrument detection, data processing and many other steps (follow-up several steps are often carried out in the laboratory), so the detection process is cumbersome, long analysis time, often unable to meet the needs of the scene of rapid law enforcement. In other words, most of the tests are carried out by food safety supervisors collecting samples, and professional technicians using precision instruments in the laboratory to perform inspections based on the relevant food safety indicators. (Although there are currently rapid testing car developments, they are expensive. It cannot be widely promoted by the food regulatory authorities - especially for supermarkets, farmers' markets, catering companies, etc.)

Taking metformin pesticide residues in foods for example, the current detection methods include gas chromatography (GC), high performance liquid chromatography (HPLC), spectrophotometer, chemiluminescence, enzyme inhibition, capillary electrophoresis (CE), etc. However, these methods have the limitations of complex equipment, complicated sample preprocessing and measurement operations. Moreover, these testing equipments have high costs, high testing costs, and high requirements for inspectors. They are not suitable for large-scale sample screening, and thus cannot be used on a large scale in grassroots food inspection departments, not to mention supermarkets, farmers' markets, Catering companies, or consumers.

Contradictions between portability, diversity and stability

The reason is that the existing food safety testing instruments are often complicated in structure and inconvenient to carry. From the basic principle point of view, food detection is generally converted to electricity, light and other signals through the signal generated after the food sample to be detected reacts with the biometric element, and then amplified, output and analyzed by the instrument. The principle of smart devices represented by Baidu Chopsticks is roughly the same - however, its combination with mobile devices, etc., makes it possible to incorporate big data and cloud computing features in data integration and analysis (such as food spectrum databases).

However, in the implementation of specific food safety standards, ensuring the scientificity and rigor of the tested equipment is a prerequisite for the enforcement of food safety. In terms of current technology, the food safety rapid testing equipment has not yet achieved the ideal module. And miniaturization to meet the requirements of high stability and portability at the same time.

In fact, not only in the area of ​​food testing, but also in many fields such as biomedical analysis, disease diagnosis, environmental monitoring, and drug safety, they face similar challenges - the development of miniaturization, integration, and portability of inspection and quarantine analysis tools and equipment. A set of simple, fast, high-sensitivity, universally applicable methods have become common needs.

The integration of biotechnology and various technologies is among these. Biosensors, including electrochemical sensors, optical sensors, conductance sensors, piezoelectric sensors, etc., are the key to the detection of biosensors. For example, strains such as Bifidobacterium breve that are not susceptible to bacterial contamination and susceptible to methamidophos pesticides are screened, and signals can be converted into electrical and optical signals and amplified and analyzed to improve detection. effectiveness.

Development of non-laboratory, wide-range rapid detection technologies In addition, the development of miniaturized, integrated, and portable inspection and quarantine equipment requires a modular sensor as a support and foundation—although current automated biochemical analyzers are available. Some or all of these steps, such as sampling, adding reagents, mixing, heat preservation, colorimetry, results calculation and reporting, are completed by automation, but they still have the limitations of large size, high price, complicated operation, and training by professionals.

In addition, food testing mainly includes pesticide residues, veterinary drug residues, detection of illegal additives, microbial detection, species detection (animal and plant-derived components), genetic testing, and other aspects. The development of biosensors capable of simultaneous determination of multiple indicators is also a long way to go. . For example, the large-scale use of chemical pesticides and the increase of food and water pollution pathways, the number of objects to be detected is also increasing, and the degree of integration required is increasing.

It can be seen that the development of miniaturization, integration, and portability of food testing equipment is still relatively difficult, but in the face of large-scale, rapid outbreaks of food safety issues on the market, it can meet national technical standards and food safety inspection benchmarks. It is imperative to implement non-laboratory and large-scale rapid detection technology for food production, storage, and sales.

In the face of this reality, while strengthening the development of rapid detection reagents and food safety detection biosensors, the standardization issues such as the compatibility and matching of the communication interface for data uploading and receiving of food safety detectors with various external devices are also very important. At the same time, in order to convert biochemical information into signals such as electricity and light, and then through instrument amplification, output, and analysis, how to optimize signal and noise in real time to reduce noise, and achieve different harms for various types of objects to be detected The integration of material detection (currently, the wavelength of the used light source is different in the detection process of different harmful substances) is very important.