Since the outbreak of New Crown Pneumonia has entered the normalized prevention and control phase, "cold chain food" has become the focus of public opinion due to its repeated positive detection of New Crown Virus. Many people naturally associate it with the New Crown Virus, and panic at the mention of cold chain. Cold-chained foods have been targeted and criticized for a while.

It is true that cold-chained foods are highly correlated with the new coronavirus,cold chain but this does not mean that we should reject all cold-chained foods. In fact, it is unnecessary and unrealistic.

The cold chain has long been inextricably linked to our lives. So what is the cold chain?

Cold chain refers to a special supply chain system in which certain products are processed, stored, transported, distributed and retailed, and used in a specific low-temperature environment that is always necessary to ensure the safety of the product.

The scope of application of this "chain" is very wide, including primary agricultural products (such as vegetables, fruits and vegetables, meat, poultry, eggs, milk, aquatic products, etc.), processed food (such as frozen food, ice cream, dairy products, chocolate,cold warehouse fast food ingredients, etc.) and special commodities (such as drugs, vaccines, etc.). Of course, it is the cold chain food that has the closest intersection with our lives.

The storage period of food transported by cold chain logistics is one to several times longer than that of ordinary refrigerated food. By controlling the temperature circulation link, it can effectively reduce the growth of microorganisms and corrosion of food; at the same time, in the process of cold chain logistics, it can inhibit the respiratory state of fruits and vegetables after picking by means of gas conditioning, so as to achieve the effect of preservation of fruits and vegetables. It can be seen that cold chain logistics plays an important role in improving our quality of life.

Cold chain logistics consists of raw material acquisition and cooling, refrigerated processing, refrigerated storage, refrigerated transportation and distribution, refrigerated sales, and one of its core components is "temperature-controlled heat preservation", which includes constant temperature and humidity cold storage and air-conditioned cold storage with precise requirements for humidity and temperature of stored items. "Air-conditioning cold storage".

The so-called air-conditioning preservation, is the oxygen concentration in the air from 21% down to 3% -5%, on the basis of cold storage, add a set of air-conditioning system, the use of temperature and control of oxygen content of the two aspects of the common role, to achieve the respiratory state of fruits and vegetables after harvest.

And in the cold chain logistics process of food handling operations is very important and difficult step. Refrigerated, frozen goods to unloading vehicles and unloading warehouse sealing treatment, to ensure that unloading during the food temperature rise control in the permissible range, and unloading operations interruptions, to instantly close the door of the transport equipment compartments, to maintain the normal operation of the refrigeration system.

Under the precise cooperation of the above links, cold chain food can reach consumers quickly, safely and smoothly.

Then, why the cold chain food will become the "lurking place" of the new crown virus? This is because the virus will not be frozen to death in a low-temperature environment. Generally speaking, the lower the temperature, the longer the virus survives. The low temperature environment created by the cold chain provides a good space for the virus to survive. Typically, viruses can survive for months at -20°C. Even with normal cold chain transportation, viruses can survive for several weeks. In the case of contaminated items (including foodstuffs or outer packaging) in areas of high incidence of new crown outbreaks, cold chain transportation can carry the virus to non-infected areas, thus causing contact transmission and triggering new outbreaks.

In this view, can cold chain food still be eaten? On this question, experts explained that no neocoronavirus infections have been detected as a result of direct consumption of cold-chained foods. New Coronavirus is mainly transmitted through respiratory droplets and close human-to-human contact, and the possibility of infection through the digestive tract is very low. From the epidemiological traceability analysis, the infected people are high-risk groups who repeatedly come into contact with the outer packaging of imported cold-chained food in specific environments, such as porters.

Nowadays, cold chain logistics has been developing continuously towards intelligence, specialization, diversification, informationization, standardization and greening. There is no need to demonize the cold chain because of the sporadic emergence of disseminated cases. The establishment of standardized and orderly cold chain quarantine safety norms, the use of information technology to strengthen traceability and monitoring management, strengthening the disinfection and protection of chain staff, and improving the personal hygiene of citizens are the higher requirements put forward by the logistics era.