With the improvement of people’s living standards and purchasing power, higher requirements have been put on the variety, quantity, and quality of fresh fruits and vegetables. At the same time, the food safety of chemical synthetic preservatives used during storage has been questioned, making fruits, vegetables, and meat. The storage and preservation of foods such as foodstuffs are gradually moving towards a physics-based approach, and they are maintaining their natural quality, food safety, convenience, and low-energy storage. The physical preservation methods such as natural cold storage and wet and cold storage are gradually conforming to this development trend and have gradually been recognized and valued by people. First, the research status of wet cold preservation technology The wet cooling system is a new type of technology developed on the basis of mechanical ice and cold storage technology. It adopts the method of mechanical ice making to accumulate cold, obtaining low-temperature ice water through a mixed heat exchanger, allowing the ice water and the air inside the store to heat and mass transfer, and obtaining high-humidity air near the freezing point temperature to cool the fruits and vegetables. It can quickly cool the fruits and vegetables to the storage temperature and maintain it at this temperature. At the same time, combined with the synergy of ozone, the fruits and vegetables will be in a low temperature and high humidity environment without being harmed by mold. In some countries in Europe and America, the application of the cool-cold system in the preservation of fruits and vegetables was started as early as the mid-1970s. In 1978, the British agricultural engineer R. T. Lindsey, M. A. Neil et al.'s research results in this area laid the foundation for the application of this technology. At the end of 1994, British TES donated the key equipment of a small wet-cold system to the Food College of China Agricultural University. The first experimental cold storage was built in the school and a few years of experimental research was conducted. In 1997, the first building was built in Haikou City. Commercial cold storage was listed as a 97 Torch Program by the National Science and Technology Commission. In 2000, the first commercial cold storehouse in the north was built in Xianxian, Hebei Province, and was promoted as a technology development fund for machinery industry. It uses brine as a refrigerant to reduce the temperature in the store to below 0°C, and the relative humidity in the store can still be maintained. Stay around 95%. In the fresh-keeping test of winter jujube, both the good fruit rate and the storage quality were obviously better than other storage methods in the same period. Second, the main technical characteristics of wet cold preservation technology The supporting power of the compressor is reduced by 30%-50% compared with the conventional cold storage, and the refrigerant consumption is saved by 20%-30%. 2. Using low-cost low-cost power storage, storage and preservation costs can be reduced by 20%-30%. 3. Excluding humidification and defrosting operations, the temperature and humidity in the warehouse are stable. 4. Ozone can inhibit mold production, ethylene oxide, ethanol and residual pesticides, to achieve no effect of ethylene storage. 5. Pre-cooling with a high cold and humid airflow pressure difference, cooling the fruits and vegetables faster than the general air-cooled 4 times -6 times, and less water loss. 6. The product can be moved in and out of the library at any time for convenient circulation. Third, the development prospects of wet cold preservation technology Through the long-term storage of fruits and vegetables in the South and North, wet cold storage library can achieve the temperature inside the library is higher than 0 °C, relative humidity of 95% -100%, and below 0 °C In the environment, the relative humidity reaches 92%-95%, which greatly reduces the respiration intensity of fruits and vegetables, and the transpiration is inhibited, so as to maintain the original degree of freshness and wind of fruits and vegetables. In a high-humidity environment, ozone acts as a strong oxidant, not only killing and inhibiting the production of mold, but also oxidizing chemicals such as ethylene, ethanol, and pesticides. During storage, for fruits and vegetables that have a respiratory peak, ozone can oxidize exogenous ethylene, and can also permeate the internal oxidation of endogenous ethylene inside the fruit, truly achieving ethylene-free storage and prolonging the storage period of fruits and vegetables. The storage of winter jujube at storage temperature of -1 - -1.5 °C, the humidity up to 93%, combined with ozone inhibition, bactericidal effect, after 90 days of storage in winter jujube, the good fruit rate reached 90%, loss The water is only 1%-3%, keeping the red jujube color of winter jujube; no alcohol taste, keeping the best flavor of winter jujube. For the high moisture content, volatile fruits and vegetables, wet preservation technology has its unique preservation advantages. The investment in wet storage and cold storage is similar to that of ordinary cold storage, but the operating cost is lower than the latter. The research on wet-cold preservation technology and the development of wet-cold preservation warehouses are comprehensive projects of multidisciplinary disciplines such as light industry and agriculture. The author suggests that this technology should attract attention from the light industry, agriculture, and other departments, and jointly deepen the research work on this technology. The main ones are: Develop a temperature and humidity controller suitable for high humidity environments. 2. Practical development of ozone generators and ozone rapid detection equipment for high-humidity environments. Wet and cold preservation technology is the use of low-voltage electrical machinery cold storage, the use of differential pressure pre-cooling methods, can greatly increase the value of fresh agricultural products, coordination of seasonal fruits and vegetables and the annual supply and regional production and cross-regional consumption of contradictions, for the development of quality agriculture Has a positive role in promoting.