The preservation of fruits and vegetables is related to many factors, such as temperature, humidity and gas composition. The preservation packaging here mainly refers to how to keep fresh at room temperature. The fresh-keeping packaging of fruits and vegetables at room temperature is mainly composed of controlling gas composition and humidity, appropriate buffer packaging, and appropriate preservative. The preservation of fruits and vegetables is related to many factors, such as temperature, humidity and gas composition. The preservation packaging here mainly refers to how to keep fresh at room temperature. The fresh-keeping packaging of fruits and vegetables at room temperature is mainly composed of controlling gas composition and humidity, appropriate buffer packaging, and appropriate preservative. (1) Small package preservation method of fruits and vegetables. Small package of fruits and vegetables generally refers to a single package. There are two common preservation methods: ① Fresh film packaging. Fresh-keeping film is a kind of plastic film, which is almost impermeable to water, but oxygen and carbon dioxide are easy to pass through. When using this unique fresh-keeping film for single packaging of fruits and vegetables, the inside of the packaging bag is in a microclimate conducive to fresh-keeping of fruits and vegetables. Because this film has moderate permeability to oxygen and carbon dioxide, it can automatically adjust the concentration of oxygen and carbon dioxide in the packaging bag, so that its concentration can not only inhibit the respiration of fruits and vegetables, but also not damage the quality of fruits and vegetables. Generally, the oxygen concentration suitable for preservation is 1 ~ 6%, and the carbon dioxide concentration is 1 ~ 1%. Because this film is almost impermeable to water, the relative humidity in the bag increases, which can prevent the fruits and vegetables from drying and shrinking due to excessive evaporation of water. Commonly used preservation films include polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride and other films. ② Preservatives are used to keep fresh. Preservatives can delay the life activities of fruits and vegetables and keep them fresh. Preservatives are divided into solid and liquid. Small packages are multi-purpose liquid preservatives. When in use, the fruit is immersed in the dipping solution, and then taken out and dried, so that an edible ultra-thin protective film is formed on the surface of the fruit, which can block the pores on the surface of the peel, weaken the respiration and keep fresh. This method is generally used for fruits. (2) The outer packaging of fruits and vegetables, also called big packaging, is to put a certain number of fruits and vegetables in one package. Fresh-keeping containers keep fresh. Fresh-keeping container is a container with fresh-keeping performance. A layer of fresh-keeping film such as polyethylene can be sandwiched in corrugated paper and then made into cartons; Polyethylene coating can also be coated on the carton. The selective barrier performance of plastic makes it in a microclimate conducive to the preservation of fruits and vegetables, and the good thermal insulation of the carton can maintain a certain temperature and humidity in the carton. An artificial louver packaging container can also be designed, in which an louver is opened on a sealed container, and the window opening part is covered with an "artificial lung" film. This film is made by soaking nylon fiber cloth in silicone mixed solution and drying it. Like a lung, it has good functions of adjusting oxygen concentration and inhibiting respiration, and has a good fresh-keeping effect. In addition, a proper amount of solid preservative can be added into the packaging container, which is made of zeolite, bentonite, activated carbon, calcium hydroxide, etc., and is actually an adsorbent, which can absorb gaseous substances such as ethylene emitted by fruits and vegetables, thus delaying the post-ripening process. When in use, it is packed into a breathable pouch, sealed and then placed in the package.