1, a new plastic cling film Japan introduced a disposable fruit and vegetable cling film, which is composed of two highly transmissive nylon translucent film, a layer of sand syrup between the two layers, in order to make the packaging film can be slow Absorb moisture from the surface of fruits and vegetables to achieve preservation. A Japanese food company also produced a fruit fresh-keeping box that added a layer of polyethylene film on the corrugated cardboard inside of the corrugated box, and then applied a layer of waterproof wax coating containing a trace amount of fruit disinfectant to prevent evaporation of fruit moisture. Inhibit their breathing. 2. Edible fruit preservatives Ameri-Agricultural Foods of the United States has developed an edible fruit preservative, which is a translucent liquid made from sugar, starch, fatty acids and polyesters. It can be sprayed and impregnated. The method of brushing covers the surface of fruits such as apples, pears, oranges, bananas, or tomatoes. Because this preservative forms a layer of sealing film on the surface of the fruit, it can prevent most of the oxygen from entering the interior of the fruit, thereby inhibiting the ripening process of the fruit and extending the preservation period. This preservation can be eaten with the fruit. 3. The electronic preservation fresh-keeping machine uses the negative oxygen ions and ozone generated by the high-voltage negative-electricity site to achieve the preservation purpose. Negative oxygen ions can purify fruits and vegetables through metabolic processes, thereby reducing the degree of respiration of fruits and vegetables and reducing the production of ethylene as a ripening agent. Ozone is a strong oxidant, and it is also a good disinfectant and bactericide. Kill and eliminate microorganisms and their secreted toxins on fruits and vegetables, inhibit and delay the decomposition of organic matter, thereby prolonging the storage period of fruits and vegetables. 4, high-temperature treatment preservation method Britain has invented a high-temperature technology to inhibit the germination of bulbous vegetables, the storage room temperature is controlled at 23 °C, relative humidity maintained at 75%, so you can achieve long-term storage and preservation purposes. However, under such temperature conditions, vegetables are prone to produce saprophytic fungi and cause lesions. At present, the United Kingdom is developing how to control this saprophytic fungus. According to reports, onions can be stored under these conditions for 8 months. 5, decompression treatment preservation method This preservation method is the application of reduced air pressure, with low temperature and high humidity, and the use of low-pressure air circulation and other measures to create a favorable storage environment for fruits and vegetables. Mainly rely on the vacuum pump to remove the indoor part of the air to form a low pressure control below 100mm Hg, the lowest is 8mm Hg. The relative humidity in the air is controlled by the humidifier, usually more than 90%. This method reduces the oxygen content in the room during the evacuation process, keeps the respiration of the fruits and vegetables at the lowest level, and also eliminates some of the indoor gases such as carbon dioxide and ethylene, thus facilitating long-term storage of fruits and vegetables. 6, cold temperature and high humidity storage method it can greatly extend the fruit preservation time, and will not cause adverse effects on the fruit. Its approach is: to adjust the temperature of the cold room to 0 to 1 degree Celsius, adjust the humidity to 95%, and inject a mixture of negative ions and ozone. Its advantage is that some fruits can not withstand low temperatures, but high humidity can solve this problem; low concentrations of ozone can not be sterilized, but with the addition of negative ions, the bactericidal capacity has been significantly improved, will not have adverse effects on the fruit. Compared with the previous method, the preservation time of peaches, grapes and pears can be prolonged by 5 times, and the citrus can still be eaten after being removed for 5 months.