1, room temperature storage. Lychee without any preservatives, generally 5-7 days on all the brown. At present, room temperature storage generally have to combine the preservative effect of drugs to achieve the purpose of storage, can promote the preservatives are benlate, benomyl, polymyxin, fungicide, ethylphosphorus aluminum, Tecdol, pohayin and so on. Large-scale productive ambient storage and transportation often do not get the desired effect of freshness, freshness is only about 1 week, for about 5 days of short-term storage and transportation.
2, low-temperature spontaneous air-conditioning storage. This method requires no dramatic fluctuations in temperature during storage, carbon dioxide does not exceed 10%. Polyethylene film plus carton packaging, 5 kg per box, at a temperature of 1-3 ℃, relative humidity 85% -90% or more, can be kept fresh for 20-30 days. Fresh lychee with 0.24-0.25 mm thick polyethylene bags sealed package, 15 kg of fruit per bag, at 1-5 ℃, can be stored for 30-40 days. 7-8 mature lychee, in plastic film bags, 5 ℃ can be stored for 47 days.
3, low temperature storage. Selected maturity, no pests and diseases of lychee fruit, after antiseptic treatment, sealed in a small plastic box packaging at low temperature storage. Storage at 5 ℃ storage storage 30 days good fruit rate of 85% -88%, but lychee in cold storage is prone to cold damage, 1 ℃ storage 30-35 days will suffer irreversible cold damage; 5 ℃ storage 30-30 days caused by cold damage can be reversible, move back to room temperature can be restored to the quality of the fruit. In the cold storage should pay special attention to the constant temperature of the library and in the harvest to the storage time should not exceed 12 hours, and to use small packages, in the storage process should not open the small package.
4, foam box with ice. The whole process requires careful operation, quick action, light take light put, from harvesting to loading requirements in 4-6 hours to complete. Foam box with ice lychee storage and transportation preservation technology, generally after 3 days and nights of transportation, lychee still maintains the original bright red, unchanged flavor, good fruit rate of 93% or more, water loss of no more than 3%. However, it is easy to cause carbon dioxide damage to the fruit with a bad taste, and therefore only suitable for 3-4 days of short-distance transportation use to ensure that the arrival of 2-3 days of sales time.
5, chemical treatment.
①Smoke sulfur dip acid: sulfur treatment and dip acid recolor, can effectively prevent litchi browning, keep the peel red. South Africa, Israel and other exports of lychee to the European market using this technology, some producing areas in China have also begun to use the technology. Fumigation with 0.6% sulfur dioxide for 15 minutes, pulp sulfur residue of 6PPM, and then acid treatment for 30 seconds, can restore the intensity of litchi rind red, improve the fruit cracking rate and water loss during storage.
② Conventional fungicides: in lychee to inhibit myclobutanil, ShiBaoKe, ShiBaoMeng, TeKeDuo, ethylphosphine aluminum and other fungicides antiseptic effect is better. Fungicide antiseptic treatment, can effectively reduce post-harvest decay; fungicide hot liquid treatment can improve the antiseptic effect, but the hot drug treatment requires specific facilities, the current production has not yet been popularized.
6, hot water and acid dip treatment. The use of 98 ℃ hot water treatment of lychee 3 seconds, only the outer pericarp is affected, while the inner layer of mesocarp and endocarp is not affected, and then after pH 0.5 HCI treatment, can make the lychee pericarp to restore the red color, but the color and the natural color has a certain difference, and the shelf life is shorter. The use of 100 ℃ boiling water scalded and bleached for 7 seconds, can make the lychee pericarp activity compared to the control is reduced by about 5 times or so, and then use 3% citric acid treatment, can make the pericarp show bright red color. The use of 46.5 ℃ 10% citric acid and 0.2% sodium benzoate mixture soaked for 20 minutes, storage at 4 ℃ for 18 days to maintain a better appearance and hardness, but the flavor declined; and the use of 10% citric acid plus 0.2% sodium benzoate treatment for 10 minutes, after storage, fruit hardness and flavor is better, but the color is slightly worse.