Storage and preservation of plum fruit

1. Cold storage: under the condition of storage temperature of 0 ℃ and relative humidity of 90%, plum fruit can only be stored for a short time, about 1 month. If stored in cold storage for too long, flesh browns and odors occur.

2. Controlled atmosphere storage: pre-cooled and selected fruits are placed in a 0.025 mm thick polyethylene film bag, each containing 5 kg of fruit, and the oxygen content in the bag is controlled by natural or artificial deoxidization at 1%, The content of CO _ 2 was about 5%. Under the condition of 0 ~ 1 ℃, plum fruit could be stored for 10 weeks, and the decay rate was lower.

The main results are as follows: (1) the plum fruits were stored in 0.025 mm thick polyethylene film bag for 70 days under the condition of 0 ℃, 7% carbon dioxide, 1% oxygen, 7% carbon dioxide and 3% oxygen. It can significantly inhibit the fruit decay, softening and the decrease of soluble solids. Different varieties can be adjusted according to this condition. Under the conditions of 0 ℃, 90% relative humidity, 95% relative humidity, 3% carbon dioxide and 94% nitrogen, the effect of storing plum is also better.

(2) Prunus plums collected at the right time will be removed by air-controlled refrigeration in a small package. After removing the damaged fruits caused by diseases and insects, a small bag of polyethylene film is packed, each bag is 1.0 kg 1.5 kg, sealed and placed at-1 ℃, it can be kept for 2 months for 3 months. If the bag contains 3% carbon dioxide, 4% oxygen and 3% oxygen, it can be stored for 3 months and 4 months.

3. Ice cellar storage, cold storage is a traditional natural cryogenic storage method in China. The north collected natural ice or sprinkled water before and after Greater Cold to make ice. The ice is 0.3 m ~ 0.4 m thick and 1 m long and wide. It is stored in the underground cellar and used to store and cool the plum fruit when it matures in summer. Select good storage-resistant plum fruit, timely no injury harvest, pre-cold and then packed for ice cellar. Leave 0.5 m thick ice on the bottom and walls of the cellar, stack the box on top of it, and fill the gap with crushed ice, one layer of ice box, one layer of ice, and one layer of ice at the bottom of the cellar and the walls of the pit. The top of the stack is covered with heat-insulating materials such as straw about 1 meter thick to keep the temperature relatively stable.

The method can store fresh plum stored in late August to the Beginning of Winter or New Year's Day if it is moved into ordinary pit for further storage. In ice cellar storage, attention should be paid to the sealing of pit door and the temperature of pit should be controlled at-0.5 ℃ as far as possible.