Cold chain storage should determine the treatment process based on the characteristics of fruits and vegetables
Control elements for process conditions include: process level of cold chain storage, packaging conditions, and sanitation. Taking a fabricated air-conditioning library as an example, its main performance indicators are: the temperature in the library is adjustable from -2 °C to 15 °C, the relative humidity is adjustable from RH75% to 95%, and the O2 content is adjustable from 1% to 10%. The CO2 content is adjustable from 1% to 10%, the ethylene content is below 10PPM, the reservoir gas tightness index (domestic) is limited to 10mm water column, and the residual water column height is not less than 5mm after 10 minutes. The reservoir gas tightness index (foreign) The pressure is limited to 25 mm water column, and the residual water column height is not less than 8 mm after 30 minutes.
Between the cold storage exit and the delivery station is the freight yard, the main function is the passage of goods and goods and the sorting and sorting of goods; the refrigeration system adopts the indirect cooling method of ethylene glycol aqueous solution, which has the characteristics of temperature regulation and flexibility compared with the direct evaporating system. The chiller is used for cooling in the warehouse, and the floor-standing chiller is used in the air-conditioning room. In the air-conditioning system, the hollow fiber membrane nitrogen generator, the carbon dioxide removal machine and the centrifugal spray humidifier are used, and the air-conditioning station is used for each air-conditioning. Centralized adjustment and distribution; the air conditioning of the freight yard adopts a return air supply mode, and the fresh air and indoor return air are sent out by the air duct after being processed by the wind cabinet.
The optimum preservation temperature of Chinese cabbage, garlic, onion, spinach, etc. is usually -1 ° C ~ 1 ° C, the relative humidity is usually 90% ~ 95%; the appropriate preservation temperature of bell pepper, kidney bean, cucumber, tomato, etc. is higher, Usually 7 ° C ~ 13 ° C, relative humidity should be controlled at 85% ~ 95%; apple preservation temperature is controlled at -1 ° C ~ 1 ° C, relative humidity is 85% ~ 90%; grapefruit cold storage temperature needs to be controlled at 0 °C ~ 10 ° C, according to different varieties of grapefruit to adjust the specific preservation temperature, the relative humidity is usually 85% to 90%; pear cold storage temperature is usually 0.5 ° C ~ 1.5 ° C, relative humidity of 85% ~ 90%.
The process parameters of fresh-keeping storage of fruits and vegetables are broad-spectrum and must be reasonably formulated and implemented according to the quality of specific fruit and vegetable varieties, warehouse equipment configuration, cold chain management and operation mode.
Reprinted from the network