Fresh Jujube Cold Storage Technology

Jujube is an important fruit resource with unique characteristics in China. It has been cultivated for more than 3,000 years. Fresh dates are sweet and delicious, rich in nutrition, sweet and crisp in taste, but fresh dates are prone to dehydration, rot, and fermentation, resulting in losses, affecting the preservation and circulation of fresh dates. Constant temperature refrigeration is an effective method to solve the long-term preservation and extension of fresh dates. The cold preservation techniques are summarized as follows: (a) Variety of fresh dates is selected, and there is a large difference between mature dates and storability. Generally, late-maturing and very late-maturing cultivars are selected as storage species, such as Bozao jujube, September green and winter dates and so on. (2) Timely harvesting of ripeness of jujube is one of the important factors that directly affect the fruit storage effect. Different degrees of ripening, the good fruit rate in storage is significantly different. The fruit ripeness of jujube fruit with low ripeness (green and white in peel) was significantly higher than that in ripeness (half of the skin color turning red) and fruit with high maturity (red skin color turned red). Therefore, as a storage species should be selected when the harvest is low, pay attention to hand picking, requires no disease, no insects and the size of the same. Separate fruits of different maturity. (3) Fresh dates used for packaging and transportation are stored in plastic crates or special cartons. After getting into the box within 12 hours, it should not be stored for a long time. In the process of transportation, it should be lightly loaded and unloaded to prevent extrusion and bumping and fruit damage. (D) graded packaging, anti-corrosion treatment according to the size and maturity of fruit packaging, each box up to 10kg. The box is lined with 0.02 mm thick perforated polyethylene (ethylene absorber is potassium permanganate supported with vermiculite or tiles). Then seal the box, TBZ fumigation (3-5g/m3). (v) Before the storage, the Treasury manages the storage of the warehouse to conduct insulation tests to ensure that the temperature during storage is stable. After confirming that the temperature is correct, the warehouse shall be sterilized. Each m3 storage volume shall be fumigated with 10-15 g of sulphur for 24 hours, or be sterilized with 2%-3% of formalin for 24 hours. Store the temperature of the warehouse down to -2°C before storage to prevent the temperature of the warehouse from recovering after the fresh dates are stored. (6) Storage conditions are generally required to be stored within 24-48 hours of harvesting, filled within 1-2 days, and the suitable temperature in the storage room is 0°C-1°C. The suitable proportion of gas in perforated plastic packaging is O23%- 5%, CO2 (7) Precautions 1. During the entire storage operation of fresh jujube, the operation time should be shortened as much as possible. Otherwise, the pulp slurry will be rotten because of its own respiration heat. 2, fresh dates breathing intensity, packaging plastic bags must be punched, otherwise it will cause anaerobic respiration, accelerate the browning process. 3, storage temperature 0 °C - 1 °C refers to the date temperature, not the temperature of the warehouse.