The water content of fresh fruits and vegetables up to 65 ~ 96 %, but after losing to add water collected in the storage and transport gradually wilting , declining to make weight , the direct economic losses caused . In addition , dehydration can also cause loss of fresh product , under normal circumstances , fruit and vegetable dehydration 5% appeared wilting and collapse , in a warm , dry environment for several hours , most of the fruits and vegetables are wilted . Some fruits although not to the degree of wilting , but dehydration of fruits and vegetables has affected taste, crispness , color and clear plastic box flavor.Fruits and vegetables can cause wilting metabolic disorders that increase the hydrolytic activity , such as sweetened dried sweet potatoes , because of dehydration caused by the hydrolysis of starch to sugar results. When fruits and vegetables severe dehydration , cell concentration increased, some ions such as ammonia and plastic case hydrogen ion concentration is too packaging company high will cause cell toxicity , or even destroy the colloidal structure of protoplasm . Organizations can cause excessive water loss and stimulate ethylene content increased ABA synthesis vac tray , accelerated aging and falling organ . Thus, in post-harvest handling of fruits and vegetables, and storage and transportation process should try to control water loss . But there are some exceptions , such as onions , garlic should be properly stored before drying , dry scaly accelerate and promote products dormancy, moderately dry cabbage leaves so mild dehydration, can reduce the freezing point and improve cold tolerance .Wilting destroyed the normal metabolism of fruits and vegetables , the hydrolysis process enhanced cell turgor pressure drop caused by the mechanical properties of structural change , will inevitably affect the fruit and vegetables storability and disease resistance . The greater the degree of tissue dehydration wilting , the more vulnerable to microbial infection , disease resistance fall faster.Postharvest measures to prevent water loss1 package , waxing or coatingThe easiest way to reduce dehydration of fruits and vegetables is to use a plastic film or other waterproof material to cover up the product , the product can also be packed in a bag , box or tray. Polyethylene film is preferably waterproof material. But we must note that the product is packaged in reducing water loss while also reducing the cooling rate of the product. In addition, water absorption capacity of the packaging material can not be ignored , wax or resin composite package deal package prevents water absorption , although the cost is higher, but there is practical value in business. In addition, we can also wax or paint surface of the product , and then coupled with appropriate packaging to prevent product dehydration.(2) clear plastic packaging increase air humidityAnother effective way to reduce the fruit and vegetable dehydration is to increase the relative humidity of the air , but high humidity favorable for mold growth , and with the use of fungicides. Automatic humidifier to increase air moisture available to the plastics products library spray mists or spray steam , watering can on the ground or in the library hang wet straws ; evaporator condenser or an appropriate increase in humidity , so that the storage temperature is maintained at less than 2 ~ in the range of 3 . In short , the relative humidity within the library maintained at 95% , the product water loss can be avoided .3 . Proper ventilationWhether natural or mechanical ventilation libraries cold adequate ventilation is a must, it can be taken away and the heat load library inside temperature to prevent uneven , but to minimize wind speed of 0.3 to 3 m / s wind speed little effect on product moisture evaporation .4 Use cold sandwichThe library consists of two layers of sandwich walls composed cold , cold air circulation middle , both heat and moisture the outer wall , the inner wall is not insulated , the evaporator is disposed between the two walls , by using the conductive library heat exchange . Since the evaporator is not in the library , the product is not captured in the water and frost , high humidity library prevent dehydration products .5 Use Breeze GalleryThe cold breeze library is fed through the top of the porous library library or to go through the cold air humidifier and then sent to the library , you can effectively prevent water loss

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