Storage and fresh-keeping Technology of Potato

The storage methods of sweet potato: first, the timely and harmless harvest of sweet potato is closely related to safe storage. The harvest is too early and the temperature is still high, so it can not be stored in the cellar after harvest. If the harvest is too late, the sweet potato subject to frost in the field is prone to chilling injury during storage. The harvest usually begins when the temperature drops to 15 ℃ and is finished before the frost. The skin of sweet potato is thin and brittle, and it is very vulnerable to damage during harvest and transportation. this kind of damage can easily lead to bacterial infection and rot. Therefore, sweet potato needs to be treated with callus before storage. The specific method of callus treatment is to give 3035 ℃ and 90% 95% relative humidity immediately after harvest, and store it under this condition for 4 days, so that the damaged surface protection structure can be repaired. Callus treatment should be carried out immediately after sweet potato harvest, and the shorter the interval, the better. During the callus period, attention should be paid to ensuring adequate ventilation to prevent the accumulation or hypoxia of C02or the production of condensed water. The callus should be carried out in the storeroom or cellar. Once the callus is over, it should be changed to the normal storage temperature and humidity, and it will not be moved in the future to prevent new trauma. Second, the suitable temperature for storage of sweet potato is 1315 ℃, and the relative humidity is 85% and 90%. Sweet potato is particularly sensitive to low temperature, chilling injury will occur when stored below 13 ℃. The symptom of chilling injury is the internal deterioration of sweet potato, brown or black, with peculiar smell and hard heart after steaming. Third, storage mode and management 1. Indoor storage can choose a tight and warm house, build a fire path around the wall, build a stove for heating, and build a hoard on the ground, which is 1-1.5 meters high and 1.5 meters wide, depending on the size of the room and the amount of storage. Hoard the bottom and around the pad appropriate amount of bean leaves, play the role of cold protection and heat preservation. When hoarding sweet potatoes, be sure to handle them gently to avoid damage and get rid of diseased sweet potatoes. Then make a fire to heat up the callus, and after the callus is cooled through the air bucket on the window. Later, with the drop of temperature to seal the doors and windows, cover the sweet potato with 6-9 cm thick bean leaves, when the weather is cold, cover a layer of grass curtain to prevent the cold, and light a fire to warm up properly. 2. The cellar storage chooses the place with high topography, solid soil and low groundwater level, and dig down a wellbore with a diameter of about 1 meter and a depth of 5-6 meters. A soil platform is left in the middle of the bottom of the wellbore, and then a hole with a width of about 1 meter and a height of about 1.5 meters is dug from the bottom of the well to the horizontal direction on both sides, and then expanded into a storage room after digging into about 1 meter. The size of the storage room can be determined according to the amount of storage. The storeroom, which is 1.5 meters high, 1.5 meters wide and 2 meters long, can generally store 1 500 to 2000 kg of sweet potato. The mouth of the pit should be about 30 cm higher than the flat ground to prevent Rain Water or snow water from flowing into the cellar. The storage room should be covered with dry sand 10 to 15 centimeters thick, on which sweet potatoes should be placed. Sweet potatoes can only be filled with 70% full, so as to leave room for air exchange, otherwise they will rot worse because of dampness and heat. When the staff go down to the well for management, they should pay attention to prevent the suffocation of CO2 in the well.