Storage and fresh-keeping Technology of Grape

Grape is one of the fruits that we often see in our daily life. It tastes sour and sweet, and the price is more affordable. However, grapes are extremely easy to attract mosquitoes, and can not be kept fresh for a long time, and should not be kept for a long time. In the grape market season, due to the great pressure of sales, many growers have to choose to sell at a lower price, or even at a loss, in order to solve this problem. The most important thing is to be able to effectively store grapes. Grapes have no post-ripening process, so they have to be harvested after they are fully ripe, and grapes that are not ripe are not resistant to storage. The following pro-agricultural network will introduce to you: the storage and preservation technology of grapes.

I. We should pay close attention to the pre-harvest management.

Increase the sugar content of grapes, you can enhance the storage resistance. The application of organic fertilizer can not only increase the yield, but also improve the quality, sugar content and storability. With the application of too much available nitrogen fertilizer and partial application of nitrogen fertilizer, especially in the middle and later stage, the quality of grape will decrease obviously and it is easy to decay and deteriorate during storage. In order to improve the yield, sugar content and storage tolerance, organic manure such as ripening, water, human manure and urine can be applied once in the middle and later stages of grape growth, with 500 kg per mu in furrows or 700 kg in holes. 15-20 days before grape harvest, except for those with severe drought, they should not be watered, otherwise the storability will be reduced. When the grape is harvested, the 14-13 soft tips (grains) at the lower end of the ear should be cut off. This part of the fruit is small, low in sugar content and perishable, and must be cut off.

II. Scientific harvesting and pre-cooling treatment

There are many varieties of table grape, and there are great differences in storage tolerance among different varieties. Generally speaking, most of the very early-maturing and early-maturing varieties are not tolerant to storage, the late-maturing varieties have good storage tolerance, and the storage tolerance of the middle-maturing varieties is mostly between the two. Jufeng, Balgal, white rose incense and other good storage resistance, milk, Sabah pearls and other not resistant to storage, rose incense and other medium storage resistance. Grapes have no post-ripening. In order to maintain the quality of stored fruits, grapes should be harvested after full maturity, not too early or too late. Cloudy days, dew dry morning or evening is the most suitable for harvesting, rainy days, hot sun can not be harvested. Bamboo, wood or cardboard boxes can be used to ship grapes. These appliances should be exposed to the sun for 1 or 2 days before use, and then lay sterilized scraps of paper around the box and at the bottom to prevent the sharp parts from damaging the fruit. It is appropriate to pack 15kg or 20kg of grapes in each carton. Too much or too little is not convenient to carry. Different varieties of grapes should be harvested, stored and transported separately, and should not be mixed, mixed and stored. Fruit picking should be done with fruit shears, light picking, light handling, light loading, light transportation and light unloading. Do not pull hard or throw at random. The post-harvest grapes should be spread out in a cool and ventilated place for pre-cooling treatment for 1-2 days, and it is best to put 0: 1 ℃ pre-cooling room for 24 hours before storage.

III. Disinfection of storage places

Storage places and appliances should be carefully cleaned before storing grapes, and a layer of quicklime powder should be sprinkled on the ground, 20% quicklime water should be sprayed around the walls, and then every cubic meter of space should be fumigated with formalin 10: 15 grams airtight for 6 hours. After opening the door and window ventilation to remove the smell of medicine, it can be stored.

IV. Storage and preservation method

1. Cellar storage. The cellar or air-raid shelter used to store apples and pears can be used to store grapes with a little finishing. A wooden or iron frame with a width of 100 cm and a height of 30 cm to 40 cm is set up in the cellar, on which the grapes can be placed. Check every 15-20 days during storage, remove diseased and rotten grains in time, and ventilate every 7-10 days. The suitable storage temperature of this method is 3-4 ℃, the relative air humidity is 85%-90%, and can be stored for 70-100 days.

two。 Storage of ordinary bungalows. The storage room is required to be high-lying, cool and sheltered from the wind, with no or little rodents and insect pests, low groundwater level, good tightness, and automatic refrigeration equipment should be installed. Build a 2-3-story wooden or iron frame indoors, put the grape ears gently on the rack, and cover the top with disinfectant paper. The boxes or baskets containing the fruit can also be placed on the shelf. Keep room temperature 0: 1 ℃ during storage, relative air humidity 85%-90%, check and ventilate every 7-10 days. This method can be stored for 2 to 3 months.

3. Hang it. Use wood or iron bars to set up frames in cellars or bungalows, and hang grape ears on wood or bamboo poles. This method is most suitable for storing late-maturing varieties, but not for early-maturing varieties. During storage, the temperature should be kept at 0: 1 ℃, the relative air humidity should be 85% and 90%, and ventilation should be done every 7-10 days. This method can be stored for 2 to 3 months.

4. Gouzo. The selected land should be high topography, low groundwater level, solid soil layer, no rats and insects, shelter from the wind, shade, short or no lighting time, etc. The trench is in the north-south direction, with a width of 1 meter at the top and a width of 30 cm at the bottom and a depth of 80 cm. After the trench is excavated, the bottom is covered with 7cm dry fine river sand, and then 2.5% deltamethrin EC and 3000 times solution are sprayed to the bottom and both sides of the ditch. After that, the grape ears are gently placed on the dry fine river sand, with a total of 3 layers of fruit ears, the top covered with a thin layer of clean straw or newspaper, etc., and finally build a "human" bracket on the ditch, cover the straw mat on the shelf during the day, and open it at night. When the outside temperature drops to 1: 2 ℃ during the day, straw mats should be covered day and night; when the outside temperature drops below 0 ℃, grass mats should be covered to prevent freezing. The optimum temperature for ditch storage is 3-4 ℃, and the relative air humidity is 85%. This method is only suitable for the northern producing areas and can be stored for 60-80 days.

5. Refrigerated storage. The bamboo or wood baskets that have been loaded with grapes are stacked in the library in the shape of "product". The height of the pile should not exceed four baskets, leaving more than 1 meter wide aisle between the stacks to facilitate operation, etc. Grapes should be stored alone, not with or mixed with other fruits. Different grape varieties and grapes at different ripening stages should also be stored separately. The optimum temperature for cold storage is 0: 1 ℃, and the relative air humidity is 90%-95%. It should be ventilated every 7-10 days during storage. This method can be stored for 3 to 4 months.

6. Easy storage at home. When the grapes are in small quantity or buy a small amount for fresh food such as Chinese New year, they can be stored in cans or jars, and the fresh-keeping effect is also good. According to the number of grapes stored, choose a jar or jar suitable for size, wash the jar with clean water beforehand, then dry the water with a dry towel, wipe the inner wall with cotton ball dipped in 70% alcohol, gently place the grapes layer by layer after drying, each layer is 10 to 15 centimeters thick, then put the grapes on the bamboo curtain, and then put the grapes on the bamboo curtain until the jar is full, and finally seal the vat with a non-toxic plastic film and put the jar in a cool place without light. If the grapes are stored in the altar with a smaller mouth, the jar sealed with non-toxic plastic film can be buried deep in the pit and covered with 20 cm thick soil. This method can be stored and kept fresh for 1-2 months.

The above is the storage and fresh-keeping technology of grapes introduced by pro-agricultural network, we can see that through this method, most grapes can be stored for 1-2 months, and the storage time can be up to 4 months in cold storage. this not only realizes the long-term storage of grapes, but also bypasses the listing season of grapes, realizes out-of-season listing, and improves the income of growers.