Scientific storage and transportation methods of C

Scientific storage and transportation methods of Castanea henryi

Castanea henryi is a pollution-free natural green food with large, round and bright grains, fragrant, waxy and sweet, delicious flavor and rich nutrition In particular, because of its high sugar content, good waxiness, tender meat, astringent skin and easy peeling, Castanea henryi is superior to chestnut in quality, and has become an important famous and high-quality characteristic fruit in the mountainous areas of Northern Fujian, which is exported to all parts of the country and favored by the majority of consumers

Castanea henryi is a dried fruit with shell, which is more convenient in packaging and transportation than other fruits, but it is not as durable as other dried fruits, nor can it be stored and transported after drying like other dried fruits Fruit farmers in the chestnut area said that there are "four fears" in the storage and transportation of Castanea henryi, namely "fear of drying, fear of heat, fear of freezing and fear of stuffy". During storage and transportation, due to improper conditions and poor management, water loss, air drying (weight loss), insects, teeth and decay are often caused, especially the spots of chestnut kernel, causing serious losses. Therefore, good storage and transportation of Castanea henryi can not only maintain the quality and flavor of Castanea henryi, but also avoid post harvest losses and improve the economic benefits of Castanea henryi farmers

first, harvest timely and scientifically to ensure that the cone fruit is fully mature

harvest timely and scientifically to ensure that the cone fruit is fully mature is the premise of doing a good job in the storage and transportation of Castanea henryi. Immature Castanea henryi has poor nutritional components, color and flavor, high water content and weak disease resistance, which is easy to cause water loss, air drying and mildew loss in storage and transportation. Different varieties of Castanea henryi have different maturity periods. The most early maturing varieties, such as bailuzi, mature in early September, and most late maturing varieties mature from late September to mid and late October. Generally, cones of late maturing varieties should be selected for storage, with good storage resistance

the sign of full maturity of Castanea henryi is that the chestnut bract changes from green to yellow and cracks, and the cone fruit in the bract changes from yellow to brown and has oily luster. At this time, it is the appropriate time to harvest. China is a major producer and consumer of plastic products in the world. In order to ensure the full maturity of cone fruit, the chestnut picking method should be advocated when harvesting, that is, picking up after the chestnut bud on the tree cracks, the chestnut fruit is exposed and falls off the ground by itself. In order to facilitate the picking of chestnut fruits, weeds on the ground should be removed and the soil hoed before the chestnut bud cracks. If you are in a steep mountain, you must also make a cushion under the steep slope to prevent the chestnut fruit from falling and rolling away. It is best to pick it up once a day in the morning to avoid drying the chestnut fruit by the sun at noon, and the high heat in the field is not conducive to storage. The Castanea henryi harvested by this method is full and full, the peel is fully colored and shiny, the pulp is sweet, the flavor is good, and the nutritional composition is high, and it has a strong ability to resist adverse environmental factors in storage, such as excessive bottom temperature and the role of various bacteria, and has a strong storage resistance

II. Do a good job of pretreatment before storage and transportation to improve the storage resistance

1 Sweat to dissipate heat. Most of the harvest of Castanea henryi is from late September to October. At this time, the temperature is high, and the cone fruit falling out of the cone bud also has high field heat and temperature. It needs to be spread out in time to cool and dissipate the heat of the Castanea henryi. The masses call it "sweating". Otherwise, the chestnut fruit will have high water content, high temperature and vigorous respiration, especially in the case of poor ventilation in the storage place and a large amount of accumulation, the chestnut field heat and respiratory heat are not easy to spread, and the temperature will rise sharply, resulting in the fermentation and corruption of germ and cotyledon. Therefore, after "sweating", it can quickly reduce the field heat, reduce the respiration of chestnut fruits, and reduce decay. The sweating and heat dissipation of chestnut fruits can be carried out in a ventilated and cool room or under a shade. Generally, sweating for two days is enough

2. Fumigation kills insects. After harvest, Castanea henryi should be fumigated to reduce the damage of weevils and peach borers during storage and reduce losses. The common treatment method in chestnut area is carbon disulfide (CS2) fumigation. A fumigation room with good sealing performance should be selected, and the chestnut fruits should be spread indoors, with a thickness of no more than 60 cm. The chestnut fruits can also be put into breathable containers such as gunny bags or bamboo baskets, and then the containers containing carbon disulfide should be placed on the chestnut pile or chestnuts. 7. Ensure that the motor circuit of the universal material experiment has a good grounding state, and the bags let the carbon disulfide volatilize and vaporize and gradually diffuse downward, so as to achieve the purpose of fumigation and insect killing. Every 50 cubic meters of fumigation room should use 1.5-2.5 kilograms of carbon disulfide. It is said that this mobile phone is a tribute to the Pioneer 10 spacecraft. When the temperature is high, the dosage should be less, and when the temperature is low, it should be more. In order to ensure the fumigation effect, carbon disulfide should first be stored in multiple vessels and placed at multiple points, so that the carbon disulfide gas can be evenly diffused to all parts of the fumigation room, so as to achieve the purpose of uniform and complete insecticidal; Secondly, when fumigating and killing insects, the doors and windows of the fumigation room should be closed tightly, and the door seams should be sealed with kraft paper to avoid the leakage of chemicals. Generally, fumigation for 24 hours can kill all eggs and pests, and then open the doors and windows, and take out the chestnut fruits after the gas diffusion

III. select appropriate storage methods to ensure the storage effect

1 Sand storage method. This method is simple and suitable for chestnut farmers in production areas. Choose a cool indoor ground to be paved with 10 cm thick clean wet coarse river sand. The humidity of the sand is based on the fact that the hands can form a mass and the hands can be loosened. The upper layer of chestnut fruit and sand are placed in alternating layers, each layer is 5-10 cm thick, or a portion of chestnut fruit and two portions of sand are mixed and stacked. Finally, the sand is covered by about 10 cm, and the upper side is covered with straw, with a stacking height of 0.5-1 M. During storage, check every 15-20 days to release heat and pick out rotten grains. Generally, the surface of normal chestnut fruit is basically not covered with river sand, while the rotten grain is covered with river sand. In order not to be polluted during sand storage, it is best to choose soilless clean river sand, sun it for 2-3 days before use, add 5% clean water when using, and dissolve 0.1% methyl mop in the water. This method can be stored for 2-3 months, and the decay rate is 2% - 3%

2. Cold storage method. This is a commonly used method for storing a large number of chestnut fruits at present. Due to the better control of storage temperature and humidity, the loss of chestnut fruits is less, and there is basically no germination phenomenon. The storage period is long and the effect is good. Human stored chestnut fruits should be fully mature and bright in color, eliminate pest fruits, dried fruits, moldy fruits, deformed fruits, mechanically damaged fruits, etc., and grade according to the weight of a single grain. Refrigerated chestnuts must be packed in double gunny bags lined with soaking wet gunny bags or perforated plastic bags lined to maintain the humidity of chestnuts. When entering the cold storage, it should be stacked scientifically, generally in the form of "well" or "product". The goods stack should be about 30 cm away from the wall. Appropriate gaps should be left for each sack in the stack, and walkways should be left between the stacks for ventilation, cooling and inspection. During cold storage, the temperature should be 1-3 ℃, the relative humidity should be 90% - 95%, and the carbon dioxide should not exceed 3%

3. Controlled atmosphere refrigeration. This is an advanced method in chestnut storage at present. Good storage effect can be achieved by adjusting the air components in the storage environment and combining with low temperature refrigeration. When the carbon dioxide is below 10%, the oxygen is 3% - 5%, the temperature is about 0 ℃, and the relative humidity is 9, the chestnut fruit is still fresh and full after 120 days of storage, and the quality is good

IV. transportation should be carried out reasonably to ensure the safety of external transfer

Castanea henryi is required to maintain low temperature and high air humidity conditions in the transportation process. The chestnut fruits transported by external transfer are generally packed in wet gunny bags, and they should be quickly collected, packed, transported, heat proof, antifreeze, and dry proof, so as to shorten the turnover time of chestnut fruits as far as possible and ensure the commodity quality of chestnut fruits. The main links of its outward transportation can be summarized as follows: timely and scientific harvest → sweating and pre storage → timely purchase → selection and classification → sack packaging → fumigation and insect killing → pre cooling and moisturizing → vehicle night transportation → port cold storage preservation → refrigerated ship export outward transportation

source: Fujian Agriculture