Preservation methods of the latest spinach

Spinach is nutritious, especially tender and delicious in spring, but in fact, from picking to being put on the table, spinach will lose nearly half of its nutrition because of improper preservation, so how to preserve spinach? Now let's take a look at the preservation methods of spinach.

The selection and purchase method of spinach

1. It is better to buy vegetables with short red stems and fresh and elastic leaves.

2. Choose spinach with thick leaves, well stretched leaves, wide leaves and short petioles. If there is discoloration in the leaves, they should be removed.

Preservation methods of spinach

Spinach is extremely perishable, as long as it is above the freezing point (close to 0 ℃), the lower the temperature, the longer the storage life, close to 0 ℃ storage, about three weeks. With the increase of storage temperature, the storage life is shortened rapidly.

Crushed ice can be used during transportation and put on top of spinach to achieve the effect of rapid precooling. In addition, we should still pay attention to the maintenance of humidity to prevent dehydration, but do not have condensed water attached to the leaves, so as not to increase the decay rate. Spinach can be stored in plastic bags with holes, which can not only reduce water loss, but also reduce physical damage. Atmospheric storage of 10% 40% carbon dioxide and 10% oxygen can prevent leaf yellowing and maintain quality.

The method of storing spinach in winter

1. Ordinary frozen method: spinach that needs to be refrigerated is generally frozen on the ground at night, and can be harvested at noon. Take 1.6 cm long roots when harvesting, shake the soil, arrange the bundles, about 2 kg each, put in a cool place to dry the dew, and make the vegetables cool, freeze when the weather turns cold. The storage site should be selected in a shaded place, leveling the ground, digging a number of ditches of 3.5 cm in width and depth, with a spacing of 10 cm to 15 cm, and put the spinach root down into the ditch with a total thickness of about 25 cm. In the cold season, you can cover it with grass grass, etc., and keep the temperature in the ditch at-8 ℃ 5 min.

2. Spinach frozen storage method without ventilation: in the shade area to the north of the house or shade barrier, dig several ditches parallel to the shade, the ditch width is 25cm 30cm, the depth is the same as or slightly shallow as the spinach height, and the distance between the ditch and the ditch is about 20cm. The pre-stored spinach bundles are placed upright in the ditch with the roots upright, and the dry soil is sprinkled on the vegetable bales. The thickness of the soil is appropriate to just cover the spinach. After that, with the decrease of temperature, the soil should be covered step by step, and the soil cover should be flat and seamless, which can protect against wind and moisturize. The principle is to keep the temperature in the bundles at-4 ℃ as much as possible, so that the spinach is slightly frozen.

3. Ground freezing method: 5-6 days before harvest, level the site and pour a layer of water to ensure that the topsoil is not thawed. When storing vegetables, first sprinkle some vegetable leaves or leaves to cover the bottom, then put bundles of spinach on top, and then cover them with vegetable leaves or leaves 10 to 12 centimeters thick. When the inside of the spinach freezes, cover it with 10 cm thick and semi-dry sand to prevent the leaves from losing water.

4. Bagged spontaneous controlled atmosphere cold storage method: the harvested spinach is bundled into 0.5 kilogram spinach handles. after heat dissipation and pre-cooling, the spinach is packed into a polyethylene film bag with a thickness of 0.06 to 0.08 mm and a thickness of 110 × 80 centimeters. the leaves are opposite to each other, with the roots facing both ends of the bag, each bag is about 15 to 20 kilograms, and put it flat on the shelf of the cold storage, then precool the opening for a day and night, then insert a round stick with a diameter of about 2 centimeters into the bag and tie it tightly. Then pull out the round stick, or loosen the mouth of the bag, and leave a large gap in the bag. After sealing the bag, it is placed in a cold storage with a temperature of-1 ℃ and 90% to 95% relative humidity. Relying on the spontaneous metabolic activity of spinach in the bag to absorb oxygen and carbon dioxide, it can gradually form a gas environment with lower oxygen and higher carbon dioxide, at the same time, the internal humidity condition is good, and it can be kept fresh for 2 to 3 months with little loss.

5. The method of combined border frozen storage: select the land with strong growth of spinach and the combination of frozen storage, with three beds for each combination, one on the left and one on the right, and the middle one on the frozen storage. Before frozen storage, first use a shovel to shovel off the roots of the frozen border vegetables, its depth is 1.5 cm, do not disturb the vegetable plants. In the same method, the left and right rows of spinach were shoveled and covered on the frozen border in the middle, with the leaves facing down and the roots up, and the spinach from three borders formed one bed. On the day of storage, bury the surface of the bed with soil and pat it gently to make the spinach close between the upper and lower layers to prevent the cold wind from entering. When the temperature is too low, cover a layer of fine soil 7 to 10 centimeters thick. Using this method, the Spring Equinox can be stored until the following year.