How to prevent freezing of vegetables, and how to thaw frozen vegetables quickly?

1. Irrigation and heat preservation Irrigation or watering of frozen vegetables can increase the heat capacity of the soil, prevent the ground temperature from continuing to drop, and reduce frost damage.

2. Pruning and pruning After being frozen, cut off the young shoots and young leaves that have been frozen to death in time.

A processing method for preserving vegetables by freezing them at low temperatures. The pretreated vegetables are quick-frozen at a temperature of -30 -35 or lower, packed in plastic bags, boxes and other containers, or packaged and then quick-frozen, and then stored at a temperature of -18 to inhibit the growth and reproduction of microorganisms and the activity of enzymes, so that vegetables can be preserved for a longer time.

The freezing process and its principleWhen the moisture in vegetables decreases from the initial temperature to below the freezing point of 0, it changes from liquid to solid, that is, freezing. As the temperature decreases, the ice crystals increase, and the vegetables harden and become frozen. The freezing point of vegetables varies depending on the species (Table 1).

Most vegetables begin to freeze at a temperature of around -1, and when the temperature continues to drop to about -5, 70-80% of their water freezes and the vegetables harden. That is, at a temperature of -1 -5, a large number of ice crystals are formed, which is called the maximum formation stage of ice crystals. If the temperature is further reduced to -30 -35, the freezing process is complete.

At different temperatures, there is a corresponding freezing rate of moisture in vegetables (Table 2). Therefore, in order for the water in the vegetable to freeze completely, it is necessary to reduce its temperature to the eutectic point, which is the temperature at which the freezing rate of the water reaches 100%.

Vegetable quick-freezing processing processIn the quick-frozen processing of vegetables, the steps of raw material selection, cleaning, peeling, cutting, and blanching are basically the same as those of vegetable drying and vegetable canning. After blanching, the vegetables should be cooled and rinsed with clean water in time, and then blast frozen at a low temperature of -30 -35 by blast freezing or fluidized bed freezing. The packaging is made of polyethylene plastic bags or plastic boxes, which are divided into two kinds of packaging before quick-freezing and packaging after quick-freezing, generally using dry packaging, but 2% salt water can also be added to the packaging before quick-freezing for wet packaging, such as quick-freezing processing of mushrooms.

Is it the kind that is planted?

If you don't plant much, you don't have to do the work of keeping warm.

Morning and evening drenching will do.

When it grows, you can pick it and eat it.

1. Defrost at room temperature.

This is a relatively simple method, but it will take a lot of time. First of all, we take out the frozen food, such as pork, put it in a bowl or plate, let it stay at room temperature for about 2 hours, and it will be able to thaw on its own. If we want to cook it, we need to defrost it in advance.

After the thawing is completed, the shed needs to be washed with water to remove excess blood.

2. Defrost with hot water.

The reason why food freezes is because the temperature is too low, so another way for us to thaw is to thaw it with hot water. Put warm water in a container in advance, and then put the frozen food in it later, and it will be completely thawed in about 10-20 minutes, of course, you can also use warm or cold water, but this will be more time-consuming.

3. Defrost the refrigerator.

As we all know, there are two ways to preserve food, one is refrigeration, the other is freezing, generally vegetables will be placed in the refrigerator, if the meat needs to be thawed, we can put it in the refrigerator a day in advance, so that the next day it will become soft, and you can start making it after washing.

4. Heat and thaw.

In addition to being able to be defrosted with hot water, we can also use the cooking method to defrost, that is, to heat frozen food. Add a small amount of water to the pot, then put the frozen food in it and cook for a few minutes. However, it should be noted that high heat should not be used in the cooking process, because we have very little water, and if the fire is too large, the food will be cooked rotten, and the temperature is too high, which will also cause the nutrients in the food to be lost.

5. Defrost in the microwave.

Frozen food can be thawed directly in the microwave after removing the outer packaging, but it should be noted that if it is defrosted in the microwave, the food should not be left for too long.

6. Defrost with cold water.

This last method can be said to be the most common, and it is also the freezing method that most people will choose. First of all, we prepare a bowl of cold water, the temperature is about 4-8 degrees, and then take out the frozen food and put it in the bowl, the water is best to cover the food, so that it can be thawed quickly, about half an hour or so.

For plants, the nutrition is sufficient, the growth is good, the basic frost resistance of the cuticle thickening of leaves and fruits is very good, most of the antifreeze products on the market are composed of amino acids, medium and trace elements, these formula combinations, if the plant can really absorb and transform the utilization, can generally improve the frost resistance of the plant, so we mainly look at the absorption and utilization and the combination of the main ingredients when we choose.

Regarding the absorption and utilization, the light time in winter is short and the temperature is relatively low, the growth vitality of plants will also decline, so we use a lot of fertilizers with less plant absorption and utilization, which is why some antifreeze products work very well after use, and some do not work The main reason is that in fact, the feedback of the product effect is also the solution of product technology and problems.

For winter antifreeze products, it is recommended that you use foliar fertilizer that can solve the problem of low absorption and utilization caused by low temperature and short light factors, organic acid boron-calcium-molybdenum foliar fertilizer is this kind of fertilizer, rich in amino acids, boron-calcium-molybdenum and other elements, and the use of organic acid complexation technology, can improve the absorption and utilization of these elements by plants in the case of low temperature and low light.

In addition, there is a measure, that is, the use of photosynthetic bacteria and selenium-rich photosynthetic biological selenium foliar fertilizer, because of the presence of photosynthetic bacteria, can improve the photosynthesis of plants, supplement selenium-rich and organic nutrients contained in themselves, improve the plant's own resistance to stress, but also promote the plant root system is strong, flowering and fruiting is of good quality.

1. Skillful application of fertilizer, fertile soil and root protection, and increasing organic fertilizer before frost damage can enhance soil insulation performance and improve the frost resistance of vegetables. If it can be combined with available phosphorus and potassium fertilizer, the antifreeze effect will be better.

2. The part of vegetables that is most susceptible to frost damage is the root and whisker pith. Before mid-December, when the weather is fine, 1500 kg of livestock and poultry manure per mu can be mixed with soil and evenly cultivated in the roots of vegetable seedlings to prevent frost damage. Be sure to pay attention to the manure that has been fully rotted so as not to burn the vegetable seedlings.

Onions, spring cabbage, spring lettuce, mustard greens for stems, cabbage, etc., should be watered as little as possible before wintering, but seedling fertilizer should be applied 1 or 2 times. Before the ground freezes, it is best to apply manure once and cultivate the soil to prevent cold.

3. Timely winter irrigation, water and air are larger than heat capacity, before the invasion of cold snaps, timely irrigation while the weather is clear, which is conducive to soil absorption of water, storage of heat, and reduction of frost damage. After the cold snap, winter irrigation can be done in time when the weather warms up and the soil and vegetable roots thaw, which can timely improve the moisture required for the growth of vegetables, which is conducive to the healing of wounds of injured tissues and reduces the degree of frost damage. The amount of winter irrigation should be completely infiltrated on the same day, and after the clay is watered, sprinkle with a layer of fine soil or pig manure to avoid soil cracking and keep warm.

4. Cover the cold protection, before the severe winter, cover the vegetable seedlings with wheat straw, corn straw and other materials, which can not only reduce the cold wind damage near the ground, but also make the frost condense, release heat, and reduce frost damage. However, the amount of coverage is not easy to be too much, only a very thin layer is needed, and there is a certain amount of light transmission space. The general mulching is 100 200 kg per 667 square metres.

After the soil thaws in spring, the covering grass should be removed in time so as not to affect the growth of vegetables.

5. It can also be covered with a layer of plastic film at the seedling stage of vegetables, so that the thermal insulation effect will be better. When planting peas encounters cold winter weather, medium and small arch sheds can be erected in the field, covered with film and covered with straw curtains. In case of continuous rain and snow, cover double membranes and double curtains throughout the day, but it is necessary to open the curtains to receive light, pay attention to ventilation, and sprinkle dry fine soil on the furrow surface in time to avoid soil moisture and water droplets in the membrane.

Ventilation, sprinkling, and loosening of soil have a significant effect on disease prevention.

Vegetables are not afraid of freezing.

If you mean fresh vegetables that have just been picked from the vegetable patch, fresh vegetables are definitely more nutritious than frozen vegetables. But in fact, most of the vegetables we eat are not so fresh, and they are usually stored for a few days, and their vitamins are gradually lost in the process of storage.

1. Slice or tear the mushrooms into your favorite size after washing, blanch them in boiling water for 1-2 minutes, squeeze out the water after cooling, and store them in separate packages and freezers. 2. Wash spinach and other green leaves, scald them with boiling water, quickly remove them and put them in cold water to cool down, squeeze out the water, and then put them in a fresh-keeping bag for frozen storage. 3. Peel the corn directly and wrap it individually or cut it into sections and freeze it, and cook it directly in the pot without thawing when eating.

2. Wash spinach and other green leaves, scald it with boiling water, quickly remove it and put it in cold water to cool down, squeeze out the water, and then put it in a fresh-keeping bag for frozen storage.

3. Corn can be directly peeled, wrapped individually or cut into sections and frozen, and it can be boiled and eaten directly without thawing when eating.

4. Wash and drain the tomatoes, wrap them in plastic wrap or plastic wrap bags and freeze them. Frozen tomatoes are eaten in the same way as fresh tomatoes, peeled, cut and stir-fried.

5. After cleaning, cut the celery into sections, cut the broccoli into small flowers, and slice the zucchini, blanch the cut vegetables with boiling water (broccoli with salt), quickly take them out and put them in cold water to cool down, dry the water, pack and freeze them, and thaw them at room temperature when eating.

6. Beibei pumpkin can be washed and dried and frozen directly, but I recommend that no matter the size of the pumpkin, it should be washed, peeled and cut into small pieces, packed and frozen, and it will be very convenient to eat later.

7. Wash and dry the onion and green peppers, cut them into thin strips or small pieces, put them in a fresh-keeping bag and spread them flat, press out the air in the bag and seal them, which can be stored for one month.

8. Wash and peel the carrots and potatoes, cut them into slices or pieces, blanch them in boiling water for 1-2 minutes, cool them and freeze them in a fresh-keeping bag. When eating, thaw at room temperature and carry out normal cooking operations.

9. Wash, peel and cut the purple sweet potato, sweet potato and taro, steam it in a pot for about 15 minutes, let it cool, and then divide and freeze. (Be careful not to over-steam) It is usually suitable for cooking porridge.

1. Scientific fertilization.

Increase the application of organic fertilizer, promote soil looseness, increase ground temperature, increase soil insulation capacity, cooperate with the application of chemical fertilizers to control nitrogen and increase phosphorus and potassium fertilizer, promote root development, and enhance cold resistance.

2. Strengthen field management.

Before the occurrence of low temperature frost damage, combined with cultivating soil and fertilization, generally from late November to late December, human and livestock manure can be cultivated with soil in the roots of vegetable seedlings, which can not only prevent cold, but also improve soil temperature and protect roots.

3. Cover the cold.

Before the arrival of low-temperature frost damage, each mu should be evenly covered with straw or plastic film on the vegetable furrow and vegetables to prevent frost damage. However, it should not be covered too tightly so as not to affect the light and affect the growth of vegetables.

4. Irrigation and anti-freezing.

Watering on a sunny day before a cold snap arrives is good for the soil to absorb and store heat, so that the soil temperature does not drop too low.

5. Set up a windshield wall.

A windshield wall with plant straw or plastic film can be set up in the northwest direction of the vegetable field, which can play a role in keeping warm and anti-freezing.

6. Smoke and antifreeze.

Before frost damage is approaching, smoke with straw around the field to prevent it.

7. Harvest ripe vegetables in time.

**The Meteorological Observatory continues to issue a blue warning for heavy snowfall, how to prevent frost damage from vegetables in the open field?

Okay, that's all for what I'm going to share with you today, there will be blizzard weather in many places next, so farmers who grow open-field vegetables need to do some anti-freeze damage work now, and friends who don't know can learn from the anti-freeze damage measures shared with you! If you think this article is good, collect it!

Do sunny furrows. Vegetable furrows are more sunny to absorb sunlight. In winter, it is best to plant vegetables thicker and deeper, and plant them in a sheltered ditch.

Control watering. It is strictly forbidden to water during the low temperature period before the arrival of rain and snow, so as not to reduce the ground temperature and aggravate cold damage and frost damage. It is necessary to achieve "three watering and three non-watering", that is, watering on sunny days and not watering on cloudy days; Watering before the afternoon and not in the afternoon; Water little, not large.

Increase fertilizer application. Organic fertilizer is mainly applied to promote soil loosening and enhance soil thermal insulation. At the same time of applying sufficient organic fertilizer, it is necessary to use some available phosphorus and potassium fertilizer. Do not use fast-acting nitrogen fertilizers before the cold arrives.

Cover against the cold. The frost damage of vegetables is mainly caused by wind chill, frost damage, dry freezing and low temperature. Before the severe winter comes, cover the vegetable seedlings with wheat straw, straw, corn stalks and other materials, and only need to cover a thin layer to reduce the wind damage near the ground, and also make the frost condense, release heat, and reduce frost damage.

Set up barriers to block the wind. In the north of the vegetable furrow, use straw or film to make a meter-high wind barrier, and set up one every 2-3 furrows, which can also play a role in cold protection and warmth.

Dehumidification and stain reduction. In winter, the groundwater level is high, in case of rain and snow, soil moisture increases, and vegetables in the field, especially vegetables in the open field, are prone to roots, dead seedlings, and rotten vegetables.

Strong plants. Before the cold snap, rain and snow come, foliar sprays such as chitin and alginic acid can be applied with full-nutrient foliar fertilizers and plant-derived growth regulators. Before cooling, the water-soluble fertilizer of fruits and vegetables can be diluted 800 times and sprayed on the leaves, which can effectively supplement the nutrients of vegetables and improve frost resistance.