Vegetables contain starch, but starch can't be sweet. When the temperature drops in winter, these starches in vegetables will be hydrolyzed under the action of amylase and become maltose, and maltose will become glucose under the action of maltase, and glucose is sweet.

The following four vegetables taste better after frosting:

1, radish

Some radishes taste a little spicy before frosting, but they will become brittle and sweet after frosting. Interested friends can try it. The radish planted around September is edible at this time, although the radish has not reached the maximum. After frosting, let them continue to grow until it is going to snow, harvest them, and then put them in the cellar, or bury them directly in the soil, when to eat and when to dig.

2.cabbage

We often put radish and cabbage together, saying that cabbage tastes different after frosting, and its leaves are sweeter than before frosting. According to my personal taste, the frosted cabbage likes to eat the leaves outside after peeling off the outer layer, and the core of the cabbage will have a different taste.

3. Spinach

Spinach planted in August-September will be sweeter than before, and some people are not used to it. One of the reasons is that it will be bitter, but the bitterness of spinach planted in June 5438+10 will be weakened, especially in the roots, but it will not be eaten until years later.

4. mustard

Mustard planted in August-September can also be eaten in late June, 65438+ 10, which is similar to some vegetables. After frosting, the leaves will become sweet and the bitterness will be much reduced.

It is common that the sweetness of the above four vegetables will increase after frosting. In addition, there are other green vegetables, and there will be a similar situation. Then some friends will ask, why do some vegetables become sweet after frosting?

Strictly speaking, after a series of reactions, the glucose content in vegetables increases, thus increasing the sweetness. Vegetables contain more starch, but the sweetness of starch is not obvious. After the first frost, the weather turns cold and the vegetables themselves will change. The starch contained in it will be converted into glucose through a series of reactions such as hydrolysis under the action of amylase, so the sweetness will increase.

However, not all vegetables will become more delicious after frosting, and not all vegetables can be eaten after frosting. For example, there are many sayings about frost eggplant. Some people say that frosted eggplant tastes sweeter, and some people say that frosted eggplant can't be eaten, because after frosting, the water content of eggplant will decrease and solanine will increase. If overused, it will cause discomfort.

In addition, it should be noted that there is a certain difference between falling frost and frost. It is normal for first frost that the vegetables mentioned above will become delicious after frosting. However, if frost occurs, it will affect the normal growth of crops and lead to reduced production. Frost will destroy the cells of vegetables and cause the seedlings to die at low temperature for a long time.