After the potatoes are shredded, the iron inside will be oxidized to iron oxide when exposed to the air, and the iron oxide is reddish brown, so the potatoes will turn red after being shredded for a period of time.

In order to prevent the shredded potato from turning red, it can be put into water (preferably light salt water) after shredding, but it should not be soaked for too long, because the nutrients will be lost after soaking for a long time.

The result of starch oxidation in potato is that there are phenols in potato to maintain its respiration.

When potatoes are peeled, phenols in plant cells are combined with oxidation in the air under the action of phenolase, resulting in a large number of quinones.

Neoquinones can make plant cells turn brown quickly, which is called enzymatic browning of food.

So potatoes will change color after peeling for a period of time.

Not only potatoes, but also some vegetables.

Browning affects the appearance of food and reduces the nutrients in the outer layer, but it is still edible.

If potatoes are peeled for a long time, the oxidative decomposition of plant cells in the air will be intensified, and the nutrients in the outer layer of potatoes will be decomposed more, and pectin will be further decomposed into pectin acid and methanol under the action of enzymes, which will make the pulp loose, wet, discolored, stale and even rotten.

According to the nutritionist's point of view, potatoes should be peeled and eaten, and the parts with bud eyes should be dug to avoid poisoning.

It is normal that potatoes are easy to oxidize and turn black after being cut, because there is a lot of starch on the surface, which will turn the color of potatoes red and black in the air, but it will not cause harm to the human body, but this kind of potatoes is also easy to stick to the pot when fried, and the taste is not good.

Because there are phenols in potatoes, it is the result of maintaining their respiration.

When potatoes are peeled, phenols in plant cells are combined with oxidation in the air under the action of phenolase, resulting in a large number of quinones.

Neoquinones can make plant cells turn brown quickly, which is called enzymatic browning of food.

So apples will change color after peeling for a period of time.

Not only potatoes, but also some vegetables.

Browning affects the appearance of food and reduces the nutrients in the outer layer, but it is still edible.

If potatoes are peeled for a long time, the oxidative decomposition of plant cells in the air will be intensified, and the nutrients in the outer layer of potatoes will be decomposed more, and pectin will be further decomposed into pectin acid and methanol under the action of enzymes, which will make the pulp loose, wet, discolored, stale and even rotten.

Mainly because there are three main conditions for the occurrence of oxidative browning of starch: polyphenols, polyphenol oxidase and oxygen.

After peeling potatoes, they are exposed to the air, and the polyphenols in them react with oxygen to generate o-quinone, which is further oxidized and polymerized into brown pigment and melanin.

This situation is not uncommon in real life, such as apples, eggplant, lotus roots and so on. After peeling, enzymatic browning will lead to darker color. How to prevent peeled potatoes from discoloring: 1. Soaking method If peeled potatoes and other fruits and vegetables that are easy to change color are soaked in cold water to isolate oxygen in the air, they will not change color.

2. The activity of acid-added phenol oxidase is the strongest when the ph value is 6-7, and it will decrease when the ph value is less than 3.

Therefore, adding vinegar to food to reduce the ph value can inhibit the activity of enzymes and slow down the speed of discoloration.

The starch in potatoes has a chemical reaction. 1. The reasons why potatoes turn red are as follows. First, the reason for turning red:

Potatoes contain iron.

After the potatoes are shredded, the iron inside will be oxidized to iron oxide when exposed to the air, and the iron oxide is reddish brown, so the potatoes will turn red after being shredded for a period of time.

The price of iron in potatoes has changed from bivalent iron to trivalent iron.

Secondly, there is an enzyme called polyphenol oxidase in the vacuole of many plants, including potatoes, which can react with some substances in cells and turn red. However, when the cells are intact, this reaction cannot occur because of the protection of vacuole membrane. In the process of shredding potatoes, cells are destroyed and can react to make them turn red. There are many other examples. For example, after an apple is bitten, the bitten place will turn red after a period of time.

With the increase of reaction amount, the color will gradually deepen and finally become dark brown.

The oxidation reaction is due to contact with oxygen in the air, and phenol oxidase is released from cells.

Second, the solution: when just cut, the soaked water will not change color, and the soaked starch will be less. Phenols in cells will combine with oxygen in the air and turn red. This is because potatoes contain starch, which will turn red in a short time after peeling.

After peeling potatoes, phenolic compounds in plant cells combine with oxidation in the air under the action of phenolase to produce a large number of quinones.

Neoquinones can make plant cells turn brown quickly, which is called enzymatic browning of food.

So apples will change color after peeling for a period of time.

Not only potatoes, but also some vegetables.

Browning affects the appearance of food and reduces the nutrients in the outer layer, but it is still edible.

If potatoes are peeled for a long time, the oxidative decomposition of plant cells in the air will be intensified, and the nutrients in the outer layer of potatoes will be decomposed more, and pectin will be further decomposed into pectin acid and methanol under the action of enzymes, which will make the pulp loose, wet, discolored and stale, and even rotten potatoes will be oxidized when exposed to air. This is because there are phenols in potatoes to maintain their respiratory function.

When potatoes are peeled, phenols in plant cells are combined with oxidation in the air under the action of phenolase, resulting in a large number of quinones.

Neoquinones can make plant cells turn brown quickly, which is called enzymatic browning of food.

So apples will change color after peeling for a period of time.

Not only potatoes, but also some vegetables.

Browning affects the appearance of food and reduces the nutrients in the outer layer, but it is still edible.

If potatoes are peeled for a long time, the oxidative decomposition of plant cells in the air will be intensified, and the nutrients in the outer layer of potatoes will be decomposed more, and pectin will be further decomposed into pectin acid and methanol under the action of enzymes, which will make the pulp loose, wet, discolored, stale and even rotten.

Therefore, it is best to eat it immediately after peeling.

The simple way to control the discoloration of potatoes is to immediately soak peeled potatoes in cold boiled water, sugar water or light salt water to isolate them from the air and prevent the oxidation of phenolic substances in plant cells.

However, from the perspective of preserving the nutrients in potatoes, peeled potatoes should not be soaked for too long.

Under the action of enzymes, the oxidation reaction discolors the potato, which is the result of maintaining its respiration because it contains phenols.

When potatoes are peeled, phenols in plant cells are combined with oxidation in the air under the action of phenolase, resulting in a large number of quinones.

Neoquinones can make plant cells turn brown quickly, which is called enzymatic browning of food.

So apples will change color after peeling for a period of time.

Not only potatoes, but also some vegetables.

Browning affects the appearance of food and reduces the nutrients in the outer layer, but it is still edible.

If potatoes are peeled for a long time, the oxidative decomposition of plant cells in the air will be intensified, and the nutrients in the outer layer of potatoes will be decomposed more, and pectin will be further decomposed into pectin acid and methanol under the action of enzymes, which will make the pulp loose, wet, discolored, stale and even rotten.

This is because there are phenols in potatoes to maintain their respiration. When potatoes are peeled, phenols in plant cells are oxidized by air under the action of phenolase, and a large number of quinones are produced.

Neoquinones can make plant cells turn brown quickly, which is called enzymatic browning of food.

So apples will change color after peeling for a period of time.

Not only potatoes, but also some vegetables.

Browning affects the appearance of food and reduces the nutrients in the outer layer, but it is still edible.

If potatoes are peeled for a long time, the oxidative decomposition of plant cells in the air will be intensified, and the nutrients in the outer layer of potatoes will be decomposed more, and pectin will be further decomposed into pectin acid and methanol under the action of enzymes, which will make the pulp loose, wet, discolored, stale and even rotten.

Therefore, it is best to eat it immediately after peeling.

The simple way to control the discoloration of potatoes is to immediately soak peeled potatoes in cold boiled water, sugar water or light salt water to isolate them from the air and prevent the oxidation of phenolic substances in plant cells.

However, from the perspective of preserving the nutrients in potatoes, peeled potatoes should not be soaked for too long.

Because the phenols in potatoes will be oxidized when they come into contact with air, they will not do harm to health. When used to cut potatoes, phenols in damaged potato cells will be oxidized by air under the action of phenolase, producing a large number of quinones.

Newborn quinones can quickly turn plant cells into reddish brown, which is called enzymatic browning of food. Although this affects the appearance of food and reduces the nutrients in the outer layer, it is still edible. If you want to control the discoloration of potatoes, you only need to control them to be isolated from the air, such as soaking them in cold boiled water, sugar water or light salt water. Of course, potatoes should be eaten as soon as possible after being cut.

Potatoes contain phenols, which is the result of maintaining their respiration. This is because there are phenols in potatoes, which is the result of maintaining their respiration.

When potatoes are peeled, phenols in plant cells are combined with oxidation in the air under the action of phenolase, resulting in a large number of quinones.

Neoquinones can make plant cells turn brown quickly, which is called enzymatic browning of food.

So apples will change color after peeling for a period of time.

Not only potatoes, but also some vegetables.

Browning affects the appearance of food and reduces the nutrients in the outer layer, but it is still edible.

If potatoes are peeled for a long time, the oxidative decomposition of plant cells in the air will be intensified, and the nutrients in the outer layer of potatoes will be decomposed more, and pectin will be further decomposed into pectin acid and methanol under the action of enzymes, which will make the pulp loose, wet, discolored, stale and even rotten.