Potato has long been a leader in the everyday and festive table. It is served as an independent dish and is used as an ingredient. In order for the side dish to have an appetizing appearance, you need to know why the potatoes turn black after cooking and what needs to be done to avoid this.
How to cook potatoes?
The product must be washed and cleaned before cooking. It is better to put a potato in salty and hot water, but not in cold. So the product will save more vitamins and nutrients. The liquid in which the potatoes were cooked can be used to cook vegetarian soups and decoctions.
If you cook "in uniform", then the dish will be much more useful. But it should be borne in mind that on the surface of tubers and in the peel there is solanine glycoside - this is a poisonous and bitter substance. If the potato has sprouted, then it must be thoroughly peeled. In the event that the product grows in fertilized soils, after cleaning it should be kept in cold water for about half an hour.
Why is potato getting dark?
Probably, every housewife thought about why the boiled potatoes were turning black. The reason for this is of a chemical nature. The tubers contain the amino acid tyrosine, which begins to oxidize and form the pigment melanin. It is he who paints the potatoes in a dark color.
On an industrial scale, this problem is solved with the help of sulfur dioxide (sulfur dioxide), which process the product. This substance has reducing properties. At home, potatoes can be dipped in boiled water and covered with a lid to prevent oxygen from entering.
How to avoid excessive softness of potatoes?
When boiling, the potato becomes soft due to the fact that the polymer molecules of protopectin are destroyed and are transferred to the molecule of pectin, which is soluble. At the same time, magnesium and calcium cations are removed from the tubers. If the water is hard, then this process is much slower. Therefore, potatoes must be laid in dishes earlier than sour seasonings and products, otherwise it will remain undigested and tough.
How to determine which potato will turn black?
In trying to find the answer to the question of why the potatoes turn black after cooking, you need to have an idea of the cause of this phenomenon. Darkening after cooking is different from that formed on the raw product. There is a method that allows you to determine which tubers will turn black. To do this, treat the potatoes with a solution of sodium nitrate, to which diluted hydrochloric acid is added, and then grease with sodium hydroxide. Within a few minutes, the treated area will begin to turn red.
Is darkened potato dangerous?
The housewives are interested not only in why the potatoes turn black during cooking, but also whether it is dangerous to health. Experts say that such a product can be safely eaten.
Gardeners recommend observing the correct proportions of fertilizers. The synthesis may be disturbed if there is a large amount of nitrogen, but not enough potassium. This will lead to the accumulation of proteins and amino acids. Therefore, it is worth taking care of a sufficient amount of potassium.
To avoid darkening, you need to keep the potatoes until frost in a dry and cool place. Then the tubers will have time to dry and cool. If you immediately place the product in the basement, then physiological changes will occur and the tubers will darken during cooking. In the case when it is impossible to do this for some reason, it is necessary to hold the potatoes before cooking for some time in cold water.
Storage and ventilation
To understand why potatoes turn black after cooking, it will be useful to find out the rules for storing it. Darkening can be caused not only by over-compacted soil, but also by insufficient ventilation during storage. This leads to the fact that the potato is not enough air, and it begins to “suffocate”. To avoid this, it is necessary to regularly ventilate the room and carefully inspect the vegetables that are there. Do not store foods that have begun to rot or have damage.
Temperature and humidity also matter. Perspiration can cause rapid growth of mold, which absorbs oxygen. All wet tubers should be thoroughly dried.
Harvesting and transportation
The answer to the question of why potatoes turn black after cooking can be a failure to comply with the rules of harvesting and transportation. When collecting potatoes, you must not drop it and allow it to be damaged. During storage, it is very important to ensure that conditions are always optimal.
How to cook frozen potatoes?
If the product is frozen, it must be defrosted in cold water. When an ice crust forms around the potato, you need to change it and add a little salt.
To make it easier to peel the potatoes “in their uniforms”, after boiling it is necessary to pour them with cold water.
The secrets of cooking boiled potatoes
Experienced culinary experts advise adding a little vinegar to the water during potato cooking. This will not only prevent darkening, but will also help ensure that the product does not fall apart.
Jacketed potatoes will not boil if a little more salt is added than is required during conventional cooking.
Those varieties of potatoes that are considered powdery are often very boiled, so you should add brine from cucumbers or cabbage to the water, and then a little more vinegar. It is better to cook such a product on low heat so that the starch swells evenly.
One explanation for why boiled potatoes are blackening may be that it is "old." In this case, a small amount of milk can be added during cooking.
If potatoes are not cooked immediately after cleaning, it is better to keep them in cold water, in which a drop of vinegar is added. It should be salted at the beginning of cooking, so more vitamins and useful components will be preserved.
Where to keep peeled potatoes?
We have already figured out why the potatoes turn black after peeling. This is due to the fact that the compounds contained in the product interact with air, and this, in turn, causes the oxidation process. This can be avoided by pouring root vegetables with water and vinegar.