Dark spots appeared when the potatoes were cooked. Why do peeled potatoes darken?

Why potatoes turn black inside during storage - there are a lot of reasons for this, from the choice of variety to the conditions for keeping it in the cellar. Experienced gardeners, having learned from their mistakes, follow all the necessary rules. When creating the right conditions for storage, potatoes are able to lie almost until the next harvest.

Why do potatoes turn black inside

Potato is a very popular vegetable in Russia; almost every gardener grows it. But it is important not only to get a big harvest, but also to keep it. The most common problem in this case is that the tubers turn black inside. Sometimes even normal-looking vegetables have dark spots in the cut.

Important! Medium-sized mature tubers are stored the longest.

It is necessary to timely identify the reason why the tubers begin to turn black inside during storage and eliminate it, otherwise the entire crop may be destroyed. Such signs can be caused by both the physiological disease melanosis or, in other words, gray spotting, and various infectious diseases caused by fungi.

Adverse weather conditions

Potatoes grow well in moderate humidity and temperature. If these indicators change, then this negatively affects the yield and keeping quality of tubers:

at high temperatures, the vegetable overheats;
at low temperatures, potatoes grow small due to a lack of nutrients;
with a lack of watering, the culture dries up;
with an excess of moisture, oxygen is poorly supplied to the tubers, provoking the development of bacterial and fungal infections.

All these conditions, individually or in combination, can lead to the fact that the vegetable begins to turn black inside. Thus, the product loses its consumer qualities.

Incorrect fertilization

Some gardeners, in pursuit of large yields, fertilize the vegetable crop with too much organic matter. Herbal infusions, manure or green manure are used. These fertilizers promote plant growth due to the high nitrogen content. But during storage, such overfed tubers begin to turn black inside.

To avoid damage to potatoes after harvest, you need to fertilize it according to the rules:

fresh organic fertilizers are not used, only rotted ones;
manure is rarely applied - 1 time in 2 years.

Often there is an excess of nitrogen and a lack of potash fertilizers in the soil. Namely, potassium just contributes to the long-term storage of potatoes. Without it, it may begin to turn black.

Mechanical damage to tubers

Potatoes can also turn black inside due to mechanical damage that occurs during harvesting or transportation. Deformed parts of the potato subsequently change color. And if the skin is damaged, then there is a high risk of penetration of fungi and bacteria into the vegetable.

Potatoes also turn black inside during storage when they are placed in several layers. The tubers lying below experience quite a lot of pressure.

infectious diseases

The appearance of characteristic dark spots inside the tubers is usually accompanied by diseases such as:

Blackleg. A disease called black leg affects the tops and tubers of potatoes. Its first symptoms appear during storage of the crop. It is a rot that reaches the center of the tubers inside, and they begin to turn black. Outwardly, it can be distinguished from gray spotting. The whole fetus is affected, starting to exude an unpleasant odor. Nearby potatoes are also susceptible to infection. It is important to identify the disease at the growing stage in order to prevent such vegetables from entering the store.

Late blight. The disease is common in almost any climatic conditions where potatoes are grown. Both tops and tubers are affected. The fungus spreads rapidly, damaging all plants. Brown spots appear on the leaves, they rot and dry out. The disease is transmitted through weeds, progresses in violation of the agricultural technology of potato cultivation. Tubers affected by phytophthora are covered with brown spots from the inside. The development of the fungus is promoted by high temperature. Potatoes become infected during harvesting or from their own diseased tops. The probability of transmission from a neighboring tuber during storage is minimal. Late blight can also provoke diseases by other fungi.

Improper storage

Storage of potato harvest is carried out in the basement with a temperature of +1 to +4 °C. If the indicator drops below, then the tubers become sweet and begin to turn black inside. At higher temperatures, potatoes germinate and the risk of gray rot increases.

Late cleaning

Timely harvesting of potatoes is a guarantee of preserving the resulting crop. To prevent the tubers from turning black inside, adhere to the following rules:

When harvesting potatoes, one must be guided by varietal characteristics - a crop harvested too early is likely to turn black inside during storage. Tubers should ripen in natural conditions.
Harvesting must be done before the first frost. If you leave potatoes in the ground at temperatures from -1 ° C, they will freeze and then rot during storage.
After the tops have been mowed, the tubers must be harvested as soon as possible. If warm weather begins, the vegetable may overheat.
Harvested potatoes are stored in a dry, well-ventilated room at a temperature of +4 °C.

Harvesting potatoes in a timely manner reduces the likelihood that the tubers will begin to blacken inside during storage.

What to do so that the potatoes do not turn black

Very often situations arise when potatoes have lain in the basement all winter, and by spring they begin to turn black. This could be due to poor ventilation.

With warming, the potatoes go into storage and germinate. The flesh darkens and becomes sluggish. There is a sharp jump in temperature, the release of moisture and the debate continues. Thus, you can lose the entire crop.

To prevent the potatoes from turning black inside during storage, a number of rules must be observed:

after harvesting within 20 days, the potatoes should be located in the fresh air;
place it in wooden boxes equipped with ventilation holes;
maintain the required temperature in the storage;
boxes and pallets should be moved away from the walls by 20 cm;
potatoes are sorted at least once - germinated and diseased tubers are removed, as well as healthy ones located next to them;
if storage is carried out at home on the balcony, then the boxes are recommended to be covered with a warm blanket;
potatoes can only be stored together with beets, which will take away excess moisture from it; proximity to other vegetables is strictly prohibited.

Is it possible to eat darkened potatoes

If the potato turned black inside from rot, with infectious diseases, then it should not be eaten. In other cases, eating such tubers is allowed, but they lose their useful properties and taste. They are low in vitamins, protein and starch. Dishes from such potatoes look unattractive, so tubers with black spots are not eaten.

Storage rules

How long the potatoes will lie depends on the proper preparation for storage and the conditions in the cellar itself. The choice of variety during planting also affects. The main factors that must be considered for the preservation of the crop:

When planting, you need to think about which varieties will be needed, because they are stored in different ways. Late potatoes are intended for long-term storage in the cellar. Early varieties, even under ideal conditions, will not last long. They are meant to be eaten directly in season.
Before being sent for storage, the tubers are sorted and sorted - diseased, damaged, and suspicious ones are removed. Potatoes in contact with diseased vegetables should also be removed, they may be infected, but the symptoms have not yet appeared. Even a few diseased tubers can ruin an entire crop in storage. Potatoes must be dried, otherwise raw tubers may turn black inside and rot.
It is necessary to constantly monitor the temperature at the place of storage of the crop. Special control is needed during the change of seasons in autumn and winter, when there is a risk of temperature fluctuations.

Important! Some varieties of potatoes contain a lot of starch and a slight browning is normal for them.

To maintain the desired air temperature in the storage, ventilation is used, bottles of cold or hot water are placed around the perimeter of the cellar. Thus, the risk that the vegetable begins to blacken inside is reduced. With timely monitoring of indicators of humidity and temperature, potatoes can be preserved.

Conclusion

There are many reasons why potatoes turn black inside during storage. If you choose the right variety, observe the regime of watering and top dressing, then such a nuisance can be avoided. It is also worth harvesting, guided by the rules available for this. The final and one of the main points in the safety of tubers are the conditions for their maintenance in the cellar.

Potato is the most popular crop in Russia. It grows in every garden, and with the advent of autumn it is removed to the cellars for long-term storage. But, unfortunately, it happens that potato tubers begin to turn black. The most common reason for this process is improper storage. Let's see why this happens and what to do if the seedlings have time to freeze.

Even seemingly healthy vegetables can have black spots. Why this happens is often a mystery. If this problem has spread to a large part of the crop, urgent action must be taken.

What varieties can be stored in winter

There are about 380 varieties of potatoes. All differ in skin color, pulp, taste, root size, ripening time. When choosing potatoes for long-term storage, you need to be guided by another indicator - its keeping quality.

Potato storage is directly affected by the selected variety based on the ripening time. The most unsuitable variety is early ripe, such a vegetable is intended for consumption in summer and at the beginning of autumn maximum. Varieties with medium and late ripening are suitable for long-term storage.

When choosing a term, you need to look so that the technical maturity of the root crop reaches 100-130 days. Such a potato forms a thick peel, copes well with diseases, contains a large amount of tannins.

It is better to purchase several varieties of potatoes if there is no experience in planting and storing a certain type of root crop.

Late varieties for long storage most suitable. They contain a large number of microelements and will last until spring without problems. Popular late varieties: "Picasso", "", "Lorch", "Atlant", "Vesnyanka".

Desired temperature and humidity for potatoes

The vegetable should be stored at a temperature +2 +6 degrees and the air humidity should be 80-90% . The most suitable storage room is a cellar or basement.

Room ventilation required. At a temperature of 0-1 degrees, the potato does not rot, but becomes sweetish, and the flesh darkens. At a temperature of 7-12 degrees, the tubers begin to germinate, become soft, spots appear on the pulp.

Why do potatoes turn black inside during storage

Darkening can occur due to disease - gray spot.

The main causes of darkening:

culture dislikes fresh organics, as excess nitrogen is released, which contributes to the reproduction of fungi. This contributes to the browning of the potatoes;
at the origin of the root crop, there is a lack or excess of moisture;
the crop is harvested ahead of time, the flesh darkens in the unripe potatoes. Overripe potatoes, during the heat period, may deteriorate when stored in an overheated room;
if harvesting is done late in the frost period, the tubers may overheat, the flesh may darken. At a soil temperature of -2 degrees and frost, the tubers begin to rot;
poor-quality transportation: shocks, pressure;
improper storage conditions over a long period. The temperature is above or below 2-6 degrees;
tubers contain a high percentage of starch;
disease damage - blackleg. It is transmitted through planting material, continues to be affected by the disease and blackness during storage.

Why does it turn black in spring

It happens that the vegetable survived the winter well, and with the advent of spring it begins to turn black. The reason may be in poor ventilation.

Potatoes begin to rot with the advent of warming and germinate in the spring, the flesh darkens, it becomes lethargic and soft. There is a sharp temperature drop in the storage. Moisture is released and this again contributes to the debate.

What can and should be done so that the vegetable does not darken

So that the potatoes do not darken, you need to observe the temperature regime and store it in wooden boxes with ventilation holes.

Install pallets and move away from the walls by 20 cm. Thanks to this, you can avoid: getting wet and freezing.

After harvesting you need within 20 days leave the potatoes to ventilate in the fresh air. It is forbidden to store the root crop with other vegetables, except for beets.

During the frost

Sometimes it happens that a vegetable falls under frost. It's not entirely dangerous if the potatoes haven't risen. But if sprouts have appeared, then the arrival of frosts can affect the quality of the future crop and beat it.

Are colds terrible for culture?

spring frosts terrible for the harvest potatoes. This is especially true for the regions of Siberia. Young potato sprouts are afraid of frost and are especially sensitive to spring frosts, and any temperature from 0 and below can kill the crop.

Will potatoes go away on their own after freezing

Some gardeners plant potatoes as early as early March, and there is a risk that the crop will fall under frost.

If the young sprouts are frozen, then this may affect the future of the crop, although the potatoes will continue to grow with warming. Older plants are not affected much by the cold.

How to save after frost

If they promise frosts, you need to urgently spud seedlings crops, and after frosts release the bushes then the ridges.

To avoid freezing and give the potato a chance to survive if it has been frozen, you can warm the vegetable by covering the plantings with grass. Some gardeners make fires from straw, shavings along the edges of arable land and thereby insulate the soil. To increase the smoke mass, it is recommended to drop mineral oils or coal tar inside the fire. It is also possible cover beds with foil.

If the frosts have passed, and the vegetable has already managed to freeze, you need to allow the bushes to restore themselves on their own. Damaged bushes are able to recover, albeit with great effort. To help the crop, you need to feed it with nitrogen fertilizers.

The reasons that the potatoes in the garden are frozen

If the air temperature drops below zero degrees, or night frosts begin in the spring, the potatoes begin to freeze and may freeze. This affects the sprouts, they blacken and wither. In the future, even if the plants continue to grow and "move away", the flesh of the fruit may begin to turn black.

What to do if the shoots and tops had time to freeze

If the frosts began unexpectedly and the seedlings froze, then you need darken them before dawn with the help of: newspapers, dark film, rags.

The main thing is that thawing occurs gradually, then the tops will not wither and frostbite will be insignificant.

What to feed

Affected crop needs treatment nitrogen, and it is also necessary to make top dressing: nitrophoska 5 gr. per 1 sq.m.

Foliar top dressing with urea 20g per 10 liters of water is also useful. In order for the frozen tops to come to life, you need to spray it " Epinom Extra».

If the frosts began when the crop has faded, but it has not yet been harvested, then you can feed it with ash or potash preparations. After the cold weather, it is forbidden to dig potatoes, you need to wait for warming.

The first actions if frost hit after planting

If, after planting, they grabbed and hit frosts, the vegetable managed to freeze, then in order to save it, it is urgently necessary to reanimate and process it with special means.

Ways to save the crop if frost portends:

hilling. After frost, sprouts suffer, so the crop should be piled up so that the tops are completely under the crest;
mulching. Warm the crop with a thick layer of straw, hay or sawdust;
covering the crop with foil. Only the film should not put pressure on young shoots. Pegs should be installed around the perimeter and the film should be stretched;
sprinkling. The crop should be watered abundantly when t is 0. The water will begin to evaporate and protect the plant;
smoke warming. This method of frost protection was mentioned above. It is necessary to kindle a fire on both sides of the crop so that the smoke covers the entire area. To create a smoke screen, you need to kindle a fire so that the fire burns 50-70 cm in height. To do this, you can burn straw, firewood, manure. The fire should burn for 3-4 hours in the morning. The method is effective only in windy weather;
strengthening the immunity of culture. Even before planting the crop, planting material should be strengthened with growth regulator preparations. They help young sprouts to endure any weather conditions. The most popular: Silk, Biostim, Epin Extra.

To provide yourself and your family with potatoes for the whole winter, you need to choose the most "tenacious" potato variety, as well as follow the rules for storing root crops. Have a rich harvest!

According to experts, blackened potatoes do not pose any danger, so you can safely gobble them up on both cheeks. It is believed that this comes from an excess of mineral fertilizers and nitrates, but in fact there can be several reasons for this phenomenon at once: for example, the unusual composition of the soil, different varieties of potatoes, weather conditions, an excess of nitrogen against the background of a lack of potassium, and so on.

And although eating such a vegetable is not very pleasant, it can be safely planted, only in this case it is necessary to observe the correct proportions of fertilizers. So, if there is little potassium and a lot of nitrogen, synthesis will most likely be disturbed, which will lead to the accumulation of proteins and amino acids to the detriment of starch. So potassium is needed in sufficient amounts, as it stimulates the formation of carbohydrates, including starch. At the same time, an excess of potassium salts affects the plant - they contain a lot of chlorine, which has a harmful effect on potatoes, worsening its taste and reducing starch content.

But amateur gardeners expressed their version of the darkening of the vegetable. Before frosts begin, potatoes must be kept in a cool and dry place so that its tubers cool and dry. If this is not done and immediately placed in the basement, they will instantly supercool, which will lead to their physiological changes. As a result, such tubers darken during cooking. However, if they are put in cold water for several hours, this effect can be avoided.

“Potatoes always turn black during cooking if they have grown on overcompacted soil and if there is insufficient ventilation in the pit where they are stored, that is, the potatoes are suffocating from lack of oxygen. Another possible cause of blackening is a lack of potassium during growth. »

In fact, there are many reasons: an excess of nitrogen against the background of a lack of potassium, varietal differences in potatoes, weather conditions, the mechanical composition of the soil, etc.
If you make a lot of nitrogen and little potassium, then synthesis is disturbed, amino acids and proteins accumulate to the detriment of starch. Potassium stimulates the formation of carbohydrates, especially starch. Therefore, potash fertilizers must be applied under potatoes. But potassium salts contain a lot of chlorine, which easily penetrates the plant and has a harmful effect on it. In potatoes, starch content, taste, and keeping quality are reduced, so it is better to use potassium sulfate for potatoes. It does not contain chlorine, and sulfur is necessary for the formation of vegetable proteins. Chlorine-containing potash fertilizers (KCl) can only be applied for autumn digging. »

The fact is that in the process of growth, chlorogenic acid accumulates in potato tubers, which, during heat treatment, forms a strong dark compound with iron ions. In most cases, such a reaction is prevented by citric acid, for the formation of which potassium is responsible in the tubers. To eliminate this problem, chlorine-free, potash fertilizers are applied to the soil.

Choosing potatoes: for cooking, frying and storage

Starch content above 15% - the variety is suitable for mashed potatoes. Puree will be tender and lush, however, very high-calorie. Varieties: Blueberry, Lorch, Sineglazka, Lugovskoy, Adretta, Elizabeth.

Below 15% - for soup and salad. Such tubers do not fall apart during cooking, low-calorie: Leader, Handsome, Alvara, Red Scarlett, Nevsky, Luck, Nikulinsky. And the Gourmet variety - with dark blue flesh and a high content of antioxidants, is suitable for salads. It can even be eaten fresh.

Dry matter - at least 20-24%, and reducing sugars - no more than 0.5% - such potatoes can be fried, they will not crumble in a pan or in a deep fryer, they will not acquire a bitter taste and will not darken. These varieties have the ability to "keep" starch from breaking down into sugars. Thanks to this property, potato slices retain their shape during frying. Varieties: Leader, Nadezhda, Kolobok, Early Bryansk, Early Zhukovsky, Impala, Feloks

On a note

When cooking mashed potatoes, it is better to put the tubers in boiling water, and for salad - in cold water.

Until the water boils, some of the starch will be washed out of the “salad” potatoes, and it will not crumble.

Unwashed potatoes make it easier to choose

The best domestic potatoes grow in the Lipetsk, Voronezh, Kursk, Tambov, Tver regions, in the Moscow region. Potatoes do not like heat, because of it the quality of tubers decreases. Potatoes brought from the Bryansk, Leningrad regions and from the north of Ryazan must be chosen more meticulously. In these regions, there are both good and not quite suitable soils for potatoes, giving a product of not the best quality.

If you buy unwashed potatoes (these are the best for long-term storage), consider that you have a trump card: thanks to the earth adhering to the tubers, you can understand how the potatoes will be stored and how tasty they are.

The worst option is sand (hard grains of sand are felt). On the sand, the tuber is “liquid”, it is poorly stored, it darkens when cooked.

Potatoes from peatlands can suffer the same deficiencies if poorly cared for, but still to a lesser extent. You can recognize peat by its deep black color; when it dries, it almost does not brighten, crumbles, and is present on the skin of potatoes mainly in the form of dust.

It is easiest to grow good potatoes on chernozems and loams. When you see potatoes with black, gray or brownish plastic “dirt” stuck to the tubers, take it boldly.

Better than others, Lorch, Handsome, Golubyzna, Nikulinsky keep their “unblemished reputation”.

Signs of a good potato

1. Choose larger tubers. As a rule, they have time to ripen better, that is, they are tastier and have more vitamins.

2. Tubers are dense, hard.

3. The peel is smooth and without roughness, dark spots.

4. Eyes - clean, shallow, without a dark halo (a sign of decay)

5. Potatoes do not crack or split when cut.

Potatoes have long been recognized by scientists as one of the most useful plants for humans. Its tubers contain a variety of vitamins and minerals. Even if there is only a certain time of it, the condition of a person will not worsen from this. For many lovers of this root vegetable, there is only one problem - why the potato turns black after cooking, but otherwise, this is one of the most versatile foods.

The plant has long been considered a second bread for many peoples. People eat it daily, the list of national potato dishes is huge. Approves its use and modern medicine. Especially important is the fact that the tubers are high in potassium, which is beneficial to the heart and has a diuretic effect.

So that during growth the potato bush does not experience a deficiency of potassium and gives a good harvest, special fertilizers are applied to the soil. In autumn, without fail, chlorine-containing potash fertilizers are scattered on the site, then they are dug up before winter. If you need to improve the composition of the soil in the spring, then potassium sulfate is used for this.

If, on the site, the land is treated mainly with nitrogen fertilizers, do not add potash or make very little of them, which will not meet the required standards, then a violation of the synthesis of substances will certainly occur. As a result, amino acids accumulate in large quantities, and most importantly, tyrosine, which, when oxidized, produces melanin, which contributes to the fact that potatoes with its high content darken some time after peeling and cooking.

Based on the data obtained, it can be said that the darkening of potatoes during processing indicates that the proportions of fertilizers applied to plants were not respected during cultivation. Perhaps the soil was oversaturated with nitrogen and lacked potassium.

Refusing to eat potatoes just because they darken after peeling and boiling is not worth it. Indeed, for many, this is the main product on the table. But still it is worth taking into account some facts:

the darkening of potatoes indicates a violation of the rules for growing and storing;
the composition of the root crop has undergone a change, some of the useful properties have been lost;
you need to put a few bay leaves in a saucepan in which the potatoes are boiled, if after that the root crop has darkened, consider whether it is worth eating it.

A strong darkening indicates that the composition of nutrients in the tubers has changed significantly. Even if this did not affect the taste, such potatoes should not be eaten.

To have a tasty and healthy potato dish at dinner, you need to be able to choose it correctly. Even large tubers can have an unpleasant soapy taste after cooking and darken soon. Potatoes can have different flavors. It depends entirely on the variety. Potatoes containing a lot of starch are crumbly, have a short cooking time, and those with a low content are used mainly for frying.

A potato that meets all the requirements is elastic, and when its skin is torn, a soft crack is heard. Don't buy wet potatoes. Such tubers are grown in violation of technology or stored incorrectly. Most likely, the entire crop will quickly deteriorate.

You can not buy potatoes with green spots. This means that she was exposed to prolonged exposure to sunlight, corned beef was formed in her - a very toxic substance. In addition to the fact that the taste of such potatoes has deteriorated, eating it in significant quantities can lead to poisoning.

What needs to be done so that the potatoes do not turn black during cooking?

Experts say that it is still possible to eat potatoes blackened during cooking. Moreover, this happens not only because of an overabundance of minerals in its composition. Sometimes it all depends on the soil on which it is grown, the variety of potatoes and weather conditions.

In order to understand why the potato turns black after cooking, as well as, it is necessary to inspect it and soak it in water. For people with heart disease, it is important to reduce the starch content, you can even crumble potatoes and change the water several times within two hours. Part of the starch will wash out and remain at the bottom of the container. When cooking, you need to use a bay leaf. If there are no problems with digestion, when boiling, add one tablespoon of table vinegar to one liter of water. You need to cook such potatoes with the lid closed.