We buy harmless vegetables: how to check potatoes for nitrates at home and what is it for

Vegetables and fruits are the basis of a healthy diet. It is a source of vitamins, minerals, nutrients necessary for the body, a means of preventing cancer, pathologies of the cardiovascular and digestive systems. However, when buying, you need to pay attention not only to appearance, but also to quality. If a product looks appetizing and attractive, this does not mean that there are no harmful substances in it.

It turned out that even the most popular root vegetable - potatoes - is unsafe and may contain nitrates. In the article we will tell you how to check potatoes for nitrates at home, how these substances are dangerous for the body, and how to choose high-quality potatoes.

Why is the content of nitrates in potatoes dangerous?

What are nitrates and where do they come from? Nitrates are salts and esters of nitric acid, components of mineral fertilizers... Plants usually take nitrogen from the soil, it is needed to form chlorophyll, a vital component for plants.

If you fertilize the soil with nitrogen-containing substances, the yield of potatoes will increase dramatically, but root crops will accumulate it in excess of the norm. The concentration of nitrates is influenced by climatic, seasonal and weather conditions, soil properties and composition, methods of protecting plants from diseases and pests, harvesting and storage conditions.

For reference. The accumulation of nitrates is facilitated by a sharp change in temperature, cool rainy weather, wet swampy soil, acidic or over-calcified chernozem, and untimely fertilization.

Excess nitrates are toxic to humans: in the body, nitrates are converted to nitrites and nitrosamines. Nitrites are converted into nitric oxide and contribute to the expansion of blood vessels, but nitrosamines are highly toxic compounds. They affect the liver, cause hemorrhages, hypoxia, muscle contraction, sometimes accompanied by short-term loss of consciousness. Most have pronounced carcinogenic properties - it increases the likelihood of malignant tumors.

Exceeding the permissible levels of nitrates can cause food poisoning, the manifestations of which will be nausea, vomiting, abdominal pain, diarrhea. Simultaneously with intoxication, the body temperature rises to 39 ° C, muscle and headache is felt. Loss of fluid through vomiting and stool leads to dehydration.

Take a note:

Medium late potato variety Wizard

Unpretentious potato variety "Crimean Rose"

Early table potato "Tiras"

Permissible content in the composition

Science has identified norms for the content of nitrates in potatoes and products from it - 250 mg / kg... However, these standards are not a guarantee in terms of health safety. It all depends on how much nitrate-rich food you eat. The norm of 500 mg of nitrates per day is considered acceptable, and already 600 mg is toxic.

How to identify potatoes with nitrates

Even when choosing fresh and attractive-looking potato root crops, one cannot be sure that they will be useful, and there will not be a nitrate product on the table. Therefore, it is advisable to use the potatoes that were grown on their own without the use of "chemicals" or in guaranteed safe conditions.

If you buy root vegetables at a market or store, it is important to evaluate their quality, paying attention to the organoleptic properties and storage conditions.

For reference. The benefits of young potatoes are exaggerated, in addition, they can be dangerous. The vegetable is not fully ripe and continues to grow, the nitrogen metabolism inside the tubers is high, therefore the nitrate content is too high. During storage, the level of nitrates decreases, they pass into nitrogenous compounds that are safe for the human body.

In appearance

When buying potatoes, pay attention to the appearance of the root vegetables. If there are green areas in the tubers, then the concentration of toxic solanine in them is much higher. When cleaning, such areas should be removed, and the potatoes should be subjected to a longer heat treatment.

Council. Choose medium sized root vegetables. Large ones can be oversaturated with nitrates, small ones did not have time to grow and mature.

It is not recommended to buy root vegetables with black spots - most likely, tubers are sick with late blight. Often the potato infects the wireworm, it bites into the tuber, making passages, into which fungi and bacteria are then introduced, provoking rot. Potatoes with round holes on the tubers must not be eaten.

Pay attention to storage conditions... The fruits should lie in special trays with a height of at least 20 cm, be protected from the sun, since a poisonous substance - solanine - forms in them under direct rays.

Read also:

Mid-early table potato "Romano"

Unique in appearance and excellent in taste Picasso potato variety

Using a nitrate meter

A nitrate meter will help control the quality of vegetables and fruits, including potatoes. it the device detects the presence and concentration of hazardous substances in products.

The principle of operation is simple. The device is programmed with an extended list of products and norms for the content of nitrates, just select the desired product.

Check the vegetable by piercing the tuber with a probelocated at the bottom of the device. If, as a result of the measurement, the screen turns green - the content of nitrates is normal, yellow - a slight excess of the norm, red - nitrate substances are in excess, the product is dangerous, unsuitable for consumption.

Reference. Manufacturers allow an error of 15%, which is associated with the uneven distribution of nitrates in the fruit.

Using test strips

Test strips are designed for the determination of nitrates in tubers potatoes at home. The fruits are cut lengthwise into two equal parts, a strip is inserted between the halves and tightly clamped. After 10-15 seconds, remove the strip and compare the resulting shade with the color palette on the instructions.

Red-purple color indicates a high concentration of harmful substances - such potatoes cannot be used.

Traditional methods of checking the content of nitrates in potatoes

Traditional methods are less informative and reliable, but to some extent help you check potatoes for harmful compounds:

1. The nitrate roots look unnaturally even.
2. To determine the presence of nitric acid salts, you need potato juice and a solution of diphenylamine in sulfuric acid. Freshly squeezed vegetable juice is poured into a test tube and a few drops of diphenylamine solution are dripped. If the product accumulates harmful substances in excess, the reagent turns blue.
3. After cutting the potatoes, pay attention to the flesh. The nitrate pulp will ooze water and the dampness of the tubers. Environmentally friendly potatoes are resilient: if you cut them, you hear a crackle and juice.

Tips and tricks for choosing

Vegetable growers share valuable tips and tricks on how to choose organic potatoes and reduce the content of harmful substances, pesticides and nitrates:

1. You should not buy new potatoes earlier than May-June. The biological ripening period of a vegetable in nature is August-September.If you buy early varieties, there is a high chance of getting a product generously stuffed with nitrates.
2. Removing the skin to a depth of more than 1 cm and prolonged heat treatment reduce the content of nitrate substances and make the fruit edible.
3. It is possible to lower the concentration of nitrates if, before cooking, peeled root vegetables are soaked in cold water for half an hour and changed twice. However, such actions wash out starch, other substances useful for the human body, together with nitrates.
4. Do not buy damaged or cut potato tubers.
5. Green potato tubers are unsuitable for consumption because they contain solanine. For plants, it serves as protection against damage by bacteria, some types of insects, and can be toxic to the human body. Poisoning is possible after eating unpeeled and thermally unprocessed potatoes.
6. Ask the seller for a certificate of the State Sanitary and Epidemiological Supervision or other documents certifying the quality of the vegetable.
7. If it is easy to damage the peel with a fingernail, it means that such potatoes were grown on nitrogen and mineral fertilizers.
8. If potato tubers have dried out, shriveled and become soft during long-term storage, refuse to use such a product, since the concentration of solanine in it exceeds the permissible norms and is toxic to the human body.

Conclusion

Buying tasty and healthy potatoes is not as easy as it seems. The fruits may contain not only vitamins and minerals valuable for the body, but also toxic compounds. There are practically no side effects from taking acceptable doses of nitrates. When consumed in large portions, they can cause food poisoning, hypoxia, liver dysfunction, and provoke hemorrhages and convulsions.

There are different ways to determine the concentration of nitrates in potatoes. The simplest and most reliable are nitrate meter or test strips, alternatively organoleptic properties and external signs. Methods for detecting harmful compounds will protect you from purchasing a substandard and dangerous product.