When to collect watermelons from the garden - expert advice. How to choose a watermelon without nitrates at a retail outlet? How to understand that watermelon is good

Watermelons are sweet berries that symbolize warmth, sun and the approach of generous autumn. We are used to eating them in August-September, and we are suspicious of those copies that appear on sale at an earlier date. First of all, linking their off-season maturation with the use of growth accelerators - nitrates. It is known that nitrates in watermelons are able to accumulate in large volumes from nitrogen fertilizers used in the cultivation of melons.

What are nitrates and saltpeter?

Nitrates - they are also salts of nitric acid - are always present in plants: this is an indispensable element of metabolism and the synthesis of protein molecules. Plants take nitrates from the soil to build their cells. Absorbed by the cell, the salts are converted into nitrites, then along the chain - into ammonia, which is necessary for the formation of chlorophyll. That is, in every plant there are salts of nitric acid to one degree or another.

Many believe that saltpeter is what watermelons are pumped with to ripen them as soon as possible. But this is just a trivial name for a water-soluble fertilizer based on nitric acid salts. The main field of application of saltpeter is agriculture.

Additional undesirable doses of nitrates can be formed by excessive application of them in the form of fertilizers to the soil where watermelon grows.

With the purchase of seasonal berries, we are in danger of acquiring low-quality agricultural products: for a profitable ultra-early harvest, some producers overfeed vegetables and fruits with nitrates. Watermelon, without measure "ate" fertilizer, becomes dangerous for the body and causes poisoning.

The SES has established a daily intake of nitrates that is harmless to the body: for an adult, a dose of 50 mg per 10 kg of human weight is acceptable - ~ 0.5 g of nitrates can be taken without health consequences. According to WHO, the allowable dose of nitrates is 3.7 mg, and nitrites - 0.2 mg per 1 kg. More than half of the daily requirement of these substances enters our body with fresh vegetables and canned food.

The allowable rate of nitrates in watermelon is 60 mg/kg. Heat treatment, vitamin C and storage destroy these substances. Since watermelon is eaten a lot and without heat treatment, the danger of getting nitric acid salts in excess of the dose is especially great.

Consequences of excess nitrogen salts

Nitrates, as such, are not very toxic, but they turn into much more dangerous nitrites.- this occurs both in the gastrointestinal tract and in the fruits themselves. In this form, they poison the body, preventing cells from being enriched with oxygen, which leads to oxygen starvation. The process of food poisoning with an increased dose of nitrates occurs in 4 to 6 hours. With severe intoxication, symptoms may appear within 60 minutes.

Symptoms of nitrate poisoning

With excessive ingestion of nitrates into the body, unpleasant and dangerous signs appear that indicate poisoning with nitric acid salts:

• blue lips, mucous membranes, nails, face in general;
• increased salivation, nausea, vomiting and diarrhea;
• pain in the liver and stomach;
• general weakness, chills, shortness of breath;
• severe headache, drowsiness;
• violation of coordination of movement, loss of consciousness is possible.

If characteristic symptoms appear, it is necessary to urgently take an adsorbent drug and immediately seek help from a medical institution.

How to identify a dangerous watermelon

It is important to determine in time that nitrates in watermelon exceed all reasonable standards in order to protect yourself and loved ones from depressing consequences. To do this, the most accurate would be to use instrumental methods:

1. analysis in the laboratory;
2. testing with indicator strips;
3. the use of a special device - a nitrate meter.

Right choice

The listed methods of verification are not available to everyone, so you must rely on the knowledge and observance of some simple rules for buying a watermelon.

• It all starts with the place of purchase: it must be a certified outlet, and not a car on the side of the road or a vegetable collapse on the ground.
• The fruits should lie neatly on pallets and be covered from sunlight.
• A careful inspection of the fruits for their maturity is required. According to GOST, a ripe watermelon has:

1. moderately shiny hard surface;
2. weak ribbing at the stem;
3. dry stalk and withered tendril;
4. when struck with a bent finger, it makes a booming sound.

• Checking the integrity of the cover of the berry: no cracks, damage, rotten and soft areas on the bark.
• The spot from the place where the watermelon touches the ground has a size of no more than a palm - 5 x 10 cm and is even yellow or orange.
• You should not ask the seller to cut out a piece to see what's inside - you can bring microbes that will lead to damage to the fetus and poisoning.

Checking the berry for the presence of saltpeter

There are several easy homemade methods for testing watermelons for saltpeter. The simplest and most affordable is with the help of water. It is necessary to pour ordinary water into a large basin or bath and place the fruit: a watermelon without nitrates will not sink, but will float. Otherwise - if he drowned - there is a high probability of the presence of saltpeter in the berry. You can also cut off a piece, take 20 grams of pulp, mash it and put it in a glass of water. After 10 minutes, the healthy pulp will give the water a light shade or cloud it a little. When coloring a liquid in a saturated color, you can be sure of the excess presence of nitrogen salts in the watermelon and the insecurity of its use.

After checking the whole fruit with water, you can more carefully examine it inside. The following signs will tell the presence of saltpeter in a watermelon:

1. The bark is glossy and too shiny;
2. The flesh on the cut is smooth, without granularity, excessively bright red;
3. Instead of barely noticeable white veins, the pulp has coarse yellow veins;
4. Unripe seeds are almost white.

And finally, some useful tips:

• Before use, do not be too lazy to thoroughly wash the surface of the watermelon, even with detergent - soap. Then rinse with boiled water.
• Nitrates accumulate in the outer integument of fruits and vegetables - even those in which there is no excess of them. Therefore, you should not save and eat away the pulp to the crust.
• After the fruit is opened, it is eaten as quickly as possible. And if, then in the refrigerator and no more than 2-3 hours.
• Watermelon is a delicacy that is good to eat for dessert. It is also recommended to consume it separately from other meals, at intervals of 2 hours before or after the main meal.

Knowing the dangers of a watermelon that has received excess nutrition in the form of nitrogen fertilizers, and following the simple rules for choosing, buying and eating ripe berries, you can protect yourself from the undesirable consequences of poisoning with this delicacy.

Determining the ripeness of a watermelon in the garden - tips, proper care

Watermelon is most often consumed fresh, but it is also pickled, fermented in tubs, candied fruits are prepared from the peels, and the so-called “watermelon honey” is prepared from the juice. The juice and pulp of watermelon perfectly quench thirst, and the seeds of the ripe fruit and the oil made from them are used for medicinal purposes.

Harvesting is carried out as the watermelons ripen. It is believed that it is easier to determine the ripeness of a watermelon in the garden than in a store. It is easy for a non-specialist to make a mistake, however, as a rule, the signs indicating that a watermelon is ripe are quite accurate.

Quick article navigation

Ripe watermelon selection

You can determine the degree of ripeness of a watermelon using the following tips:

• You should not pick or buy watermelons too early. As a rule, they do not reach a mature condition before mid-August;
• The ripe fruit stops its growth, and the “wax” coating disappears from its surface;
• The side that lies on the ground of a ripe watermelon should be yellowish, but not white or green;
• If the watermelon is not very thick-skinned, you can bring it to your ear and gently squeeze it with your hands. If it is ripe, then crackling will be heard;
• A ripe watermelon is lighter than a green one and does not sink in water;
• The peel of a ripe fruit is even, smooth, without cracks, with a characteristic luster. If you draw a fingernail or a sharp object along its surface, the top layer (zest) should be easily removed;
• You should pay attention to the place where the tail grows from. In a ripe watermelon, this area is usually convex and with callused, brightened edges;
• When tapped on a ripe watermelon, a characteristic clear, sonorous sound will be heard.

A dry tail is often considered a sign of the maturity of a watermelon. However, you should not rely only on him: the tail could dry out after the fruit was plucked.

Growing watermelons

It is not so difficult to grow a sweet watermelon in the garden if you know the biological characteristics of this crop, its requirements for light, heat and mineral nutrition:

• In the southern regions, it is possible to grow varieties from different ripeness groups, in the forest-steppe and woodland - only early and medium-early ones;
• Watermelon prefers uniform heat without sudden changes (20-30 degrees), a sufficient amount of warm moisture in the soil and at the same time dry air;
• Watermelon seeds intended for sowing are stored at 18-22 degrees Celsius. In addition, only two to three year old seeds should be used, otherwise there will be few "female" flowers on the plant;
• Immediately before sowing, the seeds need to be warmed up in the sun for a week. Soil temperature at the time of sowing should be at least 12-14 degrees at a depth of 10 cm;
• Sow watermelon under the hoe to a depth of 5-6 cm, put 3-5 seeds in each hole. Then cover with fresh soil and lightly press down;
• It is necessary to leave the aisles large - 120-200 cm, and the distance between the holes in one row should be 70 cm;
• As weeds appear, the beds need to be weeded. After the appearance of true leaves, it is necessary to leave only one, the most developed leaf;
• The fruits of early ripening combs ripen 30-35 days after setting, mid-ripening - after 40-45, and late-ripening - after 50 days.

http://podskazchik.com

The ability of gourds to gratefully accept nitrogen supplements and store nitrates in reserve is known. But for a person, such a berry can be dangerous. You need to know how to choose a watermelon without nitrates. These harmful substances are present in any vegetables in small quantities. Watermelons are champions in the accumulation of nitric acid salts.

Why are nitrates dangerous to humans?

In the human body, nitrates are converted to nitrites in the large intestine and absorbed into the blood. In this case, nitrites form the compound methemoglobin. Hemoglobin in the blood is needed to deliver oxygen to cells. Methemoglobin does not perform this function and oxygen starvation begins in the body. At 30% substitution, nitrate poisoning occurs, at 50% death may occur.

Slight poisoning is expressed by depression, nausea, vomiting, diarrhea. The doctor diagnoses poisoning by an enlarged and dense liver. The danger is higher in children, as they have a small body weight, and there is no enzyme capable of converting methemoglobin to hemoglobin. Therefore, a baby cannot be given watermelon to a baby.

In the human gastrointestinal tract, protein products are broken down, amines and other nitrogenous compounds are present. Combining with salts of nitric acid, carcinogens, nitrosamines are obtained.

WHO has defined as an acceptable daily dose of nitrates 3.7 mg, nitrites 0.2 mg per kilogram of human weight. In terms of a weight of 70 kg, this will be 350 mg of sodium nitrate.

During heat treatment, in the presence of vitamin C, during storage, nitrates are destroyed. The danger of nitrates in watermelon is great precisely because it is eaten without pre-treatment and in large quantities.

How to determine nitrates in watermelon?

If earlier the advice was not the most correct in the off-season, then modernity is making adjustments. There are new ultra-early varieties and hybrids that ripen early, without accelerators. Such watermelons are small, only 1.5-2 kg, and we were taught not to choose small fruits. So, if the variety is ultra-early, then the watermelon cannot be large.

Therefore, the study of sweet berries should be carried out in the aggregate for a number of reasons:

• appearance;
• the structure of the pulp in a home study;
• use of methods and control devices.

Watermelon research starts at the counter. You can not buy goods from the collapse of the roadside. For a day of standing in a gassed environment, the product will pick up a lot of exhaust gases, no less harmful than nitrates. On the ground, the crust will become dirty, the grains of sand will injure the shell, and it will not be possible to completely wash such a watermelon. Usually, roadside trade is illegal, the goods do not have a sanitary certificate on the content of harmful substances.

It is safe to buy agricultural products, including watermelons and melons, in special places and with a quality certificate.

Watermelon should have a dry tail. It should be carefully examined, a sign that the watermelon was removed green will be a soaked tip or cut off with a sharp knife. In addition, this will be a sign that the watermelon has been stale for a long time. And without a tail, you should not take the fruit. This means the seller has something to hide. The tail can dry naturally in the garden of an unripe watermelon, which is specially turned over several times, twisting the tail.

Stripes of dark and light colors should be contrasting, not blurry, the pattern is clear. In a ripe watermelon, you can slightly scratch the skin, and then a dense white layer and a clearly audible watermelon smell will be found below. All this is a sign that the watermelon has recently sat in the garden.

On examination, you need to check well if there is a puncture in the peel of the watermelon, through which they served what the watermelon is pumped with for quick redness. And not only watermelon, other melons and tomatoes also receive injections from unscrupulous sellers. Saltpeter injection accelerates redness.

You can not buy a watermelon with black dots on the surface, a small rotted spot, with a crack or dent. You can not ask to cut a triangle to inspect the middle. A cut fruit with an unwashed peel, a dirty knife can lead to bad consequences.

To find signs of nitrate watermelon at home, research needs to be continued. First, lower it into a bowl of water. If the fruit is ripe, it will float. A drowned watermelon can not be checked, returned to the owner. After that, wash the watermelon with soap and a brush, drain.

The cut fruit should have a grainy surface, not a smooth, glossy cut. Seeds should be developed and black. On the cut there should not be thick yellow bundles, nitrogen supply overpasses. The veins are thin white, this is the normal structure of the fruit. The flesh should not be in the middle of an intense color, but gradually turn yellow towards the periphery. These are signs of the presence of a large amount of nitrogen. A watermelon with nitrates, the photo of which is posted below, shows its inside view.

Finally, put a piece of watermelon 20 grams into a transparent glass and knead in water. If the water becomes cloudy, everything is fine. If stained, this indicates the presence of nitrates. Moreover, the more intense the color, the more impurities in the watermelon.

The instrumental research method is the most reliable. He suggests:

• laboratory analysis;
• research using indicator strips;
• using a special device, a nitrate meter, or an ecotester.

Only a specialist will decide to keep a tripod for sample titration and potassium alum at home. But this is how the amount of nitrates in agricultural products is checked in the laboratory. There are test strips that are inexpensive, they are not determined very accurately, approximately. And you can buy an ecotester device that gives a result and a warning about the dangerous content of nitrates.

If a dangerous dose is found, watermelon should not be eaten, it is better to part with it. In order for the risk to be minimal, you should wait until mid-August and only then feast on watermelon. But even at this time, vigilance should be observed. Producers try to get a big harvest and they always feed, only during a certain growing period.

How to choose a sweet watermelon?

When buying a watermelon, experts advise choosing "girls". From a scientific point of view, this is not applicable to berries. It does not happen among the fruits of boys and girls. However, folk signs show that a watermelon with a flat or slightly deepened top is sweeter and has fewer seeds. "Boys" are considered if there is a small tubercle at the top. Perhaps these are some features in pollination, but this selection rule works.

Another sign of a ripe berry may be a small orange spot, this place the fruit lay on the ground. If the filling went quickly, the earth was warm, the spot was small, the berries were tasty. If the spot is large, white, then the taste of watermelon will be different. This means that the berry lay on the ground for a long time, the ground was cold, so you should not expect sweetness from such a berry.

When cutting a watermelon, you need to leave 3 cm of pulp near the crust, fertilizers accumulate there. And give the children a piece from the very middle. No need to eat a lot of goodies in one sitting. It is better to stretch the pleasure, eat the fruit in small portions, while listening to the state of the body.

Bon appetit and good health!

How to choose a ripe watermelon without nitrates - video

There is about a week left before the official start of the season for the sale of watermelons, however, unauthorized trade in melons on the streets of Moscow has been going on since mid-July. Consumers are outraged not only by the high price, but also by the quality of the fruit: watermelons that are artificially ripened with the help of nitrates pose a health hazard.

At the same time, sellers of watermelon breakups in most cases cannot present either a trade permit or quality certificates.

Permission to trade melons will be valid from 1 August . The Moscow Department of Consumer Market and Services explained that it is not recommended to buy watermelons before this date - it is better to wait until the end of summer, when they will definitely ripen.

The number of gourd breaks in the capital this summer will be almost two times less compared to last year - total 450 . In addition, retail outlets will operate under the new rules. Sellers are required to work in special clothing, carry a medical book and documents confirming the quality of the products.

Where to choose watermelons

In Moscow, the sale of melons "from the ground" is prohibited. Sales outlets should be equipped with mesh chests and special scales instead of household, medical and postal scales. Sellers should not cut and sell watermelons and melons in parts, in slices.

In addition, visual information about the operating hours of the outlet and the legal address of the trade organization should be placed on the tray or collapse.

To be on the safe side, it's best not to buy watermelons from "spontaneous" markets where products are not checked by sanitary services, and always ask if they have documents. And even more so, you should not buy at the breakups near the roads: there the products absorb toxins.

Some producers stimulate the ripening of gourds with nitrogen fertilizers, which leads to the accumulation of nitrates in watermelons. The consequences of their use can be severe - acute infectious poisoning or chronic intoxication, which doctors call "cumulative effect".

How to identify a nitrate "bomb"

It is impossible to determine a nitrate watermelon by eye if it is not cut. A berry should not even be tasted if its flesh is riddled with yellow or light yellow fibers or has a purple hue.

If you soak the pulp of a nitrate watermelon in water, it will turn red or pink due to the high content of nitrates. A "healthy" watermelon will make the water slightly cloudy.

If you knock on a nitrate watermelon, it feels like you are hitting a half-mast ball. In appearance, such a watermelon may be ripe, but if it does not crack when compressed, it means that it has not ripened without someone else's "help"

What should a watermelon look like without flaws

There is a widespread belief that a large watermelon is "nitrate". This is not true: for example, for the “chill” variety, 10-20 kilograms is far from the limit.

The ideal watermelon should be large enough without being too heavy and with a distinct striped pattern. In order to determine the natural ripeness of a watermelon, first of all, you need to pay attention to the stalk - the tail at the top of the fruit must be dry.

The purchased watermelon should not have cuts and cracks - through which microbes enter, causing intestinal infections.

There is a myth that a ripe watermelon should ring if you pat it with your palm. In fact, the sound depends on whether the pulp inside has softened or not. Just the green fruit will ring, and the ripe watermelon should be deaf.

The crackle that a watermelon makes when you squeeze it with your hands is a good sign. You can safely buy such a product.

The earth spot on the lower side should preferably be yellow, not white.

And the last. A ripe watermelon can be easily scratched - by running your fingernail over it, you can easily remove the top layer of the peel.

When choosing a melon, connoisseurs advise paying attention to the aroma that its peel should exude, the softness that is felt to the touch, and the absence of light brown spots.

What to do in case of "nitrate" poisoning

In addition to nitrates, watermelons can contain microbes and even heavy metals. In case of poisoning, it is necessary to drink as much water as possible to prevent dehydration and reduce the symptoms of the disease.

Is watermelon useful?

There is conflicting information about the benefits of watermelons. Some say that the fiber of watermelons contains potassium, which is washed out of the body when taking diuretic drugs. Therefore, watermelons are advised to be consumed in diseases such as cystitis and nephritis.

At the same time, there is an opinion that all gourds, although they contain fiber, are poorly absorbed, loading the stomach. That is why doctors advise children and the elderly over 50 to give up juicy fruits.

The material was prepared by the online editors www.rian.ru based on information from RIA Novosti and open sources

An amazing berry, which can be difficult to break away from, has a pleasant sweet taste, perfectly quenches thirst and contains a great variety of useful vitamins and elements - ideal for summer. However, difficulties may arise at the time of buying a watermelon, because every year there are more and more unscrupulous sellers who put up for sale not only tasteless fruits, but often simply dangerous due to the high content of nitrates. Therefore, in order not to overshadow your summer meal and please yourself with the most appetizing pulp, you should know some of the subtleties of choosing a ripe watermelon.

Choosing a high-quality, ripe watermelon is important not only because of the taste, but also because of the nutrients in its composition. The more natural the product, the more benefits it will bring to your body.

The composition of the berry contains vitamins of groups B, A, C, E, as well as iron, potassium, calcium, magnesium, phosphorus. Watermelon has such beneficial properties as cleansing the liver, kidneys, improving metabolism, lowering cholesterol and overall strengthening of the body.

Note! A high content of nitrates can harm the body and negate all the beneficial properties of the berry, so it is very important to choose good-quality products.

Everyone wants to eat only natural, first-class and healthy products. But unfortunately, some sellers go to various tricks to sell low-quality goods and get more profit. To prevent this situation from happening with the purchase of a striped berry, you should know some signs of a ripe watermelon and recommendations for choosing a fruit.

Video: how to choose a ripe, tasty and sweet watermelon

These tips will help you choose the right sweet, ripe and healthy watermelon:

Council number 1. Pay attention to the appearance of the fetus. It should not have any cracks, dents, scratches or any other damage. Otherwise, damage can become a convenient "entrance" for germs and bacteria. The berry should have contrasting, bright stripes. The crust should shine and not be matte. As a rule, ripe watermelons have a hard rind that is not easy to pierce with a fingernail.

Tip #2. Pay attention to the date. With natural cultivation without chemistry, the fruits ripen in the second half of August and until the end of September. Try not to buy fruits at an earlier date, because unscrupulous producers stuff the plant with growth stimulants and chemical fertilizers for early ripening.

Tip #3. Focus on size. You should not opt ​​for a fruit that is too large (perhaps it is “stuffed” with chemicals) and berries that are too small (there is a big risk of choosing immature product).

Council number 4. A ripe watermelon should have a yellow or orange spot.. This means that the fruit ripened in the fields in a natural way and was in contact with the ground, absorbing the warm rays of the sun. In a normal fetus, the spot size should be about five to ten centimeters. But do not choose a product with a white spot, it indicates that the berry was not allowed to ripen on the melon!

Tip #5. There is an opinion that watermelons can be "girls" and "boys". It is believed that girls are the most delicious fruits and they have fewer seeds. Male berries are slightly larger in size, and their lower part is convex, there is a small speck. In female specimens, the lower part is most often flat, flattened, the spot is larger.

Tip #6. When choosing a watermelon, it is highly not recommended to cut off a piece of pulp from the fruit to determine ripeness. Indeed, by the time you transport the fetus home and start treating, microbes can multiply in it.

Tip #7. Buy berries in the right places. More detailed information on this subject is waiting for you below.

Tip #8. If you want to choose a safe, tasty, ripe watermelon without nitrates, you you should check with the seller whether he has a certificate for the products. If the seller does not have such a certificate, then you should doubt the quality of the products and look for another point of sale for the juicy berry. Also, early sales of watermelons may indicate a high content of harmful substances.

Tip #9. Carefully examine the stalk (that is, the tail) of the fetus. A high-quality, ripe watermelon should have a yellow, dry tail. The presence of a sluggish, greenish stalk indicates the immaturity of the fetus. A very dry tail may indicate that the product is overripe or spoiled. Some sellers want to cheat and cut off the tail in order to sell low-quality goods.

Tip #10. Identify a ripe watermelonsound will help. When tapped or clicked ripe watermelon make calls th sound j. Although there are experts who claim that ripe berries should be just a dull sound . And some believe that the sound, in general, is not able to help test the watermelon for ripeness, since watering affects the deafness or sonority of the sound - if the fruits were well watered before harvesting, they will be sonorous, if not watered, then deaf.

Video: how to choose a ripe watermelon: signs of sweetness

How to test watermelon for nitrates at home

Unfortunately, it is difficult to choose a ripe watermelon without nitrates, because it is almost impossible to independently check the fruit for their content when buying, unless, of course, you have a special nitrate-determining device - a nitrate meter. But you can conduct a small experiment at home and understand whether the product is worth eating or not.

There are several signs that indicate the high content of nitrates in watermelon:

1. There are white or yellow streaks in the berry, as well as seals in the pulp.
2. When the fruit is immersed in water, it sinks to the bottom and does not float (a quality product should float).
3. Place a small amount of pulp in water for 15 minutes. If the liquid turns bright pink or red, then the berry has a high content of nitrates. And if the water becomes a little cloudy or pale pink, then the berry is of high quality.

Advice! The highest concentration of nitrates in the berry is near the crust, so you should not bite into the watermelon in these places.

Where is the best place to buy watermelons?

It is important not only to be able to choose the right ripe watermelon, but also to buy a valuable food product in the right places, the quality of the product largely depends on this. When choosing a place where you plan to buy a treat, you should pay attention to the following recommendations:

• It is highly not recommended to choose watermelon at points of sale near highways, as gourds absorb heavy metals and other harmful substances found in exhaust gases.
• Berries should be stored in clean trays and neatly arranged.
• Avoid points of sale where watermelons are laid out on the floor and may come into contact with dust and dirt.
• The seller must have a complete set of documents required for sales, have a medical book.
• It is not recommended to buy a food product in spontaneous markets, it is better to give preference to special stores, fairs.

You can determine the ripeness of a watermelon in the market or in a store without any problems, knowing only small recommendations and exact signs of ripeness. The main thing is not to rush to buy, because it is better to wait and buy a tasty and healthy product in the season than to buy much earlier than the usual ripening period and eat a harmful delicacy stuffed with chemistry. Happy shopping and delicious watermelons!

Video: how to choose a watermelon and check for nitrates with your own hands at home

In contact with