How to determine whether milk is natural or not. Studying the quality of milk at home

Milk is a unique product in its composition that is beneficial for people at any age.

The freshness of cow's and goat's milk is checked in the same way, despite the fact that the composition of these products is slightly different. Goat milk, unlike cow milk, does not contain caseins, which cause allergic reactions. However, for testing purposes, it is important that both of these species contain proteins.

The exact quantitative composition of proteins in milk can only be determined in laboratory conditions.

Soda method

Pour half a glass of milk.

Add ½ tsp. soda

Let's look at the reaction. If foam appears, the milk is not fresh.

Boiling method

Pour some milk into the pan.

Place on the fire and wait for it to boil.

If the liquid has curdled, the milk is spoiled.

Determining freshness drop by drop

Homemade milk has a high percentage of fat content and thanks to this you can check its freshness in the following way:

Place a toothpick into the container with milk.

We drip the liquid onto the nail.

If the drop has not spread, the product is fresh. And if it spreads, then there is water in such milk, and it is not fresh.

The surest tool for determining that milk has gone sour is the nose. A sharp sour smell is a clear sign of a stale product. You also need to look at the consistency and uniformity of the liquid. Uneven thickening or the appearance of white specks that look like flakes indicates that the milk has gone bad.

Effective ways to check naturalness and quality

To determine the quality and naturalness of milk, you only need one glass of drink

This is interesting. A very unreliable but fun way to test the naturalness of milk is to give it to a cat. The animal will turn away from a drink with additives. True, there is a high chance of error: firstly, a cat can be unpretentious, and secondly, manufacturers can be very creative in additives.

Antagonists of store-bought dairy products unanimously shout that all kefirs, curds and, of course, milk on the shelves are made from powder, that is, from powdered milk. Perhaps the situation is not so clear-cut, but if you decide to buy products in a supermarket or are just choosing a supplier of fresh milk, it would be useful to know about some ways to check the quality of a natural product . The very first way to determine the naturalness of milk is to evaluate its color. If the product has a yellowish tint, then this is the result of the mammary glands of a cow or goat. But white or white with blue color indicates the presence of impurities. Inventive manufacturers add lime, chalk, flour, and starch to milk to improve the external properties of the product.

Detecting the presence of starch

The surest way to determine whether milk contains starch is to drop iodine into the healthy product.

When making products, starch is often added to skim milk to add thickness. To determine this additive in the drink you will need iodine.

Instructions:

Pour some milk into a glass.

We drip iodine.

Let's look at the reaction. If the liquid has acquired a bluish tint, it means there is starch in the milk. If yellowish circles appear, then you are lucky - there are no additives in this milk.

Determining whether there is water in milk

In addition to the method described above for determining the freshness and presence of water in a natural drink, there is another proven option - using alcohol. But this method is only suitable for cow’s milk, since the reaction requires the casein contained in it.

Instructions:

You can also check whether there is foreign liquid in the milk using warm water. This technique can be used for both cow's and goat's milk.

Instructions:

Pour warm water into a glass.

We begin to slowly pour in the milk.

If the stream immediately mixes with water, then the product is diluted, and if it collects in a clump at the top of the glass, then it is natural.

Antibiotics and other impurities

Real milk has a thick consistency

To make milk last longer, antibiotics are added to it. You can check their presence in the purchased product very simply.

Instructions:

Leave the drink in a container with a loosely closed lid for a day in a warm place.

High-quality milk will begin to ferment and begin to resemble jelly. But the drink with additives will remain unchanged. This is because antibiotics slow down the growth of lactic acid bacteria contained in the natural product.

Manufacturers of dairy products are trying in every way to extend the shelf life of goat and cow milk. To do this, soda or salicylic acid is most often added to it. The presence of these impurities can be determined using litmus paper:

In principle, the presence of any impurities can be detected using acetic acid:

Unscrupulous milk suppliers sometimes hide from consumers the fact that it is made from low-fat milk powder. In this case, you can test the drink for naturalness with nitric acid (it is sold in specialized chemical stores).

Instructions:

Pour milk into a glass.

Add acid drop by drop from the test tube.

If the product begins to turn yellow and then turns orange, then it is not natural.

But sometimes there is no need to purchase a reagent; you can determine the fact of milk recovery from powder by eye. When shaken in a glass container, opaque particles remain on the walls.

How to check the fat content of a product

To check fat content, any of the water tests is suitable. After all, if the product is diluted, then its fat content is significantly reduced. But there is one more test:

Take two glasses and pour milk into one.

Pour liquid from one to another.

Let's evaluate the result - full-fat milk will not leave streaks or marks on the walls of the dishes, but diluted milk will smear across the glass. The same reaction will occur with milk to which palm oil has been added.

Three criteria for assessing the quality of milk powder

Powdered milk is in no way inferior in quality to natural milk, provided it has been properly manufactured

We all know that milk can be natural and reconstituted, that is, obtained by diluting dry milk in water. We’ve figured out how to determine the quality of the first type, now it’s time to talk about ways to assess the condition of dry goods. To do this, you need to evaluate the powder according to 3 criteria.

Milk can confidently be classified as one of those products that are vital for our body. This is the primary source of our nutrition. This product is very rich in a variety of useful substances. Its regular use is the key to good health. It will be very good if milk comes to our table directly from Burenka. Today there are many intermediaries who process milk, pasteurize, sterilize, and also add various additives to it. This is not always very good. They add starch, soda, chalk, acetylsalicylic acid, various concentrates, or generally prepare a whole product from dry. As a result, we do not consume a healthy product, but a harmful one. Therefore, it is very important to know how to determine the quality of milk at home.

In special laboratories you can check its quality or any dairy product. In the laboratory, milk is examined for organoleptic indicators - color, taste, consistency, smell and physico-chemical qualities. The latter include fat mass fraction, density, acidity, purity level and temperature. In theory it’s easy, but in real life you can’t run to the laboratory with a carton of milk or sour cream. Traditional methods of verification will come to the rescue here. In the kitchen, without much effort and knowledge, you can check whether it is natural or not.

Traditional methods of testing milk quality

1. If milk is diluted with water. Very often this product is diluted with water. To find out, pour it into a saucer and add twice as much alcohol or vodka. If the product is of high quality, the liquid will almost instantly turn into flakes. When exposed to alcohol, the milk protein casein tends to coagulate. The more water added to the product and the greater its concentration, the longer this protein will coagulate.

3. One of grandma’s ways to determine the quality of milk is to pour it into a container, cover it loosely and place it somewhere warmer. The pure product will begin to sour within a day. Then you will get yogurt and it will look like a homogeneous jelly mass. If there is anything extra in the milk, it will remain unchanged. This means that a product or antibiotic has been added to the product that slows down the growth of lactic acid bacteria.

As is known, increased growth and development of such bacteria begins in warmth. Milk made from milk powder will not sour either. After a certain time it will smell unpleasant.

If it sours, but does not become a uniform consistency, it means it has been diluted with water.

Be sure to have a small layer of cream on top of the curdled milk. If this is not the case, then the milk has been skimmed and passed through a separator. The result does not mean that the milk is not of high quality. There is simply almost no fat in it.

4. Does milk contain soda? Litmus paper also does a good job of checking its quality. Let's take it in two colors - red and blue. Dip each of them one by one into the milk. If the product contains soda, the red piece of paper will turn blue in such an environment. If the red one turns blue, then the milk contains, for example, acetylsalicylic acid.

5. Is there chalk in milk? It is common that chalk is added to it. Vinegar will help us here. When chalk interacts with vinegar, foam will appear.

Which milk is better?

If you buy it in a store, and not from a barrel at the market, then you need the simplest thing - look at the date. Although now they are cheating with this too. It is better to take milk packaged in a tetra pack; it is stored longer, as it is completely protected from ultraviolet radiation. In plastic bottles, vitamins and fats quickly oxidize and proteins are destroyed. Milk in plastic bags must be used within 24 hours, or it will quickly turn sour.

You need to be very careful when purchasing and especially consuming this product. If you drink milk often, be sure to use the tips on how to determine the quality of milk listed above.

RESEARCH WORK ON HEALTHY NUTRITION

“Determination of milk quality at home”

INTRODUCTION

Milk is one of the most important human food products. It contains the most essential substances for human health. Fats and carbohydrates are sources of energy. Proteins contain all the necessary amino acids, including those that are not synthesized by the human body.

The minerals contained in milk contribute to the formation and absorption of vitamins and are part of human tissue. Milk contains all known vitamins.

Excluding milk from the diet can lead to a decrease in essential substances in the body.

Currently, a large number of dairy products have appeared on store shelves.

In Novosibirsk it is not often possible to find natural fresh milk on sale from private producers or peasant farms. Novosibirsk residents mostly use store-bought milk in their diet. This project aims to find out the quality of milk from the store and show how the quality of milk can be examined

Object our research becomesmilk , which our parents, and not rarely you and I, buy in a regular grocery store.

Subject research is the process of determining quality milk.

Objective of the project:

Learn to identify a quality product (milk) at home.

Transferring acquired knowledge, skills and abilities to the public by filming and showing a video about “experimental testing of milk quality at home.”

Show the advantages and disadvantages of a certain product to determine the possibility of its use or unacceptability in the diet.

Tasks project:

Conduct a theoretical analysis of the literature on this issue;
Conduct the necessary experiments to determine a quality product;
Draw conclusions and justifications for the work;
Make a video on conducting an experimental test of milk at home;
Screening of the video at the school scientific and practical conference (scientific and practical conference);
Posting the video on the Internet and social networks.

Methods project:

Studying information on the topic;

Experiment;

Observation;

Comparison of facts;

Analysis of results;

Processing of results;

Formulation of conclusions;

Video shooting;

Processing and editing of video files;

Broadcast video.

Project product: determination of the quality of store-bought milk, video about methods for experimental research of milk quality.

Practical significance project is that I conducted experiments to determine quality milk and made a video for parents and students with recommendations for determining the quality of milk at home to determine the possibility of its use or unacceptability in the diet.

THEORITICAL BACKGROUND OF THE PROJECT

Determining the quality of products by smell, taste and color cannot provide complete and reliable information, and sometimes can be hazardous to health. You can check the quality of milk at home, without resorting to the “testing” method. To do this, you do not need to conduct complex laboratory tests; it is enough to have what is always at hand.In addition to diluting milk with water, starch, gypsum, chalk, soap, soda, potash, borax, lime and even chemical products such as boric and salicylic acids are often mixed into it. Some of these substances are mixed in to give the skim milk a whole, undiluted appearance; others - to protect against rapid souring, in general spoilage, to which milk is subjected the more quickly, the more foreign organic impurities it contains.
In fact, mixing the mentioned impurities is not able to protect milk from souring. Moreover, even the most “innocent” of these impurities, for example, bicarbonate of soda, are in fact very harmful and precisely because, as discovered by direct experiments, the admixture, by the way, of bicarbonate of soda serves as the best condition for the increased reproduction of various pathogenic microbes in milk - cholera bacilli, tuberculosis and others. ("Encyclopedia of Technologies and Methods" Patlakh V.V. 1993-2007)

There are several methods for determining the quality of milk. Some of them require special laboratory conditions with the necessary equipment and reagents. But some can be done at home. Milk should be checked immediately after opening the package.

Compound

The first thing you need to check when buying milk is the composition of the product. Currently, in Russia there is a law according to which if milk powder is added to milk, then it must be written on the label that it is a milk drink and, accordingly, this must also be noted in the composition.

When buying a package labeled “milk,” we expect that we are paying for milk, and not for a milk drink that is made from dry mixes. However, sometimes we are deceived with impunity.

The situation with milk in our country is, to put it mildly, confusing. Despite the existence of GOST, technical regulations and other documents, a method has not yet been developed that would allow determining whether drinking milk contains powder.

Abroad, if milk is reconstituted from dry milk, it is written on the packaging - “reconstituted milk,” explainsLarisa Abdullaeva, executive secretary of the Russian Dairy Union.- We came up with the term “milk drink”, but no one indicates this on the packaging

(http://www.aif.ru/gazeta/number/379)

If the milk you bought says in the COMPOSITION section that it is:whole milk , means the milk is of high quality.

If it is written: reconstituted or normalized, it means that the milk is made from milk powder or with the addition of it.

The amount of protein in milk decreases in winter and cannot exceed 3%. And packages often indicate much larger numbers. There is no live milk with such indicators in Russia: animal selection has not been carried out for a long time, and there are complaints about the quality of feed. If natural milk really contains high protein, the manufacturer will use such valuable raw materials for cheese or cottage cheese, rather than making UHT milk from it. (from interviewElena Petrova, OPP expert).

If the packaging indicates high protein content, the milk has most likely been reconstituted.

Determination of impurities

It is quite easy to determine the “purity” of the product; to do this, you need to strain a certain amount of milk through a thick white cloth or cotton pad.

If you notice lint or any grains of substance, it means that sanitary standards were not observed during the production of milk, and such milk can be dangerous.

"Dirty glass"

During this test, we check the thickness of the milk (fat content), therefore, after stirring the milk in a glass, look carefully at its walls; the “dirtier” your glass turns out to be, the better the quality of the milk. It should be noted that the layer of milk on the walls should be uniform.

Litmus.

Sometimes manufacturers whose product sits on store shelves for a long time add soda to the milk, which slows down the souring process. You can determine the soda content in milk using litmus papers.

Most likely, Not every home has an acid-base paper indicator, but if you set yourself the goal of testing food at home before consumption, it is not difficult to purchase it at the pharmacy.

Using litmus papers, you can check the acidity of products, in our case milk.

We pour milk samples into different containers;

It is necessary to moisten one strip of indicator paper in the milk sample;

We wait 1-2 minutes and carefully examine the strip;

We draw conclusions based on the color of litmus paper:

In case of complex adulteration of milk, you should most of all beware of chemical impurities, for the detection of which this test can be of great help. Unskimmed, whole milk has a very characteristic double reaction, expressed in that it is at the same time somewhat alkaline and slightly sour; As a result, blue litmus paper moistened with whole milk turns slightly red, and red litmus paper turns slightly blue.
On the contrary, if there is an excess of alkali in milk, for example, from the admixture of soda to it, then the red litmus paper turns very blue, while the blue one completely retains its color.
In the same way, if an acid is mixed into milk, for example, boric or salicylic, then blue litmus paper moistened with such milk turns bright red; red does not change its color at all.

IODINE

The presence of starch, which is added to milk to give it thickness, can be easily and quickly determined using ordinary iodine from a home medicine cabinet.

A few drops of an alcohol solution of iodine should be added to a small amount of milk.

Blue coloring will indicate the presence of starch in the product;

A yellow-orange color will indicate the absence of starch in the milk.

Alcohol

Using alcohol, you can accurately determine whether milk has been diluted with water. To do this you need:

- to one part milk, add two parts alcohol;

- Shake the resulting mixture vigorously for 1 minute;

- Having finished shaking, it is necessary to pour the mixture of milk and alcohol into a plate or saucer, carefully observing the state of the mixture and recording the time after which white flakes appear in it;

- rapid, within 5-6 seconds, formation of casein flakes released from the whey will indicate the high quality of the milk;

- If the flakes appear late, it means the milk has been diluted with water.

By the time of formation of casein flakes, one can judge the degree of dilution of milk with water. If it took about a minute for the flakes to form, then 20% of the volume is replaced with water, an interval of 25-30 minutes will indicate that the milk contains 40% water, and if casein flakes have only begun to appearafter 40 minutes, this milk is diluted with water by half.

7. Warm water.

By pouring a small amount of milk into a glass of warm water in a thin stream, you can determine with a high degree of probability whether it was diluted with water.

High-quality milk in the form of a white clot will collect at the top of the glass, while diluted milk will behave differently - it will almost completely dissolve in the water, turning it dirty white.

If you pour in milk quickly, high-quality milk will first sink to the bottom of the glass and then slowly dissolve when diluted with water, immediately coloring the water off-white.

8. Filter paper

Another way to determine the degree of dilution of milk with water . If you don’t have filter paper at home, you can use a paper napkin or toilet paper; the main requirement is that they must be of sufficiently high quality.

Dip a thin stick, toothpick or match into the milk and place a small drop of milk on the surface of the filter paper. It is very important that it be as small as possible and at the same time be as convex as possible, resembling a hemisphere in shape. To ensure the reliability of the result, it is better to put several such drops.

Since the filter paper has a finely porous surface structure, it will begin to absorb the water contained in the milk. Therefore, a wet ring will appear on the surface of the paper around the drop; the width of the ring will be greater, the greater the amount of water in the milk.

A drop of undiluted milk will create a wet ring around itself no more than 1 mm thick, which will dry in about 2 hours at room temperature.

A water stain around a drop of milk diluted with 10% water will be noticeably wider and will dry faster - in about an hour. In half an hour, a ring around a drop of milk diluted by 30% will dry, and it will take only 10-15 minutes for a ring left by a drop of milk diluted in half to dry.

Antibiotic check

The milk we buy in the store undergoes special processing. It is purified from various impurities. In order to destroy microorganisms, milk is pasteurized, ultra-pasteurized and sterilized.

Pasteurization - heating milk from 63 degrees to a temperature close to the boiling point. Pasteurization destroys vegetative forms of microbes, and sterilization destroys spores at the same time. When boiling, all microflora of milk is destroyed, with the exception of spores that are resistant to boiling temperatures.

Sterilization milk aims to destroy all microorganisms. In this case, the milk is first heated to 75 degrees, then in a split second it is heated under high pressure. In another method, milk is sprayed and, at the moment of spraying, heated to the temperature of superheated steam. The bacteria die instantly. The milk is then cooled and packaged.

Sterilized milk obtained in one way or another does not change its taste. In a hermetically sealed container, sterilized milk can be stored for a long time at room temperature.

Ultra pasteurization used to destroy microflora and at the same time preserve the natural properties of milk. Ultra-pasteurization is carried out at temperatures from 105 to 150 degrees with exposure from several seconds to fractions of a second. Then the milk is quickly cooled in 4-6 seconds.

Unfortunately, at home it is impossible to check whether the purchased product is natural or made from milk powder. But checking milk for the presence of antibiotics and various substances that slow down the growth of bacteria is very simple. Natural milk without additives, left at room temperature, should turn sour within a day.Pasteurized milk sours within 2-3 days, while ultra-pasteurized and sterilized milk may not sour for quite a long time.

PRACTICAL PART

The practical part includes a description of the work on researching the quality of milk, within the framework of the above studies.

City dwellers' love for natural products - milk and its derivatives - increases in proportion to the distance from the countryside. The skills that help determine the quality of such products are lost.

Entrepreneurial and not very decent traders often take advantage of the gullibility and inexperience of city residents by selling low-grade dairy products under the guise of proven and benign products. Often, stories about the milk yield of cows from their farmstead turn out to be fiction, and the liquid in various containers, called milk, has nothing in common with this product, except for color.

It would seem that the easiest thing is not to buy what is offered outside the store, whose shelves are lined with proven products. But sometimes you want to try real, undiluted, live and perfumed milk so much that all reasonable arguments are brushed aside, the money is given to the seller, and a container with something white inside passes into your hands. True, lately news about the quality of store products has instilled more and more uncertainty in the souls of customers.

Organoleptic testing - taste, smell and color

Once and for all, you should remember that you can only try unboiled milk from a cow that has been vaccinated in a timely manner, is not treated with antibiotics for any disease, is kept in normal conditions and is grazed far from the sides of highways. In addition, the cleanliness of surfaces that come into contact with milk - the udder, the milkmaid's hands, the milk pan, shipping containers and many others - must be impeccable. If you do not know under what conditions the milk was obtained, you should only drink it boiled.

The taste of milk that has begun to sour can be muted by adding sugar, but it will curdle when heated. Milk reconstituted from powder will lack many of the beneficial properties characteristic of a fresh product. The fat content of milk can be easily determined by pouring it from glass to glass: skim milk leaves virtually no marks on the glass walls.

Note: The gastrointestinal tract often reacts with dyspeptic symptoms to homemade milk. Therefore, there is nothing wrong with drinking skim milk, that is, less fatty milk, you just need to be warned about it

You can identify a counterfeit visually. A snow-white tint should alert you, since the naturalness of milk is determined by its yellowish tint. The most popular bleaching additives are starch, chalk and flour. If the white has a blue tint, you have milk, at best skimmed or passed through a separator, or alternatively diluted with water.

Chemical experiments with milk in the kitchen

Pour a small part of the purchased liquid into a separate cup and remember your school chemistry course. Additives that increase the shelf life of milk are baking soda and salicylic acid. Litmus paper will help determine their presence: soda gives an alkaline reaction, acid - acidic, coloring the indicator blue and red, respectively. The presence of starch is checked with a drop of iodine. Good milk will turn yellow, starch will give a dirty blue-gray color.

Chalk and soda will make themselves felt by foaming when vinegar is added to milk. Ethyl alcohol or vodka can help check the fat content of milk. By adding one part milk to two parts vodka (alcohol), after 5-7 seconds you will observe the formation of flakes. This is what coagulated milk protein, casein, looks like. The fewer flakes, the longer they appear, the greater the likelihood of milk being diluted with water.

If the milk passed all the tests, soured on time (a little more than a day at room temperature) and you and everyone at home simply liked it, it makes sense to think about establishing contacts with the seller of such a good-quality product. Cooperation is beneficial to both parties: there are regular customers - there is minimal hassle with sales.

In the photo: children's embroidered bodysuit (Online store Tovarik.com.ua, section For children)

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How to check the quality of milk at home

When buying products in a store, we cannot always be sure of their quality. Especially when it comes to dairy and fermented milk products. It has long been known that store-bought milk is of little benefit, and expired milk is even less beneficial. Many people, despite this fact, do not stop loving and preparing dishes based on it. There are basic options for assessing the quality of milk and its suitability for consumption.

The composition of cow's and goat's milk has several differences, but the freshness of this product is subject to the same check. Cow's milk contains casein, which, unlike goat's milk, can cause an allergic reaction. For this reason, not all people are susceptible to this type of product. Two types are known to contain pure protein.

In the old days, the freshness of milk was checked in the following way: housewives took an unlit match and threw it into a glass. If she hasn't drowned, the milk is fresh and ready to drink. Let's look at several ways to check product freshness.

Pour half a glass of milk, add 10 grams. soda, watch the reaction. The appearance of foam indicates that the product is not fresh.

Unlike store-bought milk, homemade milk is famous for its high fat content. Checking the indicators is quite simple. Dip a toothpick into a container of milk. Place a drop of milk product on your nail. If the drop does not spread, the liquid can be considered fresh.

Method No. 3. Boiling

Pour a small amount of milk into a heat-resistant container. Place on the stove and wait until the first bubbles appear. If the liquid begins to curdle, you can be sure that the dairy product is spoiled. Don’t forget about your own sense of smell, because this is a simple and sure way to determine the freshness of milk. It should not contain any strong odors and be uniform (without clots).

To test milk for fat content, you will need any water content tests. If the product is diluted, the fat content is reduced significantly. There is another proven method.

Take two containers and fill one with milk. Pour the liquid from the first bowl into the second. Evaluate the result. If the milk is fatty, it will not leave marks on the walls of the vessel. A diluted product, on the contrary, will be smeared over the entire surface of the container, indicating the content of water or palm oil in the composition.

Many people who do not take store-bought milk seriously often speak negatively about the quality of the product supplied. They believe that cottage cheese, kefir, fermented baked milk and, of course, milk are prepared exclusively from powder.

An effective way to assess the quality of milk is to visually assess the shade. If the composition is yellow, you have good goat or cow milk. In this case, a snow-white or white with a blue tint indicates the participation of chemical impurities.

Unscrupulous manufacturing companies supply their products with starch (potato, corn), lime, flour or chalk. The listed components improve the aesthetic performance of the finished composition.

Most often, when producing skim milk, starch is added, so the product becomes thicker. To determine the presence of this substance you will need iodine. Pour a partial glass of milk, add a few drops of iodine. Observe the reaction: if the liquid is predominantly blue, the milk contains starch. Otherwise, the presence of yellowish circles indicates the absence of additives in the milk.

Some factories and farmers, due to a weakness for money, make low-quality products. Thus, they use an annoying trick, that is, they dilute the milk with water.

This test option is only suitable for cow's milk because it contains casein. Mix medical (ethyl) alcohol and milk in a 2:1 ratio. You can replace alcohol with high-quality vodka. Shake the prepared mixture for one minute, then pour the contents onto a flat plate. If the milk is of high quality, flakes will form on the surface of the saucer within the first seven seconds. If there are few flakes and much more time is spent on their formation, this means that the milk contains a lot of water.

Method No. 2. Warm water

The technique is developed for any type of milk (goat, cow). Pour a glass of warm water, then slowly add milk. As a result, when mixing two liquids, high-quality milk will curdle, and diluted milk will mix with water.

Often store-bought products are not of high quality. Unscrupulous manufacturers stuff milk with flavor enhancers and other impurities that can increase the shelf life of the composition. To exclude the harmful effects of milk on the human body, it is necessary to conduct a thorough check.

For long-term storage of dairy products, antibiotics are added. It is not difficult to detect the presence of these drugs. It is enough to leave the liquid in a container with an open lid at a temperature of 25 degrees. If the milk is of high quality, the fermentation process will begin (the composition will become similar to a jelly-like mass). If nothing like this happens to the liquid, this condition indicates the presence of antibiotics in the product. They, in turn, slow down the spread of lactic acid bacteria.

Assessment of acetylsalicylic acid and soda content

The pursuit of extending shelf life leads to manufacturers stuffing milk with acetylsalicylic acid and soda. It is not difficult to determine the presence of such substances; let’s consider the main methods.

Litmus paper. First of all, dip the plate in milk, then evaluate the result. The soda content is characterized by a blue color, and the presence of acid is red.
Vinegar essence. Take a glass of milk and add a few drops of essence. Bubbles may appear as a result of the chemical process. This effect indicates the presence of impurities. If nothing happens, you can be confident in the quality of the product.
Nitrous acid. Many manufacturers prepare milk from low-fat powder. The naturalness of the product can be checked using nitrous acid (sold in household stores). Pour the milk into a container and use a pipette to add the acid one drop at a time. In case of yellowing and darkening, the product is unnatural.
Visual inspection. It is not always necessary to resort to chemical experiments. Sometimes it is enough to shake the milk and determine its naturalness by eye. In a glass container, opaque grains of product will remain on the walls.

It is not difficult to assess the quality of milk if you have sufficient knowledge regarding possible methods. Check store-bought products for impurities, pay attention to fat content and freshness. Use effective methods, do not violate the instructions.

How to check the quality of milk

Organoleptic testing - taste, smell and color

The gastrointestinal tract often reacts with dyspeptic symptoms to homemade milk. Therefore, there is nothing wrong with drinking skim milk, that is, less fatty milk, you just need to be warned about it

Chemical experiments with milk in the kitchen