How to know if milk is real. How to check the quality of dairy products

Zakharova Ekaterina

Research work on the topic "Determining the quality of milk at home". The purpose of the work: the acquisition of the ability to determine the quality of milk. Task: to learn to distinguish a high-quality product from a low-quality one.

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Department of Education

Vyksa district, Nizhny Novgorod region

Municipal budgetary educational institution

secondary school No. 8

Nomination: research

Determination of milk quality

at home

MBOU secondary school No. 8

Head: Volkova

Elena Vyacheslavovna,

Teacher

primary school

G. Vyksa

2011

1. Setting goals, problems and research methods p. 3

2. Substantiation of the topic p. 4

3.Methods for determining the quality of milk p. eleven

5.Do you know what? with. 22

6. Conclusions p.24

7. Applications p.25

8. Literature review p. 28

Subject :

Determining the quality of milk at home

Target:

Acquiring the ability to determine the quality of milk

Task:

Learn to distinguish a quality product from a poor quality product

Formulation of the problem:

Milk, one of the most importantproducts that a person consumes. It is a raw material for the production of fermented milk products, cheeses, butter.

Do we always consume quality milk?

Is it possible to determine the quality of milk at home?

Problem research methods:

1. Experiment
2. Observation
3. Study
4. Fact matching
5. Analysis of results
6. Results processing
7. Compilation of ratings
8. Literature analysis
9. Statement of conclusions

Milk is an amazing food

prepared by nature.

Academician I.P. Pavlov

TOPIC RATIONALE

Milk, like bread, mankind began to use for food more than five thousand years ago. Milk is the only food product in the first months of human life. It is of exceptional importance in the nutrition of an adult. For old, weakened and sick people, milk is an indispensable food.

It has been established that this product contains over a hundred of the most valuable components. It includes all the substances necessary for the life of the body: proteins, fats, carbohydrates, mineral salts, vitamins. These components of milk are well balanced, making them easily and completely digestible.

Milk is one of the most important human food products. Milk and a great variety of dairy products add variety to the diet, improve the taste, increase the nutritional value of our food and are of great dietary and healing value. “If you drink one liter of milk every day for 1200 months, then you will provide yourself with a hundred years of life!” - so jokingly, said the Swedish scientist Nile Gustavson. These words of the Swedish scientist are confirmed by experimental data, because milk contains all the substances necessary for the body.

Since ancient times, milk has also been used as a remedy for many diseases: in the treatment of the heart, kidneys and other organs.

Dairy products (yogurt, koumiss, kefir, etc.) are an excellent remedy for people suffering from gastrointestinal diseases, tuberculosis; they give a good effect in case of poisoning.

The ancient Egyptians used donkey milk for medicinal purposes. Scientists of Ancient Rome and Greece - recommended milk for the treatment of consumption. Hippocrates attributed various healing properties to different types of milk, for example, goat and mare - the ability to cure consumption, cow - to cure gout and anemia, donkey - many diseases.

In our country, whole cow's milk is most often consumed, and dairy products are prepared from it.

Milk is the most valuable product in the universe, since it contributes to both the physical and spiritual development of a person. Milk effectively treats mental disorders - irritability, fussiness, overstrain, pacifies and relieves insomnia. Our grandmothers knew that the best remedy for insomnia in a child is milk. The child was given a glass of warm milk with honey at night, he slept soundly and became calm. If a person drinks milk at night, then he becomes more reasonable, begins to better understand the world around him, acquires the correct vision of good and evil, the Eastern sages believed. They also recommended drinking it either late in the evening or early in the morning, sweetened with honey orsugar, adding spices: fennel, cardamom, turmeric, cinnamon, saffron and licorice. Moreover, milk, which some attribute the ability to increase body weight, in fact, on the contrary, is able to protect the body from gaining excess weight.

What is the composition of whole milk?

Whole milk contains almost equal amounts of proteins, fats and carbohydrates. The average composition of milk is approximately the following:

Water - 87.2%,

dry matter - 12.8%, including

fats - 3.9%,

squirrels - 3.4 (casein - 2.7, albumin - 0.6, globulin - 0.1),

milk sugar - 4.7%.

vitamins in milk there are about 30. There are especially many vitamins A and B, and in enriched and D. Milk has everything you need to build blood of nervous tissue, muscles and bones. Milk is not a mechanical mixture of different substances. All substances that are contained are either dissolved in it, or like fats and proteins are in solution in the smallest particles. Milk is a homogeneous and fine mixture.

The quality of milk depends on many indicators: feed, processing methods, animal care methods. From a cow of the same breed, depending on climatic conditions, feeding, its content, a different amount of milk is obtained, its quality is also different. The composition of milk varies depending on the time of year, the age of the cow, and its individual characteristics. Feeds have an impact on quality, some of them (rutabaga, turnip, cabbage and fodder, tops, sugar beet and silage) can give milk an unpleasant taste and smell, especially when fed in large quantities.

Nizhny Novgorod milk differs in its composition and quality from many other Russian producers. This is due to the agro-climatic conditions of our region, but the quality program “Buy Nizhny Novgorod!”, which was adopted by the government of the Nizhny Novgorod region in 2007, plays an even greater role.

On January 1, 2009, a new regulation on milk came into force, according to which all dairy products must meet the new quality requirements. Only whole milk will be used for the production of dairy products. Natural dairy products from Nizhny Novgorod producers will be marked with a special quality mark. The product label will indicate that it does not contain artificial colors and milk powder. Goods of high quality are awarded a quality mark in the form of an emblem depicting a green leaf and a blue drop of water marked "Free of artificial ingredients and GMOs."

It is this special sign on the packaging, which symbolizes the purity of nature and everything that grows on the Nizhny Novgorod land, nourishes and feeds its inhabitants.

How to avoid deception?

What you need to know when buying such a necessary product for us as milk?

You need to know some methods for determining its quality. Every buyer can do this. I want to give some recommendations that will help you buy a quality product.

Each buyer should pay attention to the packaging - it is the hallmark of the product, than itcheaper, the less milk will be stored.

I want to do my homework as well.

Methods for determining the quality of milk

How to determine if we are buying quality milk or not?

For the experiment, I took whole homemade milk sample No. 1

and milk of well-known Nizhny Novgorod producers:

Milk "Northern Valley" - sample No. 2

Milk "Merry Milkman" - sample No. 3

Milk "Vyksa" - sample No. 4

And compared them.

Experience 1:

The quality of milk can be determined by appearance

Equipment: glass beaker 250 ml.

Working process:

1. Poured into a glass of milk to the middle of the volume.

2. She carefully examined the milk for the presence of impurities, impurities and noted the uniformity.

3. Let the milk stand for 3-5 minutes and note the presence of sediment. (See Appendix No. 1)

Experience 2:

Determining the consistency of milk

Equipment: chemical test tubes

Working process:

1. Poured milk into a test tube to the middle of the volume.

2. I closed the test tube and shook it slightly to wet the walls.

3. Let the milk drain and evaluate the result within 1-2 minutes. (See Appendix No. 1)

Experience 3:

Determining the smell of milk

Equipment: a test tube with a stopper.

Working process:

1. I poured a little more than half of its volume into a test tube of milk, closed it with a cork.

2. I opened the test tube and immediately sniffed it. The smell is determined by repeated short inhalations. (See Appendix No. 1)

Experience 4:

Quality milk determines its color.

Equipment: chemical test tubes, a white sheet of paper.

Working process:

1. Poured milk into test tubes.

2. She brought a white sheet of paper to the test tube and compared the color. (See Appendix No. 1)

Experience 5:

Determining the taste of milk

Equipment: glass cup, drinking water.

Working process:

1. Poured 10-20 ml of milk into a glass.

2. She took a sip of milk in her mouth, trying to distribute it throughout the mouth, and held it for a while. Defined the taste.

After each sample of milk, rinse your mouth with water and take short breaks between individual determinations. (See Appendix No. 1)

After carrying out all these experiments, I compiled a table and entered the data into it (see Appendix No. 1).

Experience 6:

Determination of the degree of purity of milk

Materials and equipment:

Volumetric test tubes, cotton filters, funnel, glass.

Working process:

1. Placed a cotton filter in the funnel.

2. I lowered the funnel into a glass to collect filtered milk.

3. Pour 50 ml of milk onto the filter.

4. After all the milk has been filtered, carefully remove the filter and lay it on a piece of paper to dry.

5. Compared the contamination of a cotton ball with a standard standard. (See appendix no. 2)

Experience 7:

Determining the presence of impurities in milk

Materials and equipment: test tubes with milk, cotton filters, acetic acid

Working process:

1. Strained milk through cotton filters.

3. Watched what happens to milk. The appearance of bubbles in milk indicates the presence of harmful impurities. (See appendix no. 2)

Experience 8:

Determination of the presence of starch in milk

Materials and equipment: test tubes with milk, iodine solution.

Working process:

1. Pour 5-10 ml of milk into a test tube.

Milk with the addition of starch turns blue, and pure milk turns yellow. Diluted milk has a floury or starchy taste that is very difficult to hide. (See appendix no. 2)

After carrying out all these experiments, I compiled a table and entered the data obtained into it (See Appendix No. 2).

I chose this topic because I love milk very much. It saturates the body with vitamins, gives me strength for a good study. I would like to learn more about the beneficial properties of milk and talk about them so that all children drink milk and be healthy.

Milk should be included in the diet of every student. Just one glass of milk partially compensates for the breakfast missed by the schoolboy.

The beneficial properties of milk are written in the scientific literature. I decided to find out if the students of our class drink milk drinks, do they know about their beneficial qualities? What drinks do our class think are healthy? And which ones are delicious and favorite?

Students of grade 4 "b" of secondary school No. 8 in Vyksa made ratings of healthy and favorite drinks.

So, according to my classmates, the top three healthy drinks included: - milk (Hooray! In the first place!);

Tea;

Cocoa (see Appendix No. 3)

But the following were named as favorite drinks:

The juice;

Tea;

Carbonated water (see Appendix No. 3).

Analyzing the results of the survey, I realized that many students in the class eat drinks that are of little use or even harmful to the child's body. Therefore, together with the class teacher, we decided to hold a class hour in the classroom on the topic “About tasty and healthy food” with the involvement of a pediatrician and the head of the school cafeteria. And also organize an excursion to the Vyksa Dairy Plant.

1. Humans first began to eat animal milk in 8-9 millennium BC, when the peoples who inhabited the Middle East managed to domesticate sheep and goats. In the 7th millennium, in the territory of modern Turkey, people began to graze cows, thus getting one of the most popular modern products into their diet.
2. The second wife of Nero, who was known as a great beauty, always took 500 donkeys with her on a trip in order to be able to take milk baths that improve the skin.
3. Cow's milk is the most consumed type of milk - its annual production exceeds 400 million tons!
4. An ancient sign that milk sours faster during a thunderstorm is still valid now, when the conditions for the production and storage of milk have changed dramatically.
5. The fattest types of milk are the milk of seals (the fat content in it exceeds 50%) and whales (up to 50% fat). The least fatty milk is given by donkeys and mares.
6. From soybeans, so-called soy milk is produced, which is eaten or used in cooking in the same way as cow's milk. It contains useful amino acids, vitamins and minerals, but the calcium content in it is low. In this regard, manufacturers often saturate soy milk with calcium salts.
7. Of all vegetable proteins, almond protein is the closest to the protein of mother's milk, and therefore it is often used for the production of milk formulas for children. The donkey is the domestic animal whose milk composition is closest to human milk.
8. 250 ml of milk contains 300 mg of calcium. That's as much as 7 sardines, 2.5 cups of raw broccoli, 3 cups of peanuts, or 4 cups of black beans.

End of form

Findings :

1. The milk samples studied by us showed that they meet the quality standards that apply to milk.

1. Samples of Nizhny Novgorod producers do not differ much in terms of indicators from whole homemade milk. A small amount of starch is allowed in packaged milk (sample No. 4). It is added to create the consistency of the product.

1. If you do not have the opportunity to drink whole homemade milk, you can use milk from Nizhny Novgorod producers with a quality mark.

1. 25% of the classmates I interviewed consider milk to be a product necessary for the child's body, but, unfortunately, only 10% of the children surveyed consume and love milk drinks daily.

1. I hope that my work will help children learn about the benefits of milk and dairy products. They will definitely include it in their diet. So, they will get sick less and learn better!!!

Application No. 1

Application No. 2

Internet resources:

1. http://www.LifeOkey.ru/view_post.php?id=86

2.http:// www.nachalka.com/nod/284

3. http://psylib.org.ua/books/aurob04/txt14.htm

Milk bought on the market can be checked for water content in nanometers, that is, how much it has been diluted with it, using toilet paper or a paper napkin.

The match is dipped into milk, having previously mixed it, they are taken out and the collected drop at the end is slowly lowered onto paper. It should not be large so that it does not spread, but remains convex. Water is absorbed by the paper, a wet circle appears around the milk drop.

With whole milk, this circle is narrow, but it dries for a long time, up to 2 hours.

10% water is poured into milk, which means it dries faster, in about an hour.

30% water is added, then the wet circle is wide and it will dry in half an hour.

If the milk is adulterated by half, then the paper dries out in 15-20 minutes.

Do we always buy and consume quality milk? Once milk was considered a useful product, natural whole milk contains easily digestible proteins, mineral salts, carbohydrates, fats, vitamins, which are necessary for the normal growth and life of a human body of any age.

I fermented store-bought milk several times to get yogurt, firstly, it simply didn’t turn sour for a couple of days, and secondly, having turned sour, it smelled so bad and tasted very unpleasant, bitter ...

How to check milk at home, does it contain impurities?

1. Pour the purchased milk a little into a glass and drop acetic acid into it. If bubbles appear in the milk, it contains harmful impurities.
2. Pour milk into a glass (a small amount), drop iodine into it. If the milk turns blue, then it contains starch.
3. If you have litmus paper, you can use it to check for impurities in milk. If there are chemical impurities in the milk, the litmus paper will turn red, and if soda is present in the milk, then this red paper will simply turn blue. Litmus paper from the presence of soda in milk can immediately turn pale green.

Health to you and tasty milk!

I have been in the village - there local grandmothers told a rather specific way. Pour some milk into a glass and throw a match. If the match sinks, the milk is not fresh, not of high quality. And if the match remains on top, then this is pure and tasty milk.

I don’t know how true this is (maybe the grandmothers decided to circle the city kid around the nose), so let’s leave it to the conscience of the grandmothers. Another surest option is to drop a little iodine and watch the color change. If it turns white with a yellow tint, then the milk is good.

As you can see, there are ways. Of course, there are a lot of additives in purchased milk. It is better to take fresh. But now where can I find it?

Milk today is very often diluted with water. Especially sellers in the market or grandmothers selling near shops like to do this. You can check the quality of milk at home. To do this, you will have to conduct several tests: mix milk and alcohol in a ratio of 1: 2. Shake this mixture well and quickly pour it onto a saucer. If the milk is not diluted, then after about 5-7 seconds, flakes will appear in it. And if the flakes appear only after a few minutes, then it is clear that you got milk diluted with water. Moreover, the more water in the milk, the longer it will take for the appearance of flakes.

Manufacturers have also learned to mix in milk and other additives that allow milk not to sour for a long time. This, for example, starch, honey, soap, soda, lime, boric or salicylic acid and even gypsum. This, of course, can lead to food poisoning. To determine such chemical impurities, you can use litmus paper: if the milk is not diluted, then the blue litmus paper will turn red and the red one will turn blue; if there is a lot of alkali in milk (this may be an indicator of the presence of soda impurities), then the red litmus paper will turn very blue, and the blue one will not change its color; if any acid is added to the milk, then the blue litmus paper will turn red, and the red one will not change its color.

Knowing about this test, you can easily check the quality of the milk you bought. A little something.

Indeed, it is very important to know how high quality the purchased milk is, whether it contains any substances, whether it is diluted or not.

Let's try to figure out at home what kind of milk we have in front of us (what kind of milk we bought):

• most often sellers dilute milk (diluted with water).

You can find this out in the following way:

• You can find out whether starch has been added to milk or not using iodine:

To check tediously add just a couple of drops of iodine to a glass of milk. The presence of starch is confirmed by a change in the color of milk - it acquires a blue color.

• You can also determine the quality of milk in the following simple way:

It will be necessary to pour milk into the container without closing it completely / cover with a lid and put the container in a warm place:

The easiest and most proven way is to take a little milk and put it in a warm place. if the product is of high quality and natural, it will begin to thicken and a little kefir will turn out from it, which will have a pleasant smell and will resemble jelly.

If it does not change its structure and acquire an unpleasant smell, it is a fake!

I like the cycle of films Habitatquot ;. They always intelligibly tell how to determine the quality of products, milk, sausages and others. About milk, it seemed to me an affordable way to test on pets. A cat will never drink unnatural milk and eat sausages with chemistry. I don’t have a cat, but the dog drinks homemade milk, but not from the store.

Good whole milk should bubble up when poured into a glass.

I think that there is no way to determine this for sure, at least without special chemicals and reagents. I always read the composition and buy milk only from trusted manufacturers. For example, I personally visited one of the milk factories, and now I am not afraid to buy the products of this company.

To all of the above, I can add a way to determine whether milk is diluted with water or not, and how much.

Alcohol will help with this. You need to mix alcohol and milk one to two and shake well for something about a minute, and then immediately pour it into a plate. We observe and wait for the appearance of white flakes in the mixture poured onto a plate. What is important is the time after which these flakes appear. The faster, the higher the quality of the milk. 5 - 7 seconds is an indicator that the milk is not diluted with water.

Milk is a tasty and healthy product.

But this is if the milk is natural, of animal origin and without any impurities.

There are several ways to check the quality of milk:

• add 2 parts of alcohol to 1 part of milk and shake the resulting mixture for 1 minute. Pour the milk-alcohol mixture onto a saucer and note how long it takes for casein flakes to form. If this happens within 5-6 seconds, the milk is of high quality and not diluted with water. If you have to wait longer, the milk is diluted with water.
• if milk is poured in a stream into a glass of warm water, then you can also understand whether it is diluted or not. Diluted milk will immediately mix with water, undiluted milk will gather in a white clot at the top of the glass.
• The presence of starch in milk is determined using iodine. A few drops of iodine are added to a glass of milk, and if the milk becomes bluish, starch is present in it. If the milk has acquired a yellowish-orange color, it is of high quality.

• There is such a simple way: pour a little milk into a test tube or into another container and add nitric acid drop by drop (sold in chemical reagent stores). If the milk becomes more and more saturated yellow with each drop, gradually turning into orange, then your milk was produced from skimmed milk powder.

Are we always confident in the quality of the products we buy? In particular, when it comes to such a drink as milk. At present, the opinion about the benefits of milk for the human body is no longer so unambiguous, because the purchased version may contain a huge amount of impurities and additives harmful to the body, which simply level all those valuable qualities of a natural product for which we love it so much. But there are several proven ways to determine the freshness and quality of a dairy product that are available to us at home.

How to check the freshness of milk at home

Milk is a product unique in its composition, which is useful for a person 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. In goat, unlike cow, there are no caseins that cause allergic reactions. However, it is important for testing that both of these species contain proteins.

It is possible to determine the exact quantitative composition of proteins in milk only in laboratory conditions.

The soda method

1. Pour half a glass of milk.
2. Pour ½ tsp. soda.
3. Let's look at the reaction. If foam appears, the milk is not fresh.

Boil method

1. Pour some milk into a saucepan.
2. We put it on the fire and wait for it to boil.
3. If the liquid has curdled, the milk is spoiled.

Determining freshness by drop

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

1. We put a toothpick into a container with milk.
2. We drip liquid on the nail.
3. 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 if milk is sour is the nose. A sharp sourish smell is a clear sign of a product that is not fresh. You also need to look at the consistency and uniformity of the liquid. Uneven thickening or the appearance of white flake-like inclusions indicates that the milk has deteriorated.

Effective ways to check the naturalness and quality

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

It is interesting. A very unreliable but fun way to test if milk is natural is to give it to a cat. The animal will turn away from the drink with additives. True, there is a great chance of error: firstly, a cat can be unpretentious, and secondly, manufacturers can be very resourceful 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 milk powder. Perhaps the situation is not so clear, but if you decide to buy products in a supermarket or are just choosing a fresh milk supplier, 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 is yellowish, then this is the result of the work of the mammary glands of a cow or goat. But white or white with blue color indicates the presence of impurities. Resourceful manufacturers add lime, chalk, flour, starch to milk to improve the external performance of the product.

Detecting the presence of starch

The surest way to determine if there is starch in milk is to drop iodine into a healthy product.

In the manufacture of products, it is not uncommon to add starch to skimmed milk in order to give thickness in this way. Iodine is required to determine this additive in a drink.

Instruction:

1. Pour some milk into a glass.
2. We drip iodine.
3. Let's look at the reaction. If the liquid has acquired a bluish tint, then there is starch in the milk. If yellowish circles have gone, then you are lucky - there are no additives in such milk.

Determine if 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 suitable only for cow's milk, since the casein contained in it is necessary for the reaction.

Instruction:

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

Instruction:

1. Pour warm water into a glass.
2. We begin to slowly pour in the milk.
3. If the stream immediately mixes with water, then the product is diluted, and if it gathers in a clot at the top of the glass, then it is natural.

Antibiotics and other impurities

Real milk has a dense texture

In order for milk to be stored longer, antibiotics are added to it. It is very easy to check their presence in the purchased product.

Instruction:

1. We leave the drink in a container with a loosely closed lid for a day in a warm place.
2. 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's and cow's milk. To do this, most often soda or salicylic acid is added to it. You can determine the presence of these impurities using litmus paper:

In principle, it is possible to detect the presence of any impurities using acetic acid:

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

Instruction:

1. Pour milk into a glass.
2. Add the acid drop by drop from the test tube.
3. If the product starts to turn yellow and then turns orange, then it is not natural.

But sometimes there is no need to purchase a reagent; it is possible to determine the fact of milk recovery from powder by eye. When shaking in glassware, opaque particles remain on the walls.

How to check the fat content of a product

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

1. We take two glasses, pour milk into one.
2. We pour liquid from one to another.
3. We evaluate the result - fatty milk will not leave streaks and marks on the walls of dishes, but diluted milk will be smeared in a glass. The same reaction will be with milk, to which palm oil has been added.

Excessive consumption of palm oil can cause problems with blood vessels. It is difficult to excrete by the body and contains almost no linoleic acid, which is valued in other oils.

How to check the quality of milk

Milk test - we check the quality of milk at home

1. When buying, pay attention to the expiration date of milk and storage conditions. Buy only dairy products where there is refrigeration equipment. At the expense of the market - decide for yourself whether it is worth the risk. And pay attention, two hours is the maximum period for transporting fresh milk without using a refrigerator.

2. To test milk at home

buy litmus paper. It will show the presence of chemical impurities in the milk. If the milk is not diluted, then the litmus test will remain unchanged. Litmus paper will determine if there is soda in milk (in an alkaline environment, litmus paper will turn blue). Baking soda is added to make milk last longer. How to check the quality of milk

3. Also, in order for the product not to turn sour for as long as possible, salicylic acid can be dissolved in milk. If it is present in milk, then the litmus paper will turn bright red.

4. To thicken milk

dishonest manufacturers can add starch. To check, you can drop iodine into milk. If the milk turned blue, then it could not have done without "innovations"! How to check the quality of milk

5. To increase the volume, milk is diluted with water. Checking with alcohol (vodka). Pour a little milk into a glass, add alcohol (vodka) to the glass twice as much milk by volume. We mix everything. If the milk is of high quality, then flakes will appear, it is casein protein that has curtailed from alcohol. To better see the flakes, you can pour the mixture into a saucer of a plain dark color. In diluted milk, flakes do not form immediately, but after some time. The more water in the milk, the later the flakes will appear.

6. How can you detect chalk in milk.

To do this, you can pour vinegar. If there is abundant foam, then there is chalk in the milk.

7. Long-term milk quality check. Defective milk will not pass this test!

How to check the quality of milk. Take a dry clean glass and pour milk into it. Cover it with a napkin and leave it on the table. Do not stir while observing.

normal milk

should become sour to taste in a day (maybe earlier, it all depends on the temperature in the room).
The next stage in the transformation of milk is curdled milk, the sour taste should be greatly weakened. Curdled milk should be a homogeneous mass, like jelly, which is easily mixed. How to check the quality of milk

What can be seen during the observation and what conclusions can be drawn about the quality of milk:
The milk turned sour in more than a day. This means that there are preservatives in milk.
- Initially, milk has a boiled flavor. This suggests that the milk was boiled, or there is a concentrate in its composition.
- It does not sour at all and after a while an extraneous smell appears in the milk. It indicates that this is not natural milk, it is a surrogate (maybe powdered).
- It turns sour in time, but yogurt is not formed in the form of a single jelly-like mass. So the milk was diluted with water.
- It turns sour in time and forms yogurt of the desired consistency, but a thin sour cream film has not formed on the surface of yogurt. This means that the milk is skimmed, i.e. partially driven through the separator, or diluted with reverse (not water), or the milk is simply not fat.

How to check the quality of milk

Today, you will not surprise anyone with the postscript "natural" on a package of milk, the shelf life of which can reach up to six months, and at the same time it can be stored at room temperature. Is this milk good? Everyone decides for himself. We will tell you what to look for when choosing quality dairy products.

Natural dairy products can be bought even in large cities like Moscow. You just need to know a few not very complicated rules that apply to the choice of dairy products in general.

Firstly, "milk" without stabilizers and preservatives cannot be consistently the same quality. The batch should differ from the batch, as the input raw material - milk - differs. Its composition depends on the time of year, the weather, the quality of grass, hay and the area in which the cow lives.

Second, pay attention to price and composition. Don't go cheap! Natural dairy products cannot be cheap with all the producers' desire. Only non-dairy components such as vegetable fat, milk powder, starch, etc. can reduce the price of the product. But in the composition they are not always indicated.

Thirdly, shelf life. If milk is stored for 3 months, this is not very normal. Such a product is rather useless, as it has been sterilized. Sterilization kills both the bad microorganisms in milk and the good ones. Remember that products without additives have a short shelf life: from 3 to 7 days, depending on the production technology.

Cottage cheese

The main danger when buying cottage cheese is to run into a product in which milk fat was replaced with palm and coconut oil fats (this is very cheap), and the desired taste was achieved with the help of flavorings and additives. What's wrong with this product? The melting point of vegetable fats is higher than the body temperature of a healthy person. This means that fat remains in the body, clings to the stomach, negatively affects blood vessels and general condition. Therefore, eating such cottage cheese is dangerous for health.

Unfortunately, at home it is impossible to distinguish "vegetable" cottage cheese from natural. This is a complex laboratory examination.

But you can remember distinctive features of natural curd and always call them to mind when choosing products.

1. Real cottage cheese should be white.
2. Consistency - soft, spreadable or crumbly, depending on the technology of preparation.
3. The smell is characteristic milky and sour. Cottage cheese made from powdered milk does not have a very pronounced smell, and even more so taste.
4. Proper cottage cheese should not be bitter.
5. But the humidity or dryness of cottage cheese is a variable indicator. From batch to batch, the product may be drier or wetter, depending on how the whey is squeezed out. Whey may even be visible in the curd, but it should not float in it.

Milk

The first thing you need to pay attention to when choosing milk - the way it is processed. At a minimum, milk needs to be pasteurized. It kills dangerous bacteria, but retains beneficial microorganisms in the product.

Raw milk is prohibited in our country. Therefore, it is very dangerous to buy it from an old woman in the market. It is not known what her cow is sick with. If the milk of a sick cow is not boiled, you can catch a dangerous infection - brucellosis, for example.

Naturalness of milk easy to check by how it turns sour. If milk is made from powder or preservatives are added to it, then it becomes immune to lactic acid bacteria. Such milk will not make curdled milk. Pour milk into a glass, dip a spoonful of sour cream into it. Did you get sour milk? If yes, then milk is natural.

If the label says milk not homogenized(that is, the fat in such a product is not brought to a homogeneous mass), which means that after a couple of days, cream should settle on the walls of the bag or bottle. No cream? This means that the fat globules in the milk were nevertheless broken, and the milk was brought to a homogeneous mass.

Shelf life- the main indicator of the naturalness of milk. Pasteurized milk without preservatives should be stored for no more than 5 days.

Butter

A myth is circulating on the Internet that butter, the fat content of which is below 82.5%, is not butter at all, but margarine. And for some reason, many people believe this myth. Actually this is a lie. The naturalness of the oil does not depend on its fat content.. Fatty butter is obtained from heavy cream. Less fat - from less fat cream. That's the whole secret.

One of the main indicators of quality butter is its soft creamy aroma. It should not be sharp or too bright.

Butter cooked in winter is white, and in summer it has a yellowish tint, which indicates that the cow was eating fresh grass.

Another natural factor plastic. High-quality butter is easily and evenly spread on a sandwich, and cooked in violation of the recipe crumbles and crumbles.

Also remember that quality butter can't be cheap. If you see a "ahovo" low price - do not be tempted. Most likely, you are dealing with a cheaper product - a spread or margarine, which really wants to appear like butter.

acidophilus

This is a very useful product, popular in Soviet times. Acidophilus is similar to kefir, but contains a completely different lactic culture - acidophilus bacillus, which survives digestion in the stomach, enters the intestines and takes root well there, working from the inside like an eraser, destroying putrefactive microbes. Acidophilus is the best natural remedy for bowel cancer prevention.

The main factor in the naturalness of acidophilus is shelf life. Acidophilus bacillus lives in the product for no more than 5 days, so if the product is stored longer than this time, do not rely on a therapeutic and prophylactic effect. The consistency of the product should be viscous and viscous, color - white, taste - sour.

Kefir

Classic kefir, made according to all the rules, should have a snow-white color and a uniform consistency. It should not pour into the glass in lumps. If so, the cooking technology is violated.

Real kefir is made from live kefir fungi. They are the most useful thing in kefir. And it is they who change the taste of the product over time. For example, today's kefir can and should differ in taste from three-day kefir.

Natural kefir with live sourdough foams slightly when poured into a glass. It should not taste too sour.

The shelf life of a good kefir should not be more than 7 days. And the rule works with natural kefir: fresh - weakens, three or four days - strengthens. Those who have a sensitive digestive system can check the naturalness of kefir in this way.

When dried sourdough is added to pasteurized milk instead of live kefir fungi, the product changes its status dramatically and can no longer be called kefir.

Article provided by the dairy company "Izbenka"