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 sour-milk products. It has long been known that purchased milk is of little use, expired even less. Many people, despite this fact, do not cease to love and cook dishes based on it. There are basic options for assessing the quality of milk and its suitability for consumption.

How to determine the freshness of milk

The composition of cow and goat milk has several differences, but the freshness of this product is subject to the same verification. Cow's milk contains casein, unlike goat’s milk, it 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 as follows: the housewives took an unlit match and threw it into a glass. If she did not drown, the milk is fresh and suitable for consumption. Consider several ways to check the product for freshness.

Method number 1. Soda
Pour half a glass of milk, pour 10 g. soda, watch the reaction. The appearance of foam indicates the staleness of the product.

Method number 2. A drop
Unlike store milk, homemade milk is famous for its high fat content. Checking the indicators is quite simple. Dip a toothpick in a bowl of milk. Put a dairy product on the nail. If the drop did not spread, the liquid can be considered fresh.

Method number 3. Boiling
Pour a small amount of milk into a heat-resistant container. Put on the stove and wait for the first bubbles to appear. If the liquid begins to coagulate, be sure that the dairy product is spoiled. Do not 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 pungent odors and be uniform (without clots).

Checking milk fat

To check milk for fat content, you will need any tests for water content. In case of dilution of the product, fat content is significantly reduced. There is another proven method.

Take two containers, fill one with milk. Pour the liquid from the first bowl into the second. Rate the result. If milk is fat, it will not leave marks on the walls of the vessel. A diluted product, on the contrary, will spread across the entire surface of the container, indicating that it contains water or palm oil.

Milk quality assessment: important aspects

Many people who do not take shopping milk seriously, often speak negatively about the quality of the supplied product. 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 a visual assessment of 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 a participation of chemical impurities.

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

Identification of signs of starch

Most often, starch is added to the production of skim milk, so the product becomes thicker. To determine the presence of this substance, iodine is needed.Pour an incomplete glass of milk, add a few drops of iodine. Observe the reaction: if the liquid is blue, the milk contains starch. Otherwise, the presence of yellowish circles indicates the absence of additives in milk.

Detection of water in milk

Some factories and farmers, because of their weakness for money, make poor-quality products. Thus, they use an annoying trick, that is, they dilute milk with water.

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

Method number 2. Warm water
The technique is developed for milk of any type (goat, cow). Pour a glass of warm water, then slowly add milk. As a result, when two liquids are mixed, high-quality milk will coagulate, and diluted milk will mix with water.

Impurity test

Often, store 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, a thorough check is necessary.

Antibiotic assessment

For long-term storage of dairy products, antibiotics are added. To identify the presence of these drugs is not difficult. 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 like a jelly-like mass). If nothing similar happens with the liquid, this condition indicates the presence of antibiotics in the product. They, in turn, slow down the spread of sour milk bacteria.

Assessment of Acetylsalicylic Acid and Soda

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

1. Litmus paper. First of all, dip the plate in milk, then evaluate the result. Soda is blue and acid is red.
2. Acetic essence. Take a glass of milk and add a few drops of essence. As a result of the chemical process, bubbles may appear. A similar effect indicates the presence of impurities. If nothing happened, you can be sure of the quality of the product.
3. Nitrous acid. Many manufacturers prepare milk from a low-fat powder. The naturalness of the product can be checked with nitrous acid (sold in household stores). Pour milk into the container, add one drop of acid with a pipette. In case of yellowing and darkening, the product is unnatural.
4. 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 on the walls will remain opaque grains of the product.

It is easy to evaluate the quality of milk, if you have sufficient knowledge regarding possible methods. Check store products for impurities, pay attention to grease and freshness. Use effective methods, do not violate the instructions.

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