Milk: how to check the quality of milk? Video
The citizens’ love for natural products – milk and its derivatives – increases in proportion to the distance from the countryside. The skills to help determine the quality of such products are being lost.
How to check the quality of milk
The gullibility and inexperience of city dwellers are often used by enterprising and not very decent traders, selling low-grade dairy products under the guise of proven and benign. Often, stories about the milk yield of a cow from her backyard 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 way is not to buy what is offered outside the store, the counters of which are lined with proven products. But sometimes you want to try real, undiluted, live and spirit milk, that all reasonable arguments are swept aside, the money is given to the seller, and a container with something white inside goes into your hands. True, lately, and news about the quality of store products instill more and more uncertainty in the souls of buyers.
Organoleptic test – for taste, smell and color
Once and for all, you should remember that you can taste unboiled milk only from the cow that was vaccinated in a timely manner, is not treated with antibiotics for any disease, is kept in normal conditions and grazed far from the roadsides. In addition, the surfaces that come into contact with milk – the udder, milkmaid’s hands, milker, shipping container and many others – must be impeccable. If you do not know the conditions under which the milk was obtained, you should only drink it boiled.
The taste of milk that has begun to turn sour can be muted by the addition of sugar, but it curdles when heated. Milk reconstituted from powder will be deprived of many of the beneficial properties characteristic of a fresh product. The fat content of milk can be easily determined by pouring it from glass into glass: skimmed milk leaves practically no traces on the glass walls.
The gastrointestinal tract often reacts with dyspeptic symptoms to homemade milk. Therefore, there is nothing wrong with using skimmed milk, that is, less fatty milk, you just need to be warned about this.
Determine the falsification visually. The snow-white shade should alert, since the naturalness of milk is determined by its yellowish tint. Among the bleaching additives, the most popular are starch, chalk and flour. If the white casts blue, then you have milk in front of you, at best skimmed or passed through a separator, as an option – diluted with water.
Chemical experiments with milk in the kitchen
Pour a small part of the purchased liquid into a separate cup and remember the school chemistry course. Additives that increase the shelf life of milk are baking soda and salicylic acid. Litmus paper will help to determine their presence: soda gives an alkaline reaction, acid – acidic, staining the indicator in 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 bluish-gray scale.
Chalk and baking soda will foam when added to the milk vinegar. Ethyl alcohol or vodka will help you 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 curdled milk protein looks like – casein. The smaller the flakes, the longer they appear, the more likely the milk will be diluted with water.
If the milk passed all the tests, turned sour on time (a little more than a day at room temperature) and you and everyone at home just 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 – minimal hassle with implementation.
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