Here are some simple tests that you can perform at home to check the quality of the milk you buy.
- Kickstart with the starch test
Starch, a carbohydrate, is commonly found in potatoes. If added to milk, it reduces its fat content by boosting its carbohydrate content. Just add 2 tablespoons of salt to about 5 ml of the milk you want to test. If the mixture turns blue, then you can be certain that starch has been used for adulteration.
- Water, water everywhere. Not a drop of milk?
Water in the milk you buy is not going to harm your health as such, unless the water itself is impure. However, its presence means that your milkman or vendor is engaging in a practice that amounts to cheating. In order to check for this, just put a drop of the milk on your fist or a slanted surface and let it slide down. If the milk leaves behind a trail, it has been mixed with water.
- Your children might be consuming chemicals
Synthetic milk is usually made by mixing chemicals with soap, and adding them to natural milk. Usually the bad taste gives it away, but if you do not want to risk a taste, then the best ways to ascertain that the milk is synthetic are:
- Rubbing – synthetic milk feels soapy when rubbed
- Heating – synthetic milk turns yellowish in colour when heated
- Reduce it to the last drop
Take about 80 ml milk, and boil it slowly for over 2 to 3 hours, until it solidifies and hardens slightly. If the residue is rock solid, and rough, that means the milk has been adulterated. However, if the residue is oily, then you can rest easy about its quality.
- Drinking Urea?
Urea is added to milk by unscrupulous vendors and manufacturers to boost its shelf life. However, it doesn’t affect the taste of the milk and, as such, is harder to detect, unlike other adulterants. To detect its presence, mix half tbsp of milk with soybean or arhar powder and shake well. After 5 minutes, place a litmus paper in this solution for 30 seconds. If the litmus paper changes colour from red to blue, your milk has urea.
Chemical tests
Here are some more tests you can perform to check the quality of your milk. However, since these employ certain chemicals, it is advised that you take the help of someone who knows how to handle them with precaution.
- Checking for Vanaspati/Dalda
Vanaspati is not good for health, especially if consumed in large quantities. To check for vanaspati adulteration, add 2 tbsp of Hydrochloric Acid and 1 tbsp of sugar to 1 tbsp of milk. The mixture will turn red if it the milk is impure.
- Checking for Formalin
Formalin is a transparent preservative and can be used to store milk for long periods of time. As a result, there is a high chance of formalin being used in packaged milk. The test for formalin’s presence however, requires certain precaution. Take 10 ml of milk in a test tube and carefully, add 2-3 drops of Sulphuric Acid to it. If the milk is adulterated with formalin, then a blue ring will appear at the top of the mixture.
