All of us must have been told about the benefits of drinking milk everyday by our mothers and grandmothers. And the fact is that milk is definitely good for your bones and teeth as it is a rich source of calcium. However, with increased chances of adulteration and contamination, the purity of milk is at stake and so is your health and more importantly, that of your children and the elders in the family, as these people can be particularly sensitive towards any chemical additives in the milk. In order to combat this problem, you can use some simple methods to check the purity of milk at home and do away with a supplier who gives you impure milk.
Here are some simple tips to check the purity of milk at home:
Test #1: Milk Slip Test
Pouring drop of milk on smooth, vertical surface results in its stopping or flowing very slowly, leaving behind a white trail, which is an indication that the milk is pure. On the other hand, if the milk contains water or any other substance, it will flow down rapidly, without leaving a trail.
Test #2: Reduction by Boiling
Some milk is boiled on medium flame, stirring continuously for a few minutes till it starts turning into a semi-solid substance (Khoya). The reduced milk is allowed to cool for an hour or two. If the khoya turns out to be oily, the milk is deemed to be pure, otherwise it has some water mixed in it.
Test #3: Ice Cream Test
A delicious way to check the purity of milk is to freeze it into ice cream. All you have to do is mix in the milk some sugar, condensed milk powder, ice cream powder and cream, and set it in trays inside the freezer till it solidifies. Good quality milk ensures creamy and delicious tasting ice cream while watery milk will yield a poor quality ice cream.
Test #4: Test Tube Test
A chemical called paraphenylene diamine, which is easily available at any pharmacy, can be used to check out whether milk has been adulterated with hydrogen peroxide or not. It can be done with a simple chemical test, by adding a few drops of paraphenylene diamine to a liter of milk and shaking it well. If the color of the milk changes to blue, it can be concluded that the milk contains hydrogen peroxide, otherwise the milk is pure.
Test #4: Lemon Juice Test
This is another simple and reliable test to confirm the purity of milk. Heat a liter of milk on medium flame and squeeze in juice of half a lemon in it as the milk starts boiling. Keep stirring. If the milk curdles right away to form soft aromatic cheese, it is pure while impure milk results in formation of rubbery substance.
Using these simple examinations, you can make sure that the milk you are using at your home is pure and there is no compromise being made with the health of your family. A device called lactometer can also be used to test the purity of milk.