Milk is an essential part of our daily diet, but unfortunately, it can sometimes contain impurities such as urea, formaldehyde, starch, and water. It is crucial to test the purity of milk before consuming it, whether it’s packed by reputable brands or bought from milk vendors. Regularly conducting these tests will help ensure that the milk you purchase is free from undesirable chemicals.
To assess the suitability of milk for consumption, you can perform the following simple tests in the comfort of your home:
1. Milk Slip Test: Place a drop of milk on a vertically polished surface. Pure milk will stop or flow slowly, leaving a white trail. If the milk quickly flows down without leaving a trace, it may be diluted with water or other substances.
2. Purity Test: Boil milk over low heat for 2-3 hours, or until it becomes thick like khoya (solidified milk). Oily residue after boiling indicates high-quality milk, while rock-solid or rough residue may indicate adulteration.
3. Starch in Milk: Mix two tablespoons of salt (iodine) with 5 ml of milk. If the milk is impure, the mixture will turn blue, indicating the presence of added starch. No change in color indicates purity.
4. Checking for Synthetic Milk: Synthetic milk is produced by mixing chemicals, such as soap, with natural milk. You can identify synthetic milk by its taste—it may feel soapy when rubbed between your fingers. Additionally, when heated, synthetic milk tends to turn yellow.
5. Vanaspati in Milk: Milk’s natural creamy consistency is free from added water. However, some vendors may add Vanaspati or vegetable ghee to achieve a similar texture. To check for this adulteration, combine one spoon of milk and one spoon of sugar with a few drops of HCL (hydrochloric acid). If the mixture turns red, it’s a sign of possible adulteration.
6. Urea in Milk: Mix half a tablespoon of milk with Soyabean powder and shake well. Dip a litmus paper into the mixture. If the litmus test strip changes color from red to blue after a short period of time, it indicates the presence of urea in the milk.
When consuming milk, it’s essential to be cautious, as these adulterants can have harmful effects on our health. Milk is a crucial component of our diet, and by following these home tests, you can ensure that the milk you consume is pure and safe.