Home Based Tests
1. Detection of Water in Milk
Procedure:
- Place a small drop of milk on a smooth, clean surface (e.g., a polished floor or plate).
- Tilt the surface slightly to observe the behavior of the drop.
Observation:
- Pure milk: The drop will flow slowly, leaving a white trail behind due to fat and protein content.
- Adulterated with water: The milk will flow quickly without leaving a trail.
2. Detection of Detergent in Milk
Procedure:
- Shake 5-10 mL of milk in a test tube or bottle vigorously for 5-10 seconds.
- Let it settle for a few seconds.
Observation:
- Pure milk: Little or no froth will form.
- Adulterated with detergent: Excessive froth will form and remain stable.
3. Detection of Starch in Milk
Procedure:
- Take 2-3 mL of milk in a small container.
- Add 2-3 drops of iodine solution (available in first aid kits).
- Mix gently.
Observation:
- Pure milk: No color change.
- Adulterated with starch: A blue-black color will appear.
4. Detection of Urea in Milk
Procedure:
- Take 5 mL of milk in a small container.
- Add 1 teaspoon of soybean or arhar (pigeon pea) powder and mix well.
- Let it sit for 5-10 minutes.
Observation:
- Pure milk: No change in smell.
- Adulterated with urea: A pungent ammonia-like smell will develop.