Step-by-Step Method:

1. Prepare the Sample:

• Use a clean, grease-free test tube.
• Add 2 cm³ of the sample to be tested into the test tube.

2. Add Ethanol:

• Add 5 cm³ of ethanol to the sample.
• Shake the test tube thoroughly to ensure all the lipid in the sample is dissolved in the ethanol.

3. Add Water:

• Add 5 cm³ of water to the test tube and shake gently.

4. Observe the Results:

• A cloudy-white emulsion indicates the presence of lipids in the sample.

5. Control Test:

• As a control, repeat the procedure using water instead of the sample. In this case, the solution should remain clear.

This test is useful for detecting lipids in a variety of food and biological samples.