Saturated & Unsaturated Fats level in cooking oil- Urgent Help!

[Nida]

Hey Everyone!

 

I work for a company that does brand activation. One of our brands is a cooking Sunflower oil.

 

I read about the Iodine Test conducted to see the different levels of unsaturated and saturated fat in cooking oils.

 

Below is the test that i followed

 

 

Materials

The materials required for the science fair project:

- 1 bottle of peanut oil
- 1 bottle of canola oil
- 1 bottle of corn oil
- 1 bottle of soya bean oil
- 1 bottle of olive oil
- 5 test tubes
- 1 test tube stand
- 1 eyedropper
- 1 bottle of iodine
- 1 stopwatch
- 1 measuring cylinder

Procedure

1. For this science fair project, the independent variable is the type of oil used for testing - peanut oil, canola oil, corn oil, soya bean oil and olive oil. The dependent variable is the time taken for the iodine color to clear when the iodine test is performed, and will be measured with a stopwatch. The constants (control variables) are the amount of oil used for testing, the number of drops of iodine used and the temperature of the environment, which remained at room temperature.

2. Clean the 5 test tubes were and arrange them in the test tube rack. Label them according to the oils used for testing - peanut oil, canola oil, corn oil, soya bean oil and olive oil.

3. Measure 20ml of each type of oil with the measuring cylinder, and pour into the respective test tubes.

4. Drip 3 drops of iodine into the first test tube. Start the stopwatch immediately and record the time taken for the purple color of the iodine to disappear, as shown below.

5. Repeat Step 4 on the 4 types of oil, and record the results in a table.

 

 

The Problem is that once the idodine disappers for a few seconds and comes back again! I dont know why is this happening. Also i tried this with 2% tincture iodine.

Can someone please help me with this, as i need to do this test in front of my seniors, i have to be sure of what i am doing.

 

Thanks in advance!