Ethanol emulsion for testing of fats

Materials :                                                                                               

- Ethanol                                                                                                

- Sticky rice (Lontong)                                                                            

- Brownies                                                                                              

- Rice                                                                                                      

- Coconut oil                                                                                           

- Alcohol                                                                                                 

- Bread

Equipments :
 - Test tube
- Filter funnel
- Mortar & Pestle

- Stiring rod
- Test tube rack
- Filter paper

Preparation of a solid sample :

1. Completely crushes adequate amount of food with a clean and dry mortar and pestle.

2. Transfer an adequate amount of crushed food sample to a clean test tube

3. Adds 2cm ethanol above the food sample

4. Shakes the test tube thoroughly and safely .

5. Allows the solid to settle for about 3 min

6. Decants the ethanol carefully into a clean,dry test tube without transference of food particles.

7. Adds 2cm of de-ionized water to the test tube

8. Compares each result with the negative control

9. Compares the heights of the emulsion layer of all the samples

Process

• Add the food sample to 2 cm3 of ethanol, shake well.
• Allow to settle in a test tube rack for 2 minutes for food to dissolve in ethanol.
• Empty any clear liquid into a test tube containing 2 cm3 of distilled H2O.
• A MILKY-WHITE EMULSION is a positive result: lipid is present.
• If the mixture remains clear, there are no fats present in the sample

Substance tested	Presence of spot	Lipids presence ?
Brownies	Yes	Yes
Rice
Sticky rice
Cooking oil	yes	Yes
White bread	Yes
Whole bread	No	No

By : Via Noviani { year 11}