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Lipid

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Objective: 1. Test for the solubility of the lipids in the several common solvents.

2. Test for the saponification and the property of the soap solution (stearate) 3. Test for the existence of the acrolein.

4. Test for the unsaturation.

5. Test for the unsaturation in the way determination of the iodine number of a fat or oil.

Result: 1. Solubility Test: (0.5) solvent Ether Chloroform Acetone Ethanol Water Triacetin + + + + - Butter + + + - - Peanut oil + + + - - Stearic acid - - - - - Oleic acid + + + + - Glycerol + + + + + (+) means soluble (-) means insoluble (+/-) means slightly soluble 2. Saponification: A. 1ml of soap solution + 1 ml of saturated NaCl solution.

Here we found that there is the white ppt. at the bottom of the tube.

And this kind of ppt. is not soluble in the water, but soluble in the ether.

B. 1 ml of soap solution + 1 ml of CaCl2 solution.

Here we can find there is also the white ppt. at the bottom of the tube.

This kind of ppt. is not soluble both in the water and in the ether.

C. 1 ml of soap solution + 1 ml of diluted HCl solution.

In the test, we found that there are the white ppt. at the bottom of the tube.

This kind of ppt. is also insoluble in the both water and ether.

3. Acrolein Test: Peanut oil Stearic acid Glycerol Heat No smell No smell No smell Heat + KHSO4 No smell Smell Smell 4. Test for Unsaturation: Sample Observation 1 / 2 +++ 3 + 4 ++ 5. Determination of the iodine number of a fat (Hanus method): Vol. of Na2S2O3 react in oil sample = 9.2 (ml) Vol. of Na2S2O3 react in blank control = 21.8 (ml) Conclusion: 2. The soap solution will have reactions with the salt reagents with the sign that appears the white ppt. And these kind of ppt. will not dissolve in the water, and not easy to dissolve in the ether except the sodium salt.

3. The peanut oil is negative to the KHSO4 while the stearic acid and the glycerol are both positive to the reagent.

4. The reagent 1 is the stearic acid, the...