Lipids: Sudan IV test.
Lipids include a variety of molecules that dissolve in non-polar solvents such as ether, acetone, methanol, or ethanol, but not as well in polar solvents such as water. Triglycerides (fats) are abundant lipids made of glycerol and three fatty acids. Tests for lipids are based on a lipid’s ability to selectively absorb pigments in fat-soluble dyes such as Sudan IV Several solutions and their test results for the Sudan test are presented in the table below:
- Is salad oil soluble in water?
- Compare tubes 1 and 2. What would you expect the distribution of the dye to be with respect to the separated water and oil?