Why do some lipids and proteins give positive results to molisch test?

Add to 2 cc. of egg-white solution 3 drops of a solution of a-naphthol in chloroform; shake and pour cautiously down the side of the test-tube concentrated sulphuric acid so that two layers are formed. If no color is produced, put the tube aside and examine in a few minutes.

If the Molisch test is positive, a carbohydrate is present in the protein molecule