Furfural reagent: A 1 per cent solution (w/v) of furfural in ethanol

 

Place 1-2 mg of suspect material (preferably powdered) in a test tube and shake with 1 ml of petroleum ether. Transfer the extract to an evaporating dish and evaporate to dryness on a steam bath. To the residue add 3-5 drops of ethanol, 2-3 drops of furfural reagent, and 1-2 drops of hydrochloric acid. Evaporate to dryness on a steam bath and to the residue add 1-2 drops of acid reagent. Observe the appearance of an intense purplish red residue which dissolves in the acid reagent upon swirling of the dish.

 

The Selivanoff's test :     Its a test for fructose.

 

To the sample is added an equal volume of hydrochloric acid containing resorcinol in the following proportion: 5 mg resorcinol, 5 mL water, and 5 mL 25 per cent concentrated hydrochloric acid. Formation of a dark red color after boiling for 10 seconds indicates fructose.

 

The pinoff test is used to find the presence of fructose.

 

 

Njoy!