Molisch test

Molisch Test

The Molisch test is a sensitive chemical test, named after Austrian botanist Hans Molisch, for the presence of carbohydrates, based on the dehydration of the carbohydrate by sulfuric acid to produce an aldehyde, which condenses with two molecules of alpha-naphthol to produce a purple solution.

Procedure

The Molisch test involves the addition of a few drops of Molisch reagent (a solution of alpha-naphthol in ethanol) to the test solution. This is followed by the careful addition of sulfuric acid to form a layer below the test solution. A purple ring at the interface indicates the presence of a carbohydrate.

Applications

The Molisch test is commonly used in biochemistry to detect the presence of carbohydrates in solutions. It is also used in food testing laboratories to confirm the presence of adulterants in food products.

Limitations

While the Molisch test is highly sensitive, it is not specific for any particular carbohydrate. Therefore, it cannot be used to identify a specific carbohydrate in a mixture.

See also

• Benedict's test
• Fehling's test
• Barfoed's test
• Tollens' test