Study Set Content:
is widely used for the detection of starch in the solution.
Iodine Test
In an iodine test, what acts as an indicator
iodine
The dicarboxylic acid formed from galactose is called
mucic acid
In the Iodine test, an iodine solution reacts with the starch (containing a
polymer of α-amylose and amylopectin
• In the Iodine test, an iodine solution reacts with the starch (containing a polymer of α-amylose and amylopectin. This reaction of starch and iodine results in a starch-iodine complex which give
blue-black color to the solution
The dicarboxylic acid formed from galactose is called mucic acid and is insoluble in
cold aqueous solution
is able to oxidize the terminal groups of aldoses, but leaves the secondary hydroxyl groups unchanged.
Nitric acid
Those acids formed from the other common sugars are soluble in
H20.
Thus the formation of the insoluble precipitate is an indication of the presence of
galactose
Starch color in iodine test
blue
Amylodextrin
Purple color
Erythrodextrin
Red color
Achrodextrin
Colorless
Maltose
Colorless
Glucose/Fructose yields Ethanol and Carbon Dioxide
Fermentation
Molisch's Test
Fehling's Test
Osazone or phenylhydrazine test
• Barfoed’s Test
Mucic acid test
