Experiment 1: Test for carbohydrates

Objective

Test the presence of carbohydrates in common food items

 

Materials required:

• Food items: Bread slice, Potato slice, Soaked chickpea seeds
• 3% iodine solution
• Dropper

Procedure:

• Place a bread slice, a potato slice and a few chickpea seeds (with seed coat removed) in separate and clean test tube
• With the help of a dropper, place 2-3 drops of iodine solution on each item
• Note the change in colour and record your observations

Findings:

• Blue-black colour appears on bread slice and potato slice, whereas, chickpea seeds do not show any change in colour.

Conclusions:

• Bread and potato contain starch which gives blue-black in colour on addition of iodine solution. Whereas, chickpea seeds do not contain starch and thus do not show any change in colour.
• Starch is a type of carbohydrate present in many of our food items.
• Carbohydrates are energy-yielding components of food