Food Test for Starch
Starch is a carbohydrate, specifically a polymer of glucose. Carbohydrates provide the body with energy. Starch is found in food like potatoes, cassava, maize, and wheat.
To carry out test for starch in a given food sample.
Iodine solution*, water, empty plastic bottle, droppers*, heat source, test tubes*, and a food sample containing starch such as maize our.
Iodine solution is harmful to swallow.
1. Prepare a food sample solution by either saving the water that remains from boiling pasta or potatoes, or by mixing 2 teaspoons of maize our into about a litre of water, then heat up to dissolve and reduce the white appearance of the liquid, which may give students the answer without having to perform the experiment.
1. Place 2 mL of sample solution into a test tube.
2. Add 3 drops of iodine solution to the test tube and record what hap-pens.
When iodine is added, the food sample will change to a blue-black colour. This indicates that the food sample contains starch.
1. Unused iodine solution should be stored in a labeled reagent bottle.
2. No special disposal is required for waste from this activity.