Practical – Testing for Starch Inside Food
Starch is molecule that is found in many different foods
and is made using glucose. Plants use starch as a way of
storing food for later. Photosynthesis is used to obtain
glucose in plants.
Aim: to test for the presence of starch (glucose) in different foods
Equipment: multiple samples of food, Iodine, mortar and pestle, plastic
spoon and plastic plate
Risk assessment:
Risk
Injury
Prevention
Method:
1) Take one small sample of each food and grind them up separately
using the mortar and pestle
2) Place the grinded up sample and place it on to one part of the plate
3) Identify the food and write it in the results table on the back
4) Complete steps 1 – 3 for each of the different foods
5) Place a drop of iodine onto each of the food samples
6) Write down what colour change occurs when the iodine solution
touches the food
Results:
Food Sample What is the food?
Water
What colour does the iodine
change?
Water
1
2
3
4
5
Leaf
Leaf
 If the colour stays the same, then starch is NOT present within the
food / product
 If the colour changes to a darkish / purple / black colour, then
starch IS present within the food / product
Conclusion: Using your results table, write in which products / food have
starch and which do not
Starch is present
Starch is not
present