• 1% iodine solution (from the drugstore)
• Samples of starches – flour, bread, pasta, lightly-coloured cookies
• Samples of fruits - apples, bananas, tomatoes, lemons
• Samples of vegetables including – potatoes, peas, corn, cauliflower, onions

1. Take a small amount of a food that belongs in the bread group and put one or two drops of the iodine solution onto it. What happens?
2. Repeat this with other foods belonging to the bread group.
3. Test small amounts of different foods with the iodine and record what happens.
4. Based on your results, to which food group do peas and corn belong?

When iodine comes into contact with a starch it produces a deep blue (or blackish) colour. We can use the iodine to test whether foods are starches or not.

You can see that all foods in the bread group give a blue colour with iodine-- all starches belong in the bread group. This experiment shows us that some vegetables have a considerable amount of starch in them. They have so much starch that they are usually categorized with the bread group on diet sheets.