Wednesday, May 12, 2010
Cell Building Blocks: Testing Food for Starch
Gather a variety of food items (fruits, veggies, crackers, chips, cheese, bread, lunchmeat, condiments, etc.-whatever you can find in your house).
Place a drop of iodine on each food item. If the item contains starch, the iodine will turn black (you may have to wait a minute or two. If there is no starch present, the iodine will remain dark purple/brown. The difference can be subtle... look carefully. Also consider the color of your food choices... it's easier to discern the difference on lighter colored foods.
Have students record data and look for patterns in the items that contain starch and those that don’t (think plants vs. animals).