Food Tests

• Add iodine solution to sample and if starch is present, it will turn to blue/black
• To test for sugars, add Benadict's reagent, if sugar is present, when heated brick/red precipitant will form
• To test for proteins, use Biuret reagent, if protein is present it will turn a purple colour
• If there are no changes in any tests, this means that the food item contains none of these substances.
• To test for Lipids, mix food sample with ethanol and water, if a white emulsion forms, lipids are present