The common organic compounds provide us with nutrients are sugars and starches, carbohydrates, proteins, and lipids. In this lab, qualitative tests are performed to identify the presence of organic compounds in food using indicators, chemical substances that react in a certain way when a particular substance is present. We put one indicator into the each test tube containing different solutions at a time to see what organic compound is present. The color change in the indicator tells that cornstarch contains starch; honey, lettuce, and fruit juice contain sugar; corn oil contain lipid; and by comparing with the standard for positive identification of the substance, unknown is tested to have protein just as egg white. The result tells what nutrients are in the food, and how to test the unknown substances.
II. Introduction Substances or compounds that supply bodies with energy and building blocks for macro-molecules are called nutrients. Food contains different nutrients that are important to bodies. Carbohydrates, proteins and lipids are organic compounds most important to human. Sugars and starches make up carbohydrates, which are the primary energy source in human bodies. Some starches provide roughage, which helps digestion. Proteins are important for growth and repair. Lipids can supply as much as four times the amount of energy as carbohydrates or proteins. By finding out what kind of nutrients are in different kind of food, we would know what we absorb every day and we can manage our diet and eat more healthily. The objective of this lab is to find out what kind of organic compound is presented in the food by observing the color change of indicator in the solutions. The overall purpose of the lab is to learn more about what kind of organic compounds are in the food, how to test for these organic compounds within these foods, and how to test unknown substances using standard to compare the positive identification. Materials