Introduction The purpose of this experiment is to define and classify macronutrients identify macronutrients in solutions of unknown composition, perform chemical testing methods on foods to test for the presence of macronutrients, and recognize experimental controls. Nutrients are divided into two categories, micronutrients and macronutrients. Micronutrients are required in small quantities and include vitamins and trace minerals. Macronutrients are required daily in large quantities and include carbohydrates, lipids, proteins, water, and some minerals. Carbohydrates are an organic compound comprised of carbon, hydrogen, and oxygen. Carbohydrates store energy in many different forms and comprise some structural compounds. Lipids are a group of naturally occurring molecules including fat, waxes, sterols, fat soluble vitamins, monoglycerols, diglycerides, triglycerides, phospholipids, and more. Lipids store energy, provide structure, and serve as cell membranes. Proteins are large biological molecules consisting of one or more chains of amino acid. Proteins catalyze metabolic reactions, replicate DNA, respond to stimuli, and transport molecules from one location to another.
Hypothesis
The hypothesis being examined here is what the positive tests will be for food sample A and B. The prediction is that food sample A will test positive for sugars because the belief is that the sample is apple juice therefore the sample contains fructose. The prediction for sample B is that it will test positive for lipids protein and sugar. This is the prediction because the belief is that Sample B is milk or cheese therefore containing lactose, fat, and protein.
Methods
Materials: 14 test tubes, 1 test tube rack, 1 paper towel, 5 ml Benedicts solution, .5 ml Iodine solution, 2 ml Biuret reagent, hot plate, samples 1-5, A, and B. Procedure: Obtain materials, Label the test tubes 1-5 ad A and B