Date: ____________________________ Name:____________________________ Partners Names: ____________________________ Lab: Testing For Nutrients in Food PURPOSE: To determine _________________________________________________________________________________________ __________________________________________________________________________________________________ ____________________ HYPOTHESIS: If carbohydrate is present ___________________________________ will turn _________________________________. If a monosaccharide /disaccharide is present ________________________________ will turn ______________________________. If proteins are present _____________________________________will turn ___________________________________. If lipids are present ________________________________________ will turn _____________________________________. MATERIALS: Refer to Textbook: 38-39 with modifications Main Items: Lugol’s solution (iodine), benedict’s solution, biuret solution, paper towel, many food items, test tubes, hot plate, water, 500 mL beakers PROCEDURE: Refer to Textbook: 38-39 Method / Modifications to the Lab Procedure:_____________________________________________________ __________________________________________________________________________________________ __________________ OBSERVATIONS: Results for nutrients found in certain foods. Food Item Carbohydrate Simple Carb Lugol’s soln/iodine mono/dissaccharide Benedict’s Solution Proteins Lipids draw Lipids circles: compare to water on Biuret paper towel Sudan IV Glucose Sucrose Oil Butter Cracker Potato Bread Albumin Milk Banana - unknown Yogurt - unknown Nut butter - unknown Reference Table Indicator Nutrient Testing For Positive Result (+) Negative Result Iodine Carbohydrate Turns black stays red/brown Benedict’s Solution Sugar Turns orange/red green or no change Biuret Solution Proteins Pink or purple blue Paper Towel Fats dries clear dries normal Sudan IV Fats Turns brick red (orange-red) Stays dark red DISCUSSION: pg 39 Answer quesstions g), j), k) l), n) AND the questions below... 1. Were any of the food items positive for more than one nutrient? Why do you think this is? 2. Were there any food items that were positive for a nutrient you did not expect? Give examples. 3. Were there any food items that were not positive for a nutrient you thought would be there? Give examples. 4. a) Compare identifying types of macromolecules using indicator dropper bottles to using diagrams showing the functional groups of each of the molecules. Which would likely be more accurate? Give reasons for your answer. b) In a 2-3 paragraphs explain how you would identify carbohydrates, lipids, proteins and nucleic acids if you were given the functional groups (combination and arrangement of elements in each solution). Refer to the group exercise we did in class. CONCLUSION: - Restate your purpose. - Which macromolecules did the uncategorized food items contain and indicate the tests that told you this.