Lipid Identification Lab Answers

Lipid Identification in Various Substances

Summary: In this experiment my group and I performed a lipid chromatography and a lipid emulsion test. The lipid chromatography would separate the molecules found in the lipid by polarity. The solvent we used in this lab moved the most nonpolar molecules farther away from the point of origin. Rf describes the relationship between the distance moved by pigment and the distance from origin to solvent front. The lipid chromatography taught me that the chromatography spots that are closer to the point of origin (which is also the least nonpolar molecule) were typically phospholipids. The next spot toward the top is likely to be cholesterol, followed by fatty acids and then triglycerides (which is the most nonpolar molecule). The larger the Rf value the less polar the molecule is and the father it is from the origin point. Next we performed an emulsification test to test if if lipids were present in various samples. An emulsification test validates the presence of

Materials used: We used all the equipment listed in the lab manual which include: test tubes, test tube rack, hot plate, parafilm, spatula, scissors, glass rod, and pipets. We also used the following food samples: butter, distilled water, Egg Beaters, Coke, lemon-lime soda, and lemon juice. We included positive and negative controls

Methods: First we heated up the food samples that were solid until they melted and became liquid. Then we started by adding 4 mL of ethanol to each food sample and then shaked it. After the ethanol dissolved with the food sample, we decanted the solution into 4 mL of water in a test tube. Then we waited and observed the result. If a milky white emulsification appeared; then lipids were present. If the solution was colorless, then lipids were not