Sudan IV Test for Lipids

This short, targeted simulation is adapted from the full-length “Introduction to Food Macromolecules” simulation.

Discover the lipids in your food! In this simulation, you will be introduced to the chemical structures of lipids and the importance of lipids within our diets. Begin by examining the unique structure of triglycerides and identifying the features of saturated, unsaturated and trans fats. Then learn how to test for the presence of lipids in food samples using the Sudan IV test.

Jump into your food samples

Begin by jumping inside a block of butter to initiate an animation that explains the chemical building blocks that make up lipids. Discover the molecules which make up fats: glycerol and fatty acids. Observe the esterification reaction between glycerol and fatty acids which forms a triglyceride. Learn the structural differences between saturated, unsaturated, and trans fats. Understand why fats are a solid and oils are a liquid at room temperature with the help of molecular structures. Finally, return to the lab to perform an experiment.

Use the Sudan IV test

You will assay food samples using the Sudan IV test for lipids. A range of food samples have been prepared and their respective solution placed in a test tube. Perform the experiment for each food sample and observe the color change over time. Identify the positive and negative result for the test. Use what you have learnt to determine which food samples contain lipids. Does your friend’s salad contain lipids?

Review your knowledge

Put your knowledge of lipids to the test in quizzes throughout the simulation. Do you know how to change an unsaturated fat into a saturated fat?