Extraction and Quantitation of FD&C Red Dye #40 from Beverages Containing Cranberry Juice: A College-Level Analytical Chemistry Experiment

A chemical separation experiment can be an interesting addition to an introductory analytical chemistry laboratory course. We have developed an experiment to extract FD&C Red Dye #40 from beverages containing cranberry juice. After extraction, the dye is quantified using colorimetry. The experiment gives students hands-on experience in using solid phase extraction to extract the red dye from other colorants in the red beverages. Students are also given experience with colorimetry, the Beer-Lambert law, and some wet chemical techniques. The recovery of the red dye from spiked cranberry juice was found to be 99% with a standard deviation of 2%.