Juicing the Juice: A Laboratory-Based Case Study for an Instrumental Analytical Chemistry Course

Abstract

A young, inexperienced Food and Drug Administration (FDA) chemist is asked to distinguish between authentic fresh orange juice and suspected reconstituted orange juice falsely labeled as fresh. In an advanced instrumental analytical chemistry application of this case, inductively coupled plasma (ICP) spectroscopy is used to distinguish between the fresh and reconstituted samples based on their calcium and magnesium concentrations. Students working in teams are given the challenge posed in the case to the FDA chemist. They are charged with designing an experimental procedure, obtaining and analyzing the needed data, and writing a formal report. This case study requires students to conduct themselves in the same manner chemists would in the “real world” when faced with a new and challenging problem. Experimental procedures developed by student teams lead to the correct identification of unknowns a majority of the time. Assessment data indicate this case study elicited positive interest and interactions.