Comparison of qNMR Spectroscopy and an Enzyme-Based Standard Method for the Determination of Ethanol in Nonalcoholic Beer

The concept of using appropriate statistical methods to compare results from a newly proposed analytical method to a standard method can be poorly understood among undergraduate students. We developed a learning activity for an undergraduate analytical chemistry course to provide a practical demonstration of method comparison. The activity consists of students collecting data on the ethanol content of nonalcoholic beers via a quantitative NMR spectroscopic method, using a benchtop NMR, and an enzyme-based UV spectrophotometric method using a commercially available enzyme assay kit. Students are then able to apply a simple statistical test to determine whether the two methods are equivalent. The activity was successfully incorporated into a course. Students were able to measure ethanol concentrations using both methods and compare data using a Student's t-test. Survey results indicate that the students gained a better understanding of the use of statistics in evaluating an analytical method.