P952: Principal component analysis of chocolate

A laboratory suitable for undergraduate instrumental analysis students was developed using VIS/NIR diffuse reflectance spectroscopy to determine the fat content of a variety of chocolate candy bars. This determination used the technique of principal component analysis (PCA) to create a model to interpret that data and then to validate it using other samples. Values were compared with more labor-intensive Soxhlet determinations. Students have been inspired by learning about a non-destructive technique to understand the chemical make-up of chocolate. We have also applied PCA correlation techniques using diffuse reflectance data as a way to quickly characterize the carbon content of soils.