Chemical Kinetics for Food Science

This laboratory exercise integrates food chemistry and chemical kinetics through the study of O2 dynamics in a synthetic wine model. Designed for advanced undergraduates, it links redox theory with practical enological applications. Using a noninvasive 2D fluorescence quenching imaging system, students monitor dissolved O2 consumption catalyzed by Fe3+ and Cu2+ complexes in a tartrate-buffered ethanol solution that preserves key chemical features of wine. Students acquire real-time kinetic data and identify two regimes: an induction period at low metal concentrations and rapid O2 depletion at higher loadings, indicating oxidant limitation. These behaviors correlate with Fe3+/Fe2+ and Cu2+/Cu+ catalytic cycles that generate reactive oxygen species. Analysis using initial rates reveals a fractional order in Fe3+ (0.53 ± 0.02), supporting discussion of steady-state intermediates and pre-equilibria, and developing mechanistic insight and data interpretation skills. This experiment also emphasizes reproducibility, uncertainty evaluation, and critical comparison between experimental results and theory.