Square wave voltammetry monitoring of unsaturated fatty acids during thermal degradation

Abstract: Ongoing work in our lab is devoted to developing simple, fast, and user-friendly methods for monitoring fatty acid degradation. Specifically, this work focuses on monitoring unsaturated fatty acid degradation in common frying oils during heating. Current instrumentation and methodologies in this field offer various benefits, but there are few truly quantitative methods for assessing frying oil quality. Electrochemical methods offer a unique platform for achieving these goals because of the direct quantitative relationship between analytical signal and sample concentration. The direct stoichiometric relationship between electrons and an analyte undergoing reduction or oxidation is a predictable relationship between measured charge (Coulombs) and mols of analyte. Current research utilizes square-wave voltammetry to monitor fatty acid degradation in vegetable, canola, peanut, and safflower oils. In this presentation, voltammetric signals (oxidation peak currents, fatty acid–oxidation peak identification, and figures of merit) will be compared against complimentary analytical techniques such as FAME analysis via GC-FID. Recent advances in our work have identified unique volumetric signals for oleic acid, linoleic acid, and linolenic acid under our experimental conditions following standard calibration curve analysis. Figures of merit for our methodology will be detailed. Additionally, updated GC-FID data for fatty acid degradation will be compared to previously collected square wave voltammetry studies.