Honey origin authentication using cyclic voltammetry and nanostructured carbon electrodes

Abstract Honey is a sweet substance that bees produce from the nectar of flowers. The geographic origin is an intrinsic factor for the characteristics of honey, which are evaluated through physicochemical analyzes that demand high analysis time and cost. Cyclic voltammetry can be used as an alternative analytical tool for the discrimination of honey samples, being a fast, simple, and inexpensive technique. This study aimed to apply cyclic voltammetry for honey origin authentication from Ortigueira (Paraná – Brazil) using graphite electrodes modified with nanoparticles of nickel oxide, iron oxide, copper oxide, and carbon nanotubes. The voltammograms collected were treated using chemometric methods for exploratory analysis and classification. The principal component analysis (PCA) demonstrated that cyclic voltammetry had better discrimination performance than the physicochemical analysis. The best classification model (PLS-DA) was also obtained with data from cyclic voltammetry with a percentage of correct classification for the prediction set of 94.44%. On the other hand, the PLS-DA model with physicochemical data achieved 88.57% of correct classification in the prediction set. The PLS-DA model using the voltammograms obtained with the developed electrodes showed more accuracy and greater selectivity when compared to the PLS-DA model built with the physicochemical data. Furthermore, the electrochemical system developed has low cost and allows quick analyzes that can be applied to verify the authenticity of the geographical origin of honey samples.