Capsaicin determination and chili sauce discrimination using low-cost and portable electrochemical sensors based on all graphite pencil electrodes

We developed an electrochemical cell based on all graphite pencil electrodes (GPEs) for the detection of capsaicin. The cell produced a larger detection range of 0.1-100 mu M compared to other reported studies, which is necessary for real sample testing. In addition, the cell was adopted for the analysis of capsaicinoid contents in chili powder and sauces bought from the supermarket. Through data processing by principal component analysis (PCA) and kappa-means clustering, it is possible to differentiate between the different brands of chili sauce. The low-cost and small construction of the cell may lead to a portable electronic tongue for on-site analysis of chili products.