Electronic Nose Protocol for Authentication of Coffee and Tea A Critical Review of Biomimetic Sensor-Array Technology for Food Authenticity Assurance

Abstract

Coffee and tea are among the most traded and most frequently adulterated agricultural commodities, and their authentication (by species, geographical origin, processing method, and freshness) remains a persistent analytical challenge. This chapter critically examines the electronic nose (e-nose) as a rapidly available, non- destructive protocol for authenticating coffee and tea against adulteration, mislabelling, and quality fraud. It begins by locating the e-nose in the theoretical framework of biomimetic olfaction and multivariate chemometrics, before reviewing a decade of empirical studies applying metal-oxide-semiconductor sensor arrays, pattern recognition algorithms, and machine learning to distinguish coffee varieties, roast levels, and adulterants, and to distinguish tea origins, storage times, and qualities. A generalized protocol (headspace sampling, sensor-array acquisition, chemometric preprocessing, and classification/regression modelling) is presented and evaluated against confirmatory techniques such as gas chromatography–mass spectrometry. The chapter argues that, although e-nose systems routinely achieve high classification accuracies in controlled studies, sensor drift, limited standardization, and restricted transferability impede their adoption to routine regulatory practice. Implications for quality assurance, consumer protection, and policy are discussed, and priority areas for future research identified.