Classification of food, beverages and perfumes by WO3 thin-film sensors array and pattern recognition techniques

Abstract We have designed and fabricated a sensors array using WO3 thin films operating at the temperature of 180°C for food and perfume analysis purposes. The sensing surface of the rf sputtered WO3 thin films has been differently activated by evaporated Pd, Au, Bi, Sb catalysts. Pattern recognition (PARC) techniques as principal components analysis (PCA) and cluster analysis (CA) have been used in order to classify and identify different classes of flavours samples such as olive oils and seed oils, fruit juices, tomato sauces, perfumes. Good separation among flavours samples belonging to homogeneous and comparable classes has been obtained by PARC methods. The headspace sampling has been referenced off-line by qualitative chromatograms of the volatile compounds constituent the odour under test. The preliminary results show the feasibility of the electronic nose system to discriminate various flavours for food analysis and perfumes quality control.