Health-care electronic nose to detect beer odor in breath after drinking

Breath analysis is an interesting technique to detect several volatile organic compounds presented within the human body that can indicate the health status of individuals. For this purpose, electronic nose is a convenient device, which is based on a sensor array similar to the olfactory sense as presented in human nose. At present, electronic nose has been widely applied to classify various kinds of odors including those related to healthcare such as breath monitoring. Beer is one of the most popular alcoholic beverages which effects on health and beer odor can be detected in breathing. Beer contains various volatile organic compounds (VOCs) such as ethanol, ethyl acetate and acetaldehyde. In this work, an optical electronic nose that comprises 2 thin films acting as multiple gas sensors (Zinc-5,10,15,20-tetra-phenyl-21H-porphyrin or ZnTPP and Zinc-2,9,16,23-tetra-tert-butyl-29H, 31H-phthalocyanine or ZnTTBPc) were applied to monitor the reduction of alcohol in human breath after drinking of beer. The measurement of VOCs was investigated based on change in the optical absorption of both thin films upon interactions with the breath sample. Principal component analysis (PCA) was used as classification technique to analyze VOCs in form of fingerprint. It was found that the optical electronic nose is capable of tracking alcohol decay in exhaled breath with the passing time.