ABSTRACT
This chapter analyses the organoleptic and chemical/instrumental methods for odor measurement and indicates the general shortcomings of the chemical/instrumental methods in comparison with the reference organoleptic method. Odor is a sensation associated with smell, which is hard to quantify. The most successful instrumental methods for the measurement of odor are those using a gas chromatograph. The use of an odor room can also yield misleading results because of natural odors generated by the body and adsorption by clothing. The use of a panel of individuals for the measurement of odor levels statistically eliminates the unreliability of the individual. The use of humans as measurement instruments introduces a variability that is difficult to control. The human sensor is kept in an air-conditioned room into which charcoal-filtered air is blown to maintain a slight positive pressure. The human olfactory system is capable of detecting and identifying a wide variety of chemical structures and giving different responses to different materials.
