Fundamental study of odor recorder for multicomponent odor using recipe exploration method based on singular value decomposition

A new method for the odor recorder, electronically recording the recipe of odors or scents made up of many components, was proposed. Although apple flavors have been recorded with a mixture of five components using the odor recorder in previous work, the number of odor components should be increased to expand the applicable range of odors. Since the collinearity problem of the odor sensor array became apparent with the increase of components, a new method based on variable transformation using singular value decomposition was developed in this paper, to extract the effective subspace of the sensor outputs for recipe exploration. As a result, the sensor-array response pattern of the reproduced odor, with the eight-component recipe, almost agreed with that of the target apple flavor. Furthermore, human sensory tests revealed that the smell of the approximated odor was identical to that of the target flavor.