One of the challenges faced by functional perfumery is balancing olfactive intensity and character of a fragrance through each product utilization stage. For a laundry detergent, such stages include directly out of the package (also called “point-of-purchase”), damp cloth immediately after washing, and dry cloth (typically 24 h) after washing. Differences in the intensity or character of a fragrance between stages play an important role in consumer acceptance and likeability.
Researchers at IFF have developed a perfumery tool called iPlots that seeks to measure such intensity and character changes. The tool visually represents intensity and character attributes by simultaneously plotting psychophysical sensory and analytical headspace data. The sensory dose response data provide fragrance character attributes, and the analytically measured headspace concentration data provide fragrance intensity attributes. These attributes can be determined for each product utilization stage.
Sensory dose response curves: The sensory dose response curve of an aroma chemical is a plot of the olfactive intensity as a function of concentration. The curves are typically “S” shaped, as illustrated in Figure 1.