Characterizing different-flavored e-cigarette solutions from user-reported sensory attributes and appeal

Scientists and regulators need parsimonious methods of characterizing flavored e-cigarettes which may vary widely in both chemical flavoring constituents and marketing descriptors. This laboratory experiment characterized user-reported appeal and experience of five cross-cutting sensory attributes (sweetness, bitterness, smoothness, harshness, coolness) of 10 common e-cigarette flavors. In a within-subject double-blind single-visit protocol, current nicotine/tobacco product users (N = 119) self-administered a single puff of each e-liquid flavor via a pod-style device and rated its appeal and sensory attributes on 0-100 scales. Custom-manufactured e-liquids, nicotine concentration: M (SD) = 23.4 (0.9) mg/mL, representative of commonly marketed fruit (green apple, strawberry), dessert (dark chocolate, vanilla), mint (peppermint, spearmint), nonmint cooling (menthol, koolada), and tobacco (subtle tobacco, full-flavored tobacco) flavor descriptors were used and their constituents were independently analyzed. Results largely demonstrated that a flavor's sensory attributes concorded with its marketed flavor descriptor. Among the 10 flavors, vanilla was rated sweetest (B[difference vs. mean of 9 other flavors] = 14.44, 95% CI [10.84, 18.03]), full-flavored tobacco was most bitter, B = 8.34, 95% CI [4.73, 11.96], subtle tobacco was most harsh, B = 5.69, 95% CI [1.70, 9.68], and peppermint scored highest in both smoothness, B = 6.98, 95% CI [3.13, 10.82], and coolness, B = 29.25, 95% CI [25.50, 33.01]. Flavors with higher appeal ratings tended to be sweeter, smoother, cooler, and less bitter and harsh. Chemical analysis found numerous flavoring constituents among study products without any clear differentiation of chemicals being present in particular flavor categories, which underscores the utility of using sensory ratings to characterize different-flavored e-cigarettes over and above constituent analyses. Characterizing e-cigarette flavors by subjective sensory attributes may be useful in future research and regulatory activities. (PsycInfo Database Record (c) 2023 APA, all rights reserved).