Fig. 2

Odors selected from the chemical space. Odors were chosen from a list of commonly used odors in industry and research provided in Khan et al.⁴ and used for conducting a principal component analysis on a range of physical and chemical properties as described in Bierling et al.²⁶. The position of the molecules chosen for this study in the physico-chemical odor space is indicated as “x”. The red “x” show the two anchor odors used across all groups. Two-dimensional illustrations of the molecules are shown for each group. Molecule names are given as abbreviative forms, see Data Record 2, together with the corresponding CAS number in brackets. Note: The odor tributyrin (set 1, odor number 9) has later been replaced by 2-phenyl ethanol (PEA) due to chemical reactivity with the plastic containers. For the same reason, PEA was used in odor set 3 (odor number 23) instead of the originally chosen odor cuminol (4Isoprop). For details see section “Odor selection”.