Odorants were delivered using an air-dilution olfactometer as previously described (Bragulat et al., 2008; Kareken et al., 2004). Three classes of odorants were used: Alcohol odors (AO, each subject’s two most frequently consumed alcoholic drinks), appetitive control odors (ApCO; chocolate and grape juice; McCormick & Company, Inc., Hunt Valley, MD), and non-appetitive odors (NApO) that represented stimuli not normally ingested, or evocative of ingestive behavior. As preliminary experience showed that some subjects found certain odors unpleasant, subjects chose two of four amongst grass, leather, lilac and Douglas fir; International Flavors & Fragrances, Union Beach, NJ). AO were the actual alcoholic drinks “bubbled” (rendered volatile by passing an airstream through the liquid) in two of the olfactometer’s vials. NApO and ApCO were chosen as prior data showed them to be approximately equal in intensity, pleasantness, and representativeness (Bragulat et al., 2008).
