sulfurous, meaty, vegetable, onion, beefy, roasted, beefy1
1.) The Good Scents Company
2.) Franziska Noe, Johannes Polster, Christiane Geithe, Matthias Kotthoff, Peter Schieberle, and Dietmar Krautwurst OR2M3: A Highly Specific and Narrowly Tuned Human Odorant Receptor for the Sensitive Detection of Onion Key Food Odorant 3-Mercapto-2-methylpentan-1-ol Chemical Senses, 2017, Vol 42, 195–210 doi:10.1093/chemse/bjw118
References for aroma perceptual qualities should not be taken to indicate that the authors of outside studies necessarily assigned aroma notes to the neurons that receive input from any given receptor. Rather, the findings of outside studies often constitute the information on which we base our own perceptual quality assignments.