Chocolate is one of the most-consumed treats around the world, and the smell alone is usually enough to evoke strong cravings from even the most disciplined eaters. Much like a fine wine, high-quality dark chocolate has a multi-layered scent and flavor, with notes of vanilla, banana or vinegar. Now, researchers report in ACS’ Journal of Agricultural and Food Chemistry which substances—and how much of them—make up this heavenly aroma.