Middle notes refer to the scent you sense in the perfume (for about 1 to 3 hours). Perfume is released when aromatic components are heated by heat and evaporate into the air. Middle notes are made up of fragrances that evaporate more slowly than top notes, and are typically floral or fruity. They are also called heart notes because they are the longest-lasting fragrance, and perfumers often decide on the composition of the middle notes first. When choosing a perfume in a store, we tend to focus on the top notes when we first apply it, but we recommend letting it sit for a while and then judging whether you like the scent as a whole, including the middle and base notes.