We don't know which receptor responds to which taste. There's many different things that taste bitter. It becomes a puzzle how you can taste so many bitter things with so few receptors. Mueller said the combination of receptors may form a code that the brain interprets to differentiate flavors. But taste can be highly subjective, said Steve Hagata, a winemaker at Falkner Winery in Temecula.
People do tend to agree.
The term fruity refers to sweet wine, Hagata said, while dry wine tastes sour to the novice wine drinker. He said wines are rarely salty unless they have a high mineral content, but red wines can be bitter due to grape seeds. While few people disagree on such general designations, people do describe particular wines in varying ways. Hagata said wine tasters perceive flavors from pineapple and bell pepper to leather and oak. He said the sense of smell, which scientists say uses many more receptors, also plays an important role in the tasting experience.