What the Nose Knows - Avery Gilbert [44]
There is another reason why I think taste is overrated. We are accustomed to experiencing flavor as a singular sensation in the mouth. As a result, we use the words “taste” and “flavor” interchangeably in casual conversation. This makes it easy to forget that flavor is actually a fusion of taste and smell, and that the apparent simplicity of flavor is just an illusion, one that is somtimes reinforced by language. For example, there is only one word for taste and flavor in Spanish (sabor), German (geschmack), and Chinese (wei). I think the tongue gets more credit that it deserves.
That smell makes the far greater contribution to flavor becomes obvious once it is taken out of play. Pinch shut the nostrils, and flavor disappears. What’s left, as the American philosopher and critic Henry T. Finck noted 120 years ago, is bland texture. Caviar tastes like salty oatmeal, and coffee is merely bitter water. This simple, powerful truth is ignored by those who claim the sense of smell is weak and of little importance to modern humans. For example, the pop-science icon Carl Sagan once said “it is clear that smell plays a very minor role in our everyday lives.” Science Digest claimed, “Modern man seldom uses the sense of smell except to detect a burning roast in the oven, or to enjoy a rose bush.” The pioneer sexologist Havelock Ellis had such contempt for smell that he tried to minimize its role in flavor: “If the sense of smell were abolished altogether the life of mankind would continue as before, with little or no sensible modification, though the pleasures of life, and especially of eating and drinking, would be to some extent diminished.” One hesitates to imagine what sort of cramped, joyless inner life could lead a person to write such things, for the reality, made clear by Finck’s demonstration, is that the sense of smell contributes mightily to our enjoyment of food and for this alone deserves to be celebrated.
In his essay on “The Gastronomic Value of Odours,” Finck described a particular type of smelling we use to savor food. He pointed out that aromas released from food in the mouth reach the nasal passages via the back of the throat, and are exhaled through the nostrils. The act of swallowing drives aromas along this reverse path. In effect, we smell our food from the inside out. Today this is known as retronasal olfaction, but I prefer Henry Finck’s name for it: a “second way of smelling,” a phrase that sets it apart from the usual nostrils-first mode. Retronasal olfaction has become a hot topic among sensory scientists, and recent findings confirm Finck’s intuition: the second way of smelling operates by its own set of sensory rules.
THE TWO PHYSICAL paths to the nose—one from the outside world and the other from the mouth—have parallels in the psychology of odor perception. The apparent location of a smell—inside or outside of our body—determines how we perceive it. The psychologist Paul Rozin demonstrated this in a simple experiment. He taught people to recognize the smell of four unusual fruit juices. They sniffed the samples while blindfolded, and quickly learned to tell the them apart with perfect accuracy. When Rozin squirted the same juice samples into their mouths with a syringe, they could not identify them reliably. A smell well-learned when sniffed by the nose is poorly recognized in the mouth. This suggested to Rozin that location has consequences: a food smells one way “out there” and a different way “in here.” The psychological difference between outside-in and inside-out smelling, when combined with taste sensation from the tongue, produces strange contrasts. It makes for foods that smell good but taste bad (coffee, for example), and others that smell bad but taste good (blue cheese).
The psychologist Debra Zellner studies a peculiar