Leave it to noted gourmand and cheese lover Jean Anthelme Brillat-Savarin to deftly capture both the anatomical accuracy and intoxicating romance of experiencing flavor. In his 1825 treatise, Physiologie du Goût (The Physiology of Taste), Brillat-Savarin breaks down the experience of eating a peach:
“He who eats a peach. … is first of all agreeably struck by the perfume which it exhales; he puts a piece of it into his mouth and enjoys a sensation of tart freshness, which invites him to continue; but it is not until the instant of swallowing, when the mouthful passes under his nasal channel, that the full aroma is revealed to him…”
Taste (the tart freshness) is separate from aroma (the exemplification of peachiness). Where taste is experienced on the tongue, aroma is processed in the nasal channel. In the less romantic world of sensory science, this is the process of retronasal olfaction. Retronasal olfaction refers to the aromas you perceive after exhaling while eating, as opposed to orthonasal olfaction, smelling through your nose while inhaling. Breathing while chewing causes some food molecules to react with oxygen in the air; these molecules are then whisked away through the nasal passage. A tangle of hairlike sensors within the passage react to specific compounds and signal the aroma through the olfactory bulb (the hub connecting these sensors) to the hippocampus and amygdala, two regions of the brain closely associated with learning and memory. This process is quite complex, elusive, and mysterious. From a neurobiological perspective, we know very little of how it works. Yet, it is this fanciful flight from the buccal (the technical term for the space within our mouths) to the nasal cavity that has guided the general recommendation to serve cheese at room temperature.
The things we can smell are predominately volatile—they are prone to vaporization. In chemistry, volatility is a measurement of a substance’s ability to turn to gas, from the Latin word volāre (to fly). Our olfactory sensors lie deep in the nasal cavity. In order for us to smell anything, it must be able to soar through the air, and this takes energy. When cheese is removed from the fridge, the surrounding environment transfers its energy into the cheese. In other words: it heats it up. Volatile compounds (the things we can smell) require only a small amount of energy to transform into a gas. Room temperature is often enough.
When we chew a cheese curd or let a decadent triple cream melt on our tongue, the volatile compounds are released and vaporize, wafting through the nasal cavity, exciting our olfactory sensors, and reminding us of past aromas. If the cheese is still cold, fewer compounds take flight and our aromatic experience is diminished, leaving us with only texture and the basic tastes (salt, sweet, sour, bitter, and umami) to incite our delight. Although it takes tremendous self-restraint to leave a cheese alone to temper, the reward will always be a richer and more aromatic journey.
Josh Windsor
Josh Windsor is an affineur and the Senior Caves Manager at Murray’s Cheese in New York City, where he actively nurtures and ages the Cave Aged line of specialty cheeses including the 2019 American Cheese Society (ACS) “Best in Show” winner Stockinghall Clothbound Cheddar and the 2022 World Cheese Awards “Best American Cheese” winner Greensward. Always curious about how cheese ages, Josh is an active member of the community biology lab, Genspace, where he explores the microbial world of cheese rinds. Josh shares his love of all things dairy by teaching cheese appreciation, science, and history at Murray’s Cheese and sensory evaluation at Cornell University’s cheese short courses.