Taste and Temp: Why salts tend to sizzle while confections stay cool
Sage Kumar, Biology, 2023
Revenge is a dish best served cold. Steak is best enjoyed when hot. But why? What determines each food’s optimal serving temperature? Besides the obvious players in dining that are inherently dependent on temperature like texture and consistency, the answer lies in the connections between the brain and the gustatory wing of the peripheral nervous system.
In a 2016 study detailed in ChemSenses by Bo Lu and colleagues involving C57BL/J6-type mice, a relationship between temperature and the chorda tympani nerve response was established by measuring the electrophysiological output of the nerve in response to the subject tasting a specific compound at different temperatures. Twenty-three stimuli were employed, with six compounds representing sweet flavors, 12 for salty, three for sour, one for bitter flavors, and one for umami (a basic taste characterized by inherent savoury notes). By measuring the signal amplitude as a function of temperature for each stimulus, a graph was produced that displayed the optimal temperature for experiencing each flavor type. For example, salts produced a maximal neural response at a peak of 39 degrees Celsius, but sugars and bitter compounds were best received within a slightly lower range of 31 to 39 degrees Celsius and experienced a relatively sharp decline in reception as the temperature surpassed 40 degrees Celsius.
A relationship between temperature and the chorda tympani nerve response was established by measuring the electrophysiological output of the nerve in response to the subject tasting a specific compound at different temperatures.
The results found in Lu et al.’s experiment tend to line up with our own methods of serving food. The power to control the temperature of food not only allowed early humans to avoid foodborne illnesses and prevent tooth decay, it also enabled them to unlock smells and tastes that had never been experienced before. This power set off an evolutionary process that guides us toward certain heat-flavor combinations and rejects others.
While neuro-gustatory science sounds abstract and distant, it influences your everyday life.
While neuro-gustatory science sounds abstract and distant, it influences your everyday life. Bitter flavors found in foods like coffee and tea are often somewhat unpleasant or are at least “acquired” tastes. Since bitterness is maximally experienced at colder temperatures, these beverages tend to be served warm to mask the unpleasant parts of their flavor profiles.
Salty flavors, on the other hand, are best experienced at room temperature or warmed up, while sweet flavors are ideally received at room temperature or slightly below. This explains why most soups and meats are served hot and most desserts are served cold. So the next time you’re downing your daily cup(s) of coffee, thank your nervous system and your barista for coordinating to construct the ultimate taste experience.
DOI: 10.1093/chemse/bjw082
