Taste, Smell, Temperature: The Key Ingredients of Flavor
By Mike Howie
Isolate the tongue and it will tell you, basically, how food tastes. But add the sense of smell and you go beyond the simplicity of sweet, salty, bitter, sour, and savory to a world of flavor explaining that yes, this is your favorite brand of gourmet chocolate. Would you like another piece?
But there is more to flavor than just taste and smell: temperature is also a key ingredient.
The Effect of Temperature
Temperature is already closely linked to many foods in our minds. Ice cream? Cold. Coffee? Hot. And we tend to be disappointed when we encounter those foods at the “wrong” temperature. “Come sit down and eat,” many parents have and will continue to say, “your dinner is getting cold.”
But there is truth in the command. Food really can taste different as its temperature changes.
That’s because microscopic channels in our taste buds change the way we perceive taste based on temperature. Dubbed TRPM5, these channels react more strongly to food and drinks at higher temperatures. That reaction is what makes melted ice cream taste sweeter, and why beer and wine taste less bitter when chilled.
TRPM5 also provide scientists and chefs a way to experiment with flavor. By adding something to food that could enhance or inhibit the TRPM5 reaction, they could change the way the food tastes. Perhaps they could make desserts sweeter without needing as much sugar. Or they could make bland chicken saltier. Maybe they could even make vegetables pass the kid taste test.
The Science of Taste
Taste buds, those little pink tongue bumps, pervade the mouth. Each one lives inside a papilla and is made of 10 to 15 cells bunched together. All taste buds can detect all five types of taste, but some specialize and are grouped together.
At the tip of the tongue are up to 400 fungiform papillae, the most common type, with three to five taste buds in each. Along the sides are about 20 foliate papillae, which look like folds and each house several hundred taste buds. And at the back of the tongue, in the form of a V, are about 12 circumvallate papillae, which are big enough to feel and see and can each have thousands of bitter-sensitive taste buds.
At the top of each taste cell are taste pores, finger-like projections that grab and hold taste molecules from food broken down by chewing and saliva. After detecting taste molecules, the taste cells transmit signals through nerve fibers to larger cranial nerves. From there, taste signals are transmitted to multiple parts of the brain, including the base, ventral forebrain, and the dorsal region, where they’re processed.
Overall, the human tongue has about 10,000 taste buds, each one latching onto taste molecules and sending signals to the brain. Pair those with our sense of smell and perception of temperature and we can discriminate between about 100,000 different flavors.
In our primal days, having such an acute sense of taste could have made the difference between life and death. It allowed us to determine whether or not something was safe to eat. It was so important, in fact, that our taste buds evolved to be the only part of the nervous system that can completely regenerate.
And in many ways our sense of taste has shaped our cultures. Certain flavors have the power to take us back to childhood. Others take us on an exotic adventure. Without our taste buds, we wouldn’t be who we are.
