- You know that icy chill feeling in your mouth when you're chewing minty gum or the blistering sweat inducing heat you feel when you bite into a hot pepper.

These foods aren't changing the actual temperature in your mouth.

Instead, it's the chemical compounds within these foods triggering a reaction called chemesthesis.

What is chemesthesis?

It's basically your body's ability to sense chemical irritants.

These stream sensations don't fit into what we know as the five basic tastes: bitter, salty, sour, sweet and umami.

But when you take chemesthesis into account, suddenly we begin to see that there's more to taste than just the basic five.

Let's go beyond the basics and expand our pallets.

Or at least, what we know about them.

(upbeat music) It's strange to think that spicy isn't listed as one of the basic five tastes because it is one of the most intense.

But that spicy flavor comes from a mix of feeling heat and pain.

Spicy foods are triggering the same receptors in your mouth that warn you that something is burning.

But don't worry.

Spicy foods will not damage your tongue.

You might be sore after eating a really hot pepper but you're not burning your taste buds off.

There are several chemical compounds that trigger the spicy sensation.

One of the most commonly known is capsaicin which is found in chili peppers.

Capsaicin is what makes your mouth feel like it's on fire.

It's the reason our eyes water and why we begin to sweat.

And the more capsaicin there is, the more intense that burning sensation.

How much capsaicin is present can be measured by the scoville scale.

The higher the scoville heat units, the more potent the pepper.

Jalapeno peppers come in at about 2,500 to 8,000 scoville units.

While the habanero has been measured anywhere around 100,000 to 350,000, depending on which pepper you pick.

For a while, the carolina reaper was one of the hottest peppers at around 2 million on the scoville scale.

But in recent years, the creator of the carolina reaper, Ed Currie, developed a new spicy beast known as Pepper X, which comes in at about 3.1 million scoville units.

The opposite of spicy hot capsaicin would be the cool, cool chill of menthol molecules present in peppermint.

It's working almost the same way as capsaicin by activating our temperature sensors, but it's triggering a different receptor.

Wherever menthol touches, it makes your cold receptors extra sensitive.

Tricking your brain into thinking your mouth is actually colder than it is.

This is why your mouth feels cold and tingly after eating a mint.

Capsaicin and menthol represent two forms of chemesthesis but there are other reactions that cause strange tactile sensations.

One of them is astringency.

An astringent isn't just something that you use to dry your face and tighten your pores.

It's also a flavor that similarly makes your mouth feel dry and tight.

And that puckering astringency is caused by tannins which can be found in certain fruits, teas, coffee, herbs and wine, particularly in red wine.

In fact, in the world of wine, the mouthfeel of tannins is a big part of wine tasting notes.

So the next time you have a glass of wine and your mouth feels a bit dry and rough, you can sound really fancy by saying there are a lot of tannins in this wine.

Carbon dioxide is what gives soda and other carbonated drinks their fizziness.

And for a long time, people suspected that what we were sensing when we drank soda or a glass of champagne were just the tiny bubbles popping in our mouth.

Which is true to an extent, but there are other things happening simultaneously that hint that carbon dioxide is its own taste entirely.

Research suggests that when we drink something with CO2 the taste receptors that are sensing the gas are the same receptors that respond to sour.

The sour receptors create an enzyme that converts the CO2 into bicarbonate ions and free protons.

Those free protons are then detected by our sour sensing receptors in our taste buds.

But why would humans need the ability to taste carbon dioxide?

Science suggests that it might have to do with our evolution.

Fermentation releases CO2.

So our bodies being the beautifully engineered machines that they are, needed the ability to taste when foods were going bad.

Despite possibly being an evolutionary deterrent, fermented foods are very prominent throughout human history.

That's why we have things like wine, beer, bread, yogurt, sauerkraut, kimchi and chocolate.

Humans have been wrangling bacteria for millennia.

The thing is some of the foods and flavors we love the most are developed through fermentation and are possibly made more enjoyable thanks to the presence of CO2.

And it's kind of fun to think that humans intentionally were like, fermentation can be bad.

But if you get that bacteria just right, boom, flavor explosion.

Flavor is complicated and impacted by a variety of sensory inputs.

But if one thing is for sure, it's that eating is made a lot more enjoyable thanks to our ability to experience all of that variety.

So, what describes you?

Are you bitter, salty, sour, sweet or umami?

Tell us in the comments.