Why do mints make your mouth feel cold? And specifically, why does your mouth feel so cold if you eat a few mints and then drink a glass of cold water afterwards?
The feeling of cold from mints is caused by menthol. Menthol affects the TRPM8 receptor on skin and also in the mouth. TRPM8 is also a general cold receptor: so if you are in contact with menthol the receptor reacts just like when you are exposed to cold (Bautista et al., 2007).
The receptor is strongly activated at temperatures below 26 degrees Celsius (Bautista et al., 2007). Drinking water is usually colder than that. So if you ate mints and drink cold water afterwards, the receptor response is even stronger.
Why Does Mint Make Your Breath Feel Cold?
There are some foods that are inherently hot, such as chili peppers. Take a hungry bite from a particularly &lsquohot&rsquo chili and you&rsquoll probably spend the next ten minutes like this:
Then, on the other side of the spectrum, there are foods that are inherently &lsquocold&rsquo, including mint. While we&rsquove already written a post about what makes chili peppers so hot, it&rsquos time to investigate the other extremity of the taste spectrum.
No matter how hot the ambient air is, the moment you suck on a mint candy or chew on a stick of mint gum, the breath you draw feels pleasantly cool. Why is that?
Why Does Mint Make Everything Taste Cold?
We’ve all done it. You’re chewing some chewing gum, reach for your glass of water, take a swig and… whoa. Why does the water taste so cold?
Well, we can safely tell you that it’s not magic. There is some actual science behind it, and it’s kinda cool.
At the heart of the effect is a protein called the transient receptor potential cation channel subfamily M member 8. If you can’t remember that, it’s more simply called TRPM8.
It’s found in our cold-sensing nerve cells, and it’s responsible for moving ions across cell membranes. However, it only activates in cold temperatures, alerting the brain that the temperature has dropped.
It does this by allowing in sodium and calcium ions when it gets colder. This sends a current from the membrane of the nerve cell, and hey presto – the brain knows it's cold.
But it’s not just temperature that triggers TRPM8. Menthol, an organic chemical found in peppermint and mint oils, can also activate TRPM8. We don’t quite know how it does this but, well, it does.
This means that when you eat something minty, which contains menthol, TRPM8 is tricked into opening its doors and lets in sodium and calcium ions. A signal is then incorrectly sent to your brain telling it that the temperature has dropped.
It’s not just when it is ingested, too. Applying menthol to your skin, such as in a shower gel, makes your skin go cold and numb. It’s the same effect taking place here, which can also help reduce inflammation.
Something similar works with hot things, too. Ever wondered why chili peppers make you feel hot? Well, that’s due to compounds called capsaicinoids, which bind to receptors that make your brain respond to pain from heat, causing things like teary eyes and a runny nose. This can also, well, make you feel high.
So the next time you pop that mint in your mouth, just remember that while it might taste great, your poor body is panicking as it thinks the temperature is dropping. A least it makes that gulp of water taste all the more refreshing.
Why Menthol Chills Your Mouth When It’s Not Actually Cold
Try putting an ice-cube in your mouth. The insides of your mouth and tongue instantly turn numb. Hold it in still and you will feel pain. Now try sucking on peppermint. The mint itself is at room temperature, but your mouth instantly feels cold and numb. How did it do that? The answer is menthol, the ingredient that instantly tricks your brain into sensing that the food is cold.
Nerves are the wiring of the brain, carrying information in the form of electric currents. Our nervous system is built to sense changes in temperatures – a whole set of nerves running from our skin to the brain is dedicated to conveying just that information. The receptor protein that senses the change in temperature is called TRPM8 and it is found in all cold-sensing nerve cells.
TRPM8 is a voltage gated ion-channel protein – meaning it allows entry of calcium ions on sensing change in temperature. We don’t exactly understand how TRPM8 does it. Whenever there is a drop in temperature, the voltage on TRPM8 somehow changes and its shape changes so that it allows calcium ions to flow into the nerve cell. This triggers current to flow from the membrane of the nerve cell. This current carrying vital information warns the brain of the temperature fall.
Falling temperatures is not the only factor that switches on TRPM8, though. A waxy crystalline organic chemical, called menthol, found in peppermint and other mint oils, can somehow bind to TRPM8 directly and activate it. In fact, TRPM8 was first discovered as a protein that responds to menthol and later acknowledged for its role in sensing temperature fall.
We have also found other 𠇌ooling chemicals” in nature like eucalyptol and icilin, that act similarly. Peppermint drops fire up TRPM8 in cold-sensing nerves and make your mouth instantly feel cool. Even after you have swallowed, some menthol remains and keeps the nerves activated. Just a sip of water can get the nerves fired up again.
In fact, our nerves have similar proteins to sense hot temperatures as well. Scientists have discovered a protein called TRP-V1 that acts like TRPM8 to sense a rise in temperature. Capsaicin, the chemical that gives hot peppers their zing, directly activates TRP-V1, giving that intense feeling of heat.
Kill That Pain With Cold
Menthol, eucalyptus oil and other cooling agents have long been used to relieve arthritic and other muscle and bone pain. We still don’t understand exactly how it works, but one way it may act is by activating its receptor, TRPM8. Just like your mouth feels numb when you eat peppermint, applying menthol on your skin activates the cold-sensing nerves making the area go numb. Now you no longer feel the pain. Menthol can also bind to another receptor called kappa opioid receptor that can also produce a numbing effect.
Rubbing menthol on aching muscles also causes the nearby blood vessels to widen, increasing blood flow in the area. This is called vasodilation. Blood carries in fresh nutrients to repair the area and carries away any toxic waste generated. Healing happens a lot faster because of this.
Lastly menthol takes away the bad effects of inflammation. The word “inflammation” comes from the Latin word inflammare which means to ignite or be on fire and came to mean this because of its association with the way an injury causes inflammation and a sensation of heat.
Menthol gives a sensation of cooling by activating TRPM8 without any actual fall in temperature in that area. This brings down the inflammation in the area. Of course that is why cooling the injury with ice works as well.
This article was originally published on The Conversation. Read the original article.
Nature is Clever
Menthol is actually tricking the brain into thinking a cough drop is cold or a muscle salve is cooling your skin. In 2001, scientists proved that menthol has the ability to bind to and open up pores or cold- sensitive nerve receptors, a protein called TRPM8. They don’t know exactly how it works but they know it has a role in sensing temperature falls. They believe, by opening up these channels, menthol helps your mouth or skin receive more outside air which is typically quite a bit cooler than the air inside your body or on its surface. Your body’s temperature remains the same, but menthol helps it pull in a cooler feeling.
Why do mints make your mouth feel cold? - Biology
Similar to why peppers taste hot, what’s going on here is there is a chemical in mint, menthol, which is tricking the brain into thinking that the area the menthol is applied to is cold even though in fact, it’s the same as it was before. More specifically, menthol binds with cold-sensitive receptors in your skin these receptors contain things called “ion channels”, in this case TRPM8. The menthol makes these much more sensitive than normal, so they trigger and you feel a cold sensation, even though everything is more or less the same temperature as before.
This extra sensitivity is why when you eat peppermint, which has a relatively high level of menthol, and then you breathe in deeply through your mouth, your mouth feels extra cold. Your cold receptors are reacting much more strongly than they normally would to the air which is cooler than the inside of your mouth.
Menthol is a compound classically obtained from various mint plants, though now is often synthetically produced due to the extreme high demand for menthol in a variety of products. Menthol is a waxy, crystalline substance that is somewhat clear or white. Interestingly, it is actually solid at room temperature and melts just a few degrees above room temperature.
Now for an experiment: Take a Jalapeno pepper and an Altoids Peppermint and eat them at the same time. What happens? … Seriously, someone want to try this and report back? Given that the capsaicin in peppers and the menthol in mint are both effectively fooling the brain into perceiving hot and cold using similar ion channels, despite no actual change in physical temperature, it would seem like that the two may well cancel one another out in the brain (how can one feel hot and cold coming from more or less the same receptors?) or at the least, one would think it would produce a very unique sensation. So do they cancel each other out or does one win-out over the other?
If you liked this article, you might also enjoy our new popular podcast, The BrainFood Show (iTunes, Spotify, Google Play Music, Feed), as well as:
Ask an Expert: Does mint actually cool hot water down?
I was thinking if I can get some background information about this topic.
My hypothesis is: If I put mint in the hot water, then the hot water will cool down.
Variable: Water with mint
Control: Water without mint
Constants: The amount of hot water, the temperature, and the amount of mint in each glass of hot water
Please respond as soon as possible
Re: Does mint actually cool hot water down?
Post by allisontu » Tue Dec 27, 2016 12:14 pm
This is a really interesting topic! Your hypothesis, variables, control, and constants all look good.
The compound that makes mint flavoring feel like your mouth is cold is called menthol. I've included a link below for background information.
You can see that this topic is pretty widely researched, but it's still an interesting topic and a good experiment.
Hope this helped and let us know if you have more questions,
How Peppermint Tricks Us Into Feeling (Deliciously) Cold
We seem to be hard-wired to enjoy the refreshing, cooling sensation of menthol in our mouths.
Allison Dinner/the food passi/Corbis
Even in the coldest months, we relish the refreshing, icy taste of peppermint — in seasonal treats like peppermint bark, peppermint schnapps, even peppermint beer.
We have the chemical menthol to thank for that deliciously cool mouth-feel of peppermint. And scientists now know that menthol actually tricks our brains and mouths into the cool sensation because menthol activates the same receptor on nerve endings that's involved in sensing cold, says David McKemy, a neurobiologist at the University of Southern California.
As McKemy explains in a video about peppermint out this month from USC, thanks to this neat trick of nature, researchers were able to use menthol to better understand how our nervous system senses and reacts to cold. His team found a protein which is "a trigger on cold sensing nerve fibers to send an electrical signal to the brain to let you know that you're feeling cold."
Mint-flavored candies date back hundreds of years in Europe and perhaps longer in the Middle East, according to Ryan Berley, owner of Shane Confectionery in Philadelphia. Denise Sutherland/ImageZoo/Corbis hide caption
Mint-flavored candies date back hundreds of years in Europe and perhaps longer in the Middle East, according to Ryan Berley, owner of Shane Confectionery in Philadelphia.
"It's incredible how nature and plants have evolved to have these effects," McKemy tells The Salt.
For some reason, we seem to be hard-wired to enjoy the refreshing, cooling sensation of menthol in our mouths. Research shows that menthol's effects on cold receptors may satiate thirst, ease breathing and help us feel alert — which helps explain why it's so popular not just in candy but also in cigarettes and cold medicine.
As McKemy notes, cold drinks can satiate thirst faster than water that's room temperature, and it is easier to breath when the air is cool. A 1990 study by psychologists found that peppermint may also help us feel more alert and focused.
The reason we got hooked on candy canes and other peppermint treats this time of year is most likely cultural – and coincidental, says Ryan Berley, owner of Shane Confectionery in Philadelphia, where handmade peppermint candy canes sell by the hundreds in the wintertime. Berley researched the history of peppermint candy for an exhibition on sugar and confections he curated last year at Philadelphia's Independence Seaport Museum
Does Mint Actually Cool Things Down?
Mint is a flowering herb, and there are many different kinds of mint. It grows in cool and moist areas where there is shade.
Many people enjoy the light, fresh taste of mint. Mint-flavored gum, breath fresheners, and hard candies often advertise that mint has a cooling effect, and use images of frost and ice to demonstrate this sensation. But is this sensation a result of the mint actually lowering temperatures?
Does mint, known for its cooling effect, really lower temperatures, or is it just a sensation?
- Pack of regular mints (Altoids, Tic-Tac, Mentos, etc.)
- 2 glasses of hot water
- Pen and paper for notes
- Get a glass of hot water and take the temperature with a thermometer. Record this.
- Place 5 mints in the glass of hot water and take the temperature again. Was there a change?
- Place more mints in the glass of hot water 5 at a time and record whether you see any change at all. You should monitor it for 30 minutes.
- The other glass of hot water is to be used as a reference. This is because we know that water cools over time and we want to make sure that if there is any change in temperature, it is not independent of time, but of the mints speeding up the cooling process.
- Record your results. Any changes?
Disclaimer and Safety Precautions
Warning is hereby given that not all Project Ideas are appropriate for all individuals or in all circumstances. Implementation of any Science Project Idea should be undertaken only in appropriate settings and with appropriate parental or other supervision. Reading and following the safety precautions of all materials used in a project is the sole responsibility of each individual. For further information, consult your state's handbook of Science Safety.
How To Get Rid Of The Cooling Effect Or Erythritol
The only way to really get rid of the cooling effect of erythritol is to dissolve it in water first. Of course, this might work great for sweet tea or coffee but not necessarily for many other keto recipes. There have been countless recipes where I had to do a lot of trial and error to minimize the cooling effect.
In addition, there have been plenty of keto desserts recipes I simply had to give up on because the cooling effect was so strong. I would rather have fewer great recipes than to put out a recipe that was not up to a certain standard. Truth be told, I believe there are some recipes that you simply cannot make into a great keto recipe using erythritol. That is, of course, unless you like a hint of mint in all of your baked goods .
That said, let’s talk about the good news. First of all, there are plenty of keto recipes where the cooling effect is almost unnoticeable. This is especially true in recipes that use a lot of liquids and fats. For example, I have never noticed a cooling effect in any of my keto ice cream recipes. Perhaps it is because ice cream is already cold, but also because they contain high amounts of liquid and fat.
Keto desserts made with cream cheese such as cheesecake are also great desserts to bake using erythritol. However, for other desserts, there are still things you can do to minimize the cooling effect. First off, you can simply reduce the amount of erythritol you use in your recipes. You can also add more liquids and fats to your recipes as well.
For example, I had noticed that my chewy keto chocolate chip cookies had less of a cooling effect than my original or crunchy low-carb chocolate chip cookies. This is simply because I added cream cheese to my chewy chocolate chip cookies in order for them to stay extra chewy. In addition, they seemed to have a less pronounced minty taste.
This could all just be in my head, but mixing the erythritol into the wet ingredients first seems to help as well. Lastly, some people say that doing a mix of erythritol and stevia together helps to minimize the cooling effect of erythritol as well as the aftertaste of stevia.
Do Other Keto Sweeteners Have A Cooling Effect?
As mentioned previously, there are other keto friendly sweeteners that do produce a cooling effect. The most common example would be stevia. Stevia has been a great keto friendly sugar substitute for a very long time. However, stevia does contain a pretty powerful aftertaste that is not too pleasant. Personally, I would rather just deal with the minty aftertaste myself.
In addition, stevia is 200+ times sweeter than table sugar. This can make it hard to experiment with since about 1 tsp of stevia liquid extract is enough to replace one cup of sugar. Of course, you could always do the math and there are plenty of conversion charts online, but it is still a hassle.
There are also brands that carry powdered stevia for baking. However, since stevia is so strong, the powder must have an added filler. Often times the filler is just plain old sugar. So yes, it has fewer calories and carbs than pure sugar but is still not the best option for a ketogenic diet.
Another common ingredient that these powdered stevia brands add in is erythritol. In fact, if you read the back of many stevia products the number one ingredient is erythritol. Not to say that these are bad products, just that it does not really do much in the efforts to reduce the cooling effect associated with keto sweeteners.
The same goes for monk fruit as well. Monk fruit is also much sweeter than sugar and is often found in mixes containing erythritol. However, you may notice a difference when using an erythritol mix. My favorite would probably have to be Lakanto Monk Fruit Sweetener . It is made from a mixture of erythritol and monk fruit extract and measures cup for cup with table sugar.
Another common low-carb sugar substitute is xylitol. Unfortunately, xylitol also to produces a similar cooling effect as erythritol. Also, many people report stomach discomfort from consuming too much xylitol. This has been also been reported with erythritol but it does not seem to be quite as common. Xylitol is also very toxic to dogs so be careful where you store it if you decide to try it in any of your recipes.
With some recipes, there just might not be a way around experiencing some of the cooling effects of baking with erythritol. However, there are plenty of keto dessert recipes on this site as well as all across the internet that use erythritol and taste amazing.
By using some of these tips you can greatly reduce the cooling effect you experience baking with sugar alcohols. However, if you really can’t stand the minty taste I recommend sticking to the recipes best suited for baking with erythritol.