mintycool

May 31, 2007 7:53 AM

When I'm chewing a piece of mint gum, and I then take a sip from a cool glass of water, why does it taste icy cold?

Basically, the water tastes *extra* cold with the mint gum - why is this so? What about mint (or relatives of mint, or mint flavoring, etc) makes not-abnormally-cool water taste icy cold in my mouth?

posted by raztaj to food & drink (14 comments total)

There's a Quirks and Quarks (scientific radio show on the CBC in Canada) audio answer to this found here. So if you want to hear a scientist give the answer, here you are!
posted by Meagan at 8:09 AM on May 31, 2007

Chrisbucks - thanks for the reply. I couldn't find any questions in the archive?

But the menthol is in the mint - and the mint does add a certain coolness - but why does adding the water (i guess in my mouth) make it suddenly like - WOAH COLD.
posted by raztaj at 8:09 AM on May 31, 2007

Menthol

as per the link...

"Menthol's ability to chemically trigger cold-sensitive receptors in the skin is responsible for the well known cooling sensation that it provokes when inhaled, eaten, or applied to the skin. Menthol does not cause an actual drop in temperature.[3] In this sense it is similar to capsaicin, the chemical responsible for the spiciness of hot peppers (which stimulates heat sensors, also without causing actual temperature rise)."
posted by chrisbucks at 8:13 AM on May 31, 2007

yeah, here's the previous q from January.
posted by jourman2 at 8:33 AM on May 31, 2007

At a sensory evaluation seminar, I was told that menthol is one of a number of substances (like eucalyptus, ammonia, etc) that stimulates the temperature receptors of the trigeminal nerve. You can get hints of it in certain coffees and wines -- it's sometimes called "breathiness" (since it feels like it's opening up your sinuses).
posted by ourobouros at 8:45 AM on May 31, 2007 [1 favorite]

I asked the question before. It's menthol.
posted by sjuhawk31 at 9:05 AM on May 31, 2007

There's a standard psychology demonstration to show that the sensation of very hot arises from the simultaneous stimulation of nerve endings for cool and warm, consisting of a rod wrapped with two fine little pipes, one of which has cool water flowing through it, and the other warm. When naive subjects grasp the pipe, their hands spring open reflexively as if they'd grasped a steam pipe.

I'd like to explain your observation of a freezing sensation in similar terms, raztaj, as receptors for cool continuing to be stimulated by menthol, followed by stimulation of some other class of receptor.

Maybe it could be a simple as a matter of timing-- that you get a sensation of extreme cold instead of extreme hot if you stimulate cool receptors first and then the warm-- but that's somehow not satisfying. Although I do recall thinking that the liquid nitrogen wart treatment I got once was almost indistinguishable from a hot coal in the first instant.
posted by jamjam at 9:52 AM on May 31, 2007

In this it's like capsaicin, which does the same thing to heat sensors.
posted by Steven C. Den Beste at 11:35 AM on May 31, 2007

Good timing for this question. A group has just created a knockout mouse of the receptor for cold and menthol, proving that the TRPM8 gene is responsible for both. Heres the article, and a news and views summary.
posted by scodger at 12:48 PM on May 31, 2007 [1 favorite]

So if someone takes something with mentol at the same time as something with capsaicin, do they cancel each other out?
posted by CrazyLemonade at 12:53 PM on May 31, 2007

Scodger's second link is particularly interesting, raztaj, one of its latter paragraphs seems to give a name to your sensation of great cold in the absence of it-- "cold allodynia":

The protein also seems to be involved in a condition called 'cold allodynia' in which patients become hypersensitive to cold temperatures.
posted by jamjam at 3:55 PM on May 31, 2007

I was thinking the same thing CrazyLemonade. Someone should do an experiment. For SCIENCE!
posted by quin at 4:49 PM on May 31, 2007

CrazyLemonade: I was curious too, and tried something similar a while back. I was eating a chicken sandwich with spicy sauce so my lips felt like they were burning, and then I applied Carmex a few minutes later. It just seemed to make the tingling stronger - didn't really feel hot or cold, just weird and tingly. It would be interesting to try with food too, just to see if it's any different.
posted by flod logic at 6:43 PM on May 31, 2007

I noticed this too and googled around to find that the answer was the menthol but then I found this water called Mint Water. If you liked the sensation that the gum, followed by the water gave you try this water. It is really refreshing and gives you that zip every time you sip it. Go to: www.metromint.com- if you ask nicely they might send you a free bottle to try out for yourself. Just be sure to stick in the frig to get it good and cold first.
posted by bkeene12 at 7:39 PM on May 31, 2007