Ever wonder why ice cream does not taste sweet when it is frozen, but only when it melts in the mouth? In addition, melted ice cream becomes supersweet, giving that special “ice cream kick”. And what about that warm beer taste? Scientists from Belgium’s Katholieke Universiteit Leuven have an explanation:
Physiologists from the university of Leuven have discovered that this Trpm5-channel in our taste buds is highly sensitive to changes in temperature. At 15°C the channel scarcely opens, whereas at 37°C its sensitivity is more than 100 times higher. The warmer the food or fluid in your mouth, that much stronger will TRPM5 react, and thus that much stronger is the electrical signal sent to the brain. For example, the sweet taste of ice cream will only be perceived when it melts and heats up in the mouth. If you serve the same ice cream warm, then the reaction of TRPM5 in your taste buds is much more intense and the taste of the melted ice cream is much sweeter.
Based on these findings, K.U.Leuven’s researchers now conclude in Nature that TRPM5 lies at the basis of our taste’s sensitivity to temperature. This was also confirmed in experiments on mice: taste responses increased dramatically when the temperature of sweet drinks was increased from 15°C to 37°C. This temperature sensitivity of sweet taste was entirely lacking in genetically altered mice that no longer produced the Trpm5 channel.
This research opens the way to the development of chemical substances influencing the functioning of the Trpm5-channels so as to suppress unpleasant tastes, for example, or to explore completely unprecedented and new taste experiences.