Scientists identify the taste of fat as sixth taste

A group of US scientists believes that fat deserves to be called the sixth taste and have even invented a new name for it: oleogustus.

After sweet, sour, salty and bitter, as well as the most recently acknowledged flavor profile on the palate, umami, scientists from Purdue University in Indiana have published a paper showing that the tongue can also ‘taste’ fat.

Researchers are quick to point out, however, that the taste of fat should not be confused with mouthfeel, or the feel of fat, often described as creamy or smooth.

"Fatty taste itself is not pleasant. When concentrations of fatty acids are high in a food it is typically rejected, as would be the case when a food is rancid. In this instance, the fat taste sensation is a warning to not eat the item,” explained lead author Richard D. Mattes in a statement.

“At the same time, low concentrations of fatty acids in food may add to their appeal just like unpleasant bitter chemicals can enhance the pleasantness of foods like chocolate, coffee and wine."

For the study, scientists asked 102 participants to categorize different solutions aimed at stimulating the six tastes. And even after controlling for odor, texture and appearance, participants were able to group fatty acids together on their own.

To describe the taste sensation, scientists are hoping their newly coined name “oleogustus” -- oleo being the Latin root for oily or fatty and “gustus” referring to taste -- will stick.

The findings were published recently online in Chemical Senses.