Taste bud - Definition and Overview

Taste buds (or lingual papillae) are small structures on the upper surface of the tongue that provide information about the taste of food being eaten.

There are four types of taste buds present in the human tongue.

• Fungiform papillae - as the name suggests, these taste buds are slightly mushroom shaped if looked at in section. These are present mostly at the apex (tip) of the tongue.
• Filiform papillae - these are thin, longer taste buds, and are the most numerous.
• Foliate papillae - these are ridges and grooves towards the posterior part of the tongue.
• Vallate papillae - there are only about 3-14 of these taste buds on most people, and they are present at the back of the oral part of the tongue. They are arranged in a V-shaped row just in front of the sulcus terminalis of the tongue.

There are generally four types of taste sensations in the tongue.

• Sweet and Bitter which works with a signal through a G-protein coupled receptor.
• Salty and Sour which work with ion channels.

There is a fifth taste sensation in the tongue; however, it is still in debate. This taste sensation is called umami, which is believed to be responsible for the savoriness of some foods. The compound glutamate is believed to be the initiator for this taste.