The tongue is covered with small bumps, called taste buds, that are grouped together in areas with different functions. These taste buds react to simple tastes and pass messages to the brain.
Thus, there are distinct regions on the tongue where the main tastes are recognised.
Taste buds on the tip of the tongue detect sweet tastes, and those at the back of the tongue detect bitter tastes. Groups of taste buds at the side of the tongue measure sour and salty tastes. The tastes of any food is a combination of these four basic tastes.
These taste buds or 'flavour receptors, transmit the different taste information as a message to the brain. It is the brain which processes the information and tells us what food is actually in our mouths.
We each have around 10,000 taste buds on our tongues. As we grow older our taste buds become less sensitive. This is one of the reasons why elderly people may no longer enjoy their food so much.
Hot foods tastes better because the heat causes more of the pleasant smells to rise into the nose. These abundant smells contribute to the total taste of food.
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