The human tongue is capable of distinguishing just four basic tastes. Its surface is covered by thousands of nerve endings called taste buds, which are divided into four different groups.

    Thos on the tip of the tongue sense sweetness and those at the back sense bitterness. The ones at the sides sense saltiness and sourness. There are other taste buds scattered around the inside of the mouth. The main tasters of sour and bitter are actually in the roof of the mouth.

    So things like honey and sugar are tasted with the tip of the tongue. However beer, which can have a bitter taste, is best enjoyed with the back of the tongue. Specialist beer tasters will tell you to drink it by pouring it to the back of your tongue, avoiding the tip. Salty crisps and chips are tasted by the side of the mouth and things like sour lemons, vinegar and things like that also get tasted by the taste buds at the sides.

    More complex tastes are made up of combinations of the basic four flavours. Young adults have around 8000 taste buds, but the nerve endings start to die after the age of 45, so that older people usually have only around 6500 taste buds.

    Much of what we perceive as flavour in food is in fact a mixture of taste and smell, which is why food seems to lose its taste when the nose is blocked during a cold.

    Damage to taste buds can be very painful and make it very difficult to taste food properly. Even those very tiny ulcers that sometimes affect the tongue can badly affect the ability to taste.

    人類的舌頭只能區(qū)別四種基本的味道。它的表面覆蓋著成千上萬個稱為味蕾得神經(jīng)末梢，分為四個不同的組。

    在舌尖的味蕾感覺甜味，在舌根的味蕾感覺苦味。側(cè)面的一些感覺咸味和酸味。還有其它一些味蕾散落在嘴內(nèi)。嘗到酸味和苦味的主要地方實際上是在上顎。

    所以，像蜂蜜和糖之類的東西是用舌尖嘗到的。然而啤酒，它可能有苦味，最好用舌根來享用。啤酒品酒專家會告訴你將啤酒倒到舌根來飲用啤酒，避免碰到舌尖。咸的薯片和薯條用嘴的側(cè)面來品嘗，而酸檸檬、醋之類的東西以及像它們那樣的東西也由邊上的味蕾來嘗味。

    更為復雜的味道都是由基本的四種口味組合而成的。年輕的成年人具有大約 8,000 個味蕾，但是在 45 歲以后，神經(jīng)末梢開始死亡，所以，老年人通常只有大約 6,500 個味蕾。

    大多數(shù)我們察覺到的食品的香味實際上是味道和氣味的混合，這就是為什麼在感冒期間鼻子堵塞時食物似乎失去了它的味道的原因。

    味蕾損傷會是非常痛苦的，使它非常難以正確地品嘗食物。甚至那些有時影響舌頭的非常微小的潰瘍，都可能嚴重影響味覺能力。