Basic tastes

Humans appear to be receptive to relatively few chemical species as tastes. This contrasts markedly with the sense of smell where very large numbers of different species can be differentiated.

There were originally thought to be four basic tastes, which are :-

1) Salt which is produced by the presence of [sodium chloride]?. 2) Sweetness which is produced by the presence of one of several sugars. 3) Sourness, which is produced by acridity? 4) Bitterness...which I am not sure about!

In recent years a fifth taste has become widely although not universally accepted. It doesn't actually have a common name, but is sensitivity to monosodium glutamate (MSG).