As their name implies, the prime function of these ingredients is to donate flavour which is detected by the senses of taste and smell. Taste itself is made up of the four primary tastes — sweet, sour, salt and bitter — which are detected by the taste buds situated in the mouth, mainly on the tongue, palate and cheeks. Smell is detected by extremely sensitive cells at the top of the nasal cavity. The current standard definition of flavour is as follows: ‘Flavour is the sensation elicited by a foodstuff when the taste and odour receptors are stimulated’.