The volatile substances in tea leaves are largely responsible for a tea’s flavour and aroma. The aroma complex of tea is made up of hundreds of flavour and aroma compounds that exist in trace amounts. Many of these aromatic compounds do not exist in fresh tea leaves and are derived from other substances during processing. The flavour and aroma of each tea depends on a wide variety of combinations of these compounds, hence the name aroma complex. Compounds such as, linalool and linalool oxide are responsible for sweetness; geraniol and phenylacetaldehyde are responsible for floral aromas; nerolidol, benzaldehyde, methyl salicylate, and phenyl ethanol are responsible for fruity flavors; and trans-2-hexenal, n-hexanal, cis-3-hexenol, and b-ionone are responsible for a tea’s fresh flavor.