Since early times, flavour compounds ranging from
single to complex substances have been extracted from
plant sources. Eventually, after elucidation of their structure,
synthetic flavours were produced by chemical synthesis.
Nowadays, flavours represent over a quarter of
the world market for food additives and most of the flavouring
compounds are produced via chemical synthesis
or by extraction from natural materials. However, recent
market surveys have shown that consumers prefer foodstuff
that can be labelled as »natural«. Although flavours
may be produced by chemical transformation of