Paper presented at the IFEAT Int. Conference in Cape Town

It is interesting to note that to this day buchu remains a well-known herbal medicine in South Africaand to some extent in Europe. However, medicinal use today is very small compared to what isconsumed by the international flavour and fragrance industry.As an essential oilAround 1900, buchu was found to produce an essential oil upon steam distillation. With the aroma ofbuchu in a useable form as the essential oil, the interesting flavour and fragrance properties of buchu,found widespread application in formulations in post-WWII Europe, most notably for its cassischaracteristic at certain concentrations.With the advent of modern analytical methods (GC and GC-MS), in the late 1960s, the main flavourcontributing components in buchu oils could be identified successfully. Almost simultaneously in1971, Lamparsky et al (Givaudan) [7] and Sundt et al (Firmenich) [8] independently described thecis/trans-8-mercapto-p-menthan-3-one isomers in buchu oil as the source of its cassis flavour.The chemical nature of these compounds, relatively simple sulphur-containing monoterpenes,facilitated their synthesis from readily available raw materials. In 1971, Firmenich registered a patentdescribing the synthesis of nature identical cis/trans-8-mercapto-p-menthan-3-one [9] . Suddenly buchuoil was no longer required to impart a good cassis aroma, with the result that usage drasticallydecreased and the buchu oil market crashed. This period in buchu’s history saw widespread neglectand removal of the few established buchu plantations that existed to supply the market.However, renewed emphasis on natural flavours and fragrance raw materials in the EU during the1990s created a new demand for buchu oils, the only known natural source of cis/trans-8-mercapto-pmenthan-3-oneand cis/trans-8-acetylthio-p-menthan-3-one.At roughly the same time, EU legislation restricting the use of raw materials that naturally containpulegone came into force, with the result that the popularity of A. crenulata (35-55% pulegone) inflavour and fragrance applications decreased dramatically. On the eve of the introduction of new EUlegislation further restricting the levels of pulegone in flavour and fragrance formulations, this effect isstill observed today in the ever-dwindling sales of pure A. crenulata oils, as well as a perceiveddecline in the demand for A. betulina x A. crenulata (15-40% pulegone) oils.The demand for A. betulina oils, which are low in pulegone but have comparable flavour properties toA. crenulata or A. betulina x A. crenulata oils, thus became unnaturally high around the turn of themillennium, causing production to lag behind and the oil prices to sky-rocket. On the production sidepoorly developed and neglected farming practices, confusion regarding the species of buchu thatshould be propagated, and inconsistent supply and quality issues were added causes in the highhistorical price of buchu oils. This situation, however, has steadily changed for the better in the past 5years.The Buchu Oil Industry TodayWidespread A. betulina (low pulegone) plantings and the modernisation of buchu farming in the past 5years have set the stage for a reliable supply of excellent quality buchu oils.In a response to the high demand for buchu oil, the total available oil volumes are estimated to havealmost doubled between 2003 and 2006, and, based on knowledge of new plantations, production in2008 is likely to reach around 7.5 tonnes. (The grouping of buchu oil exports under “Aromatic plant106