The rapid-growing, climbing orchid
vanilla planifolia produces pods of seeds, similar to bean pods.
In its native Mexican environment pollination is by the tiny melipone
bee, but for commercial production outside Mexico hand-pollination is
necessary. The fresh pods do not smell of vanilla as the vanillin is
tied up as the glucoside.
Hot water immersion is used to stop photosynthesis,
and the beans are sun-dried and "sweated" by rolling up in
straw mats at night. This curing process results in enzyme hydrolysis,
releasing vanillin, and the pods become shrivelled and brown. Some of
these are exported at this stage for sale in shops.
Production Methods Summary
Vanillin may be produced from lignin, a component in waste material from the wood pulp industry. The sulphite process, which makes paper from wood or straw, generates waste that contains a mixture of useful materials. Sugars are present and can be fermented to produce alcohols, and the remaining solution can then be processed to make vanillin. Although using a waste product, the process was not very "green" as every 1kg of vanillin also produced over 150kg of waste to be disposed of. For more information on the lignin route, click here
The manufacture of vanillin from agricultural waste is now a real possibility. Research has shown that it can be made from ferulic acid, present in this waste. The conversion can also be achieved using fungi or bacteria rather than conventional chemical reagents. This inevitably means working at much lower temperatures and pressures than many conventional production processes, saving in energy at this stage. Click here to find out more.