Trade in spices and other exotic material was a significant driver behind the Age of Exploration. Centuries ago, vanilla was a rare New World flavour and vanilla beans were exotic.
Today we think of vanilla as, well, vanilla. Common. Everyday. Ordinary. We even use the term "vanilla" to mean generic, but it wasn't always thus.
It was 1841 when a 12 year old slave boy named Edmond Albius was studying the vanilla orchid, vanilla planifolia, and worked out how to hand pollinate the flower to produce vanilla beans. He used a stick to push open a flap called the rostellum which allowed him to press the pollen-coated anther against the stigma.
As a result, vanilla growers were no longer dependent on the plants pollinator, the Melipona bee, and the orchids could be grown anywhere. Cultivation expanded to Madagascar and today about 80 per cent of the world's natural vanilla comes from small farms there where farmers still hand pollinate each flower to produce the beans.
Natural vanilla is the second-most expensive spice (after saffron) because it is time consuming and labour intensive to produce the pods. However, despite the expense, vanilla is a major flavouring agent for everything from ice cream to hot coffee to perfumes and the demand has vastly outstripped the available supply of beans.
Indeed, less than one per cent of the world's vanilla flavour comes from vanilla orchids. The vast majority - 85 per cent of the 18,000 metric tons used annually - is obtained from a petrochemical precursor called guaiacol.
Technically, most of the world's vanilla flavouring is composed of vanillin. It is the major chemical component of natural vanilla and was first isolated in 1858. By 1874, chemists had worked out how to synthesize the compound from the glycosides found in pine tree sap. Since vanillin from orchids and vanillin from tree sap have the same chemical composition, their taste is indistinguishable. As a result, synthetic vanillin actually caused a depression in the natural vanilla industry.
Another breakthrough came with the discovery vanillin could be synthesized from coniferyl alcohol found in spruce tree lignin.
Lignin is a mixture of compounds forming an inhomogeneous matrix polymer. It is a rich source of complex organic molecules featuring aromatic rings and extended side chains.
The conversion of coniferyl alcohol to vanillin is straightforward as it is simply a matter of converting an alkene to the carbonyl of an aldehyde. A number of oxidative routes can be utilized and it is a reaction which can be done by second-year organic chemistry students.
As lignin is a waste product for the pulping industry, the ability to utilize the material to make a high-value product helped to spur on a value-added side business of small chemical manufacturing. Today, lignin-derived vanillin still represents about 13 per cent of the market.
But generating vanillin from guaiacol is an even easier chemical transformation so it remains the cheaper and more efficient source of food grade vanillin. Other sources included rice bran, corn sugar and clove oil or eugenol.
Most of us have rarely enjoyed eating natural vanilla, as it is very expensive. Indeed, since the bean contains only two per cent of extractable flavour, the price for real vanilla was a staggering $11,000 per kilogram in 2013. Fungal infections and changing climate have significantly impacted the global supply of the beans.
Adding to the pressure on the vanilla market is a commitment by several large food companies - such as General Mills, Heshey's, Kellogg's and Nestl - to eliminate artificial flavours and other additives from foods sold in North America. And since vanilla is so vanilla it is found in just about everything on the market.
Flavour chemists have been working feverishly to find additional sources of natural vanillin while biologists are working to boost both the quantity and quality of beans generated by the plant. Other researchers are exploring the full spectrum of natural flavours to identify potential other compounds which could be used to substitute for vanilla and still give a vanilla-like flavour.
In the United States, castoreum from the caster sacs of mature beavers has been approved by the FDA as a natural flavouring for food products. It is found in food and beverages as a vanilla substitute, but there are only a limited number of beavers from which the compound can be extracted.
The whole question of flavours and flavour molecules is a difficult one for industry to address. After all, spruce tree lignin is a perfectly natural compound found in every spruce tree but the conversion of the coniferyl alcohol to vanillin renders the compound in the category of synthetic. From a chemical point of view, these classifications do not make much sense.
Given the ubiquity of vanilla in everyday products, the only real answer to having natural flavours is going to be growing more vanilla beans and that means converting more jungles to farmland.
