THE TALE OF AN EXOTIC VINE, WOOD PULP, AND A PLEASANTLY SCENTED BEAVER

BY EM HART

Pure vanilla is one of the most complex flavours in the world. Its unique taste and aroma is made up of over 250 organic components. Used in food production, perfume manufacture and aromatherapy, it is also one of our more labour-intensive agricultural crops, and second behind saffron as our most costly spice. Despite the high price—around $US 4,000/kg—global consumption is now well in excess of 2,000 metric tons per year. Demand for this limited resource has driven a switch to imitation products. Why, then, is vanilla so expensive? What are the artificial vanilla-like flavourings used in imitation products? And is a preference for pure extract fully justified, or simply a case of highbrow food snobbery?

TIME IS MONEY

Like many of the world’s rarer commodities, the high price of vanilla is linked to time, availability and the labor-intensiveness of its production. The vanilla pod is the fruit of a tropical orchid, Vanilla plantiflora, which once only grew in its native Mexico. Now it is cultivated throughout the tropics, the transplantation made possible through the development of hand pollination techniques. (The small genus of bee—Melipona—that are the plant’s natural pollinators do not exist outside the orchid’s native home). Despite this expansion, the vine’s need for specific environmental conditions means production is still restricted to a relatively small geographical region, with roughly 80% of the world’s supply now coming exclusively from Madagascar.

Further restricting vanilla’s availability is the number of years it takes from planting before a vine first bears fruit. The yields themselves are also quite conservative. One flower per stalk will bloom each day and will remain open only for that day, meaning significant time and effort must be invested to maximise crop yield. Under perfect conditions a five-year-old vine can produce from one and three kilograms of green pods, which then take between six and eight months to mature.

At this point the pods are individually handpicked and sent for curing, a four-step process that takes a number of months to complete. The pods are killed—usually by immersion in hot water—to halt any vegetative growth that is still occurring. Then they are wrapped in cloth to sweat for 7–10 days, under high heat and humidity. During this stage natural enzymes present in the seed capsule are activated and help drive numerous hydrolytic and oxidative processes that release a number of the aromatic compounds. Among these is vanillin, the major flavour constituent of vanilla. By the end of the sweating process the pods will have attained much of their characteristic colour, aroma and flavour but will still have a high moisture content, so they must be dried. Traditionally performed through intermittent exposure to sunlight, this step helps lock in the aroma and reduces the risk of rotting. Once the moisture content is down to around 25–30% by weight the beans are then conditioned for another 5–6 months, to further develop the fragrance and flavours.

Because harvesting the vanilla plant is so complex and demanding, production still relies on traditional techniques that are highly laborious. This prompts many farmers to sell out and switch to modern-day crops that are more predictable and can be harvested cheaply with the aid of technology. Those persisting with the old ways do so in countries where the systems linking primary producers with traders are becoming increasingly complicated and prone to corruption, making the supply chain inherently unstable and ultimately driving up the final cost.

IS IT A TREE? IS IT A BEAVER?

Humans are an inquisitive bunch. We like to know how stuff works, and while this curiosity has driven countless life-changing discoveries, the value of others has perhaps been not so good (mass-produced sliced white bread, definitely not the best thing!). We also like to be cheap, so if there’s a chance to make something at a fraction of the cost we’ll jump at it, even if it means scrapping the real deal for something vaguely similar that’s completely synthetic.

Vanillin was first isolated as a relatively pure substance in the late 1850s, and within 20 years the first commercial synthesis of it had begun. Derived from the naturally occurring aromatic organic compound eugenol, vanillin was initially isolated from cloves, a common spice commercially harvested and traded throughout Asia, Africa and the Middle East. Synthetic vanillin derived from guaiacol and lignin became widely available during the late 1930s when these compounds became available as a byproduct of the rapidly expanding wood pulping industry. Petrochemicals provided a further source of these and similar compounds—other artificially derived chemicals with vanilla-like flavours used in imitation essence include ethyl-vanillin, propylene glycol, and coumarin (more on that later).

But there was another ‘natural’ substitute. Castoreum, an exudate derived from the anal scent sacs of beavers, is also used in food production as a vanilla flavour substitute. Admittedly, industry consumption of this product is incredibly low (140 kg versus 1.2 million kg of synthetic vanillin) so it serves as little more than a good story. That said, at 60 grams per sac (and presumably a much smaller weight of castoreum) that’s still one hell of a lot of angry beavers! An advantage for manufacturers of castoreum-based vanilla flavor was that an animal-based product could be listed as a ‘natural flavouring’ without requiring further qualification, which brings us to the subject of sneaky labelling.

YOU SAY ESSENCE, I SAY EXTRACT

In the perfume industry the definitions of an essence versus extract are clear-cut: an extract is produced when the scent-containing part of a plant is cold-pressed, macerated or soaked in liquid (usually alcohol); an essence is produced via distillation. But when it comes to vanilla these terms get decidedly hazy. An extract is generally a natural flavour derived from real vanilla pods. Essences are presumed to be chemically synthesised, but can be natural and will usually contain other ingredients. Many companies will include the teeniest of tiny percentages of real vanilla extract in their imitation essence so that they can use ‘natural flavouring’ on their labelling and, as discussed earlier, will add vanillin-like compounds extracted from animals so they can use the term ‘natural’. In addition to those unfortunate beavers, Rhovanil Natural™ was trademarked in the year 2000 as a natural vanillin produced by the action of microorganisms on ferulic acid, a compound extracted from rice bran. Although Rhovanil Natural™ was not considered commercially viable ($700/kg versus $15/kg synthetic vanillin) one big plus was that the industry could state the product contained natural flavouring while leaving the consumers none the wiser as to its source.

For many of us, the choices we’re faced with in the supermarket aisle are mindboggling and the confusion rampant, as to whether a product is an essence or extract, natural or synthetic. While it is generally safe to presumve that imitation vanilla essence is wholly synthetic, the lack of regulation around both production and labelling has in no way helped the consumer. To try and set some standard for the industry, the United States Food and Drug Administration (US FDA) defines vanilla extract as: ‘a solution containing the sapid and odorous principles extractable from 13.35 oz cured vanilla beans and not less than 35% by volume ethyl alcohol in one gallon of finished product (corresponding to a one-fold extraction, being roughly 1:10 ratio of vanilla beans to diluted ethanol), and with a moisture content greater than 25%’—perfectly comprehensible by your average Joe! (And so delicious!). Extracts may also contain one or more of a number of optional ingredients, including: sugar, glycerin, propylene glycol, dextrose, and corn syrup. These extras enhance the colour, sweetness and/or stability of the end product. It is also worth noting that quality grading of vanilla is performed prior to extraction so there is no standard set when it comes to flavour. The grading of vanilla beans is also primarily visual—based on length, appearance and moisture content—so the highest grade may not necessarily be the most flavourful or aromatic anyway.

IMITATION IS NOT ALWAYS FLATTERY

Artificial vanilla is now extremely common, with up to 97% of the market occupied by synthetics. While for many industrially-produced vanillin is an acceptable substitute, the demand for natural vanilla has more recently increased. This is due to a swing back to ‘real’ produce—and thus products claiming to be made with ‘real vanilla beans’—and to a surge in popularity of Western food among countries such as China. Adulteration and counterfeiting is therefore rife, as product fraudsters employ various tactics to pull the wool over the consumers’ eyes. Mislabelling is common—either by falsely stating the country of origin or selling artificial extract as authentic vanilla—as is dilution with ethyl vanillin or other vanilla-like substances. So not only might you not get what you paid for, there are also potentially serious health risks associated with some of these practices. Tonka bean extract, which is sometimes used as a vanilla-like flavouring across Latin America and Mexico, contains coumarin, a fragrant organic chemical that causes the thinning of blood, is moderately toxic to the liver and kidneys, and is banned from foodstuffs in the USA. In addition, artificial vanillins derived naturally from other, non-bean-based materials like rice hulls are increasingly being marketed as ‘natural vanilla flavours’ despite the position of the FDA. As for those fragrant beavers, well, extensive hunting for fur and castor sacs saw a massive decline in beaver populations across Europe, Canada and the USA to the point that we were on the verge of obliterating two entire species. Conservation efforts have since seen numbers recover, and a change in attitude of the world’s fashionistas saw the popularity of the fur trade decline. With fewer beavers being killed for their pelts the availability of castor sacs also decreased, making ‘vanilla flavour’ derived from this process a less viable commodity. Furthermore, with consumers becoming more forthright about product transparency there was a strong surge away from these beaver-based products, people evidently being far less squeamish about eating something that’s been derived from crude oil than an exudate from an animal’s (albeit dubiously positioned) scent gland.

DOES IMITATION MEASURE UP?

In short, no. While vanillin is the major flavour constituent, many of the other volatile compounds present contribute to vanilla’s flavour. Not only does the relative abundance of this key set of volatiles alter the flavour/aroma profile, but the growing conditions and soil nutrition (ie. geographical location), maturity at harvesting, method of ‘killing’, manner of curing, storage conditions, extraction method and age of extract all have an impact on the relative concentrations of the various tastes and flavours. With 249 other components all making their mark, artificial, albeit pure, vanillin is simply no match for the sophisticated, delicate flavour of natural vanilla.

Em Hart is a former research microbiologist and now a baker at Tivoli Road Bakery in Melbourne.

FLAVOUR TERMINOLOGY

The flavour and aroma of vanilla is very complex, with broad array of terms used in describing the specific characteristics it imparts.

Anisic

Balsamic

Barnyard

Caramelised

Chocolate

Creamy

Floral

Hay-like

Prune/raisin

Resinous

Rummy

Smoky

Sweet

Spicy

Tea-like

Tobacco-like

Vanillin

Woody

COMPLEXITY

Pure vanilla is comprised of over 250 compounds that fall into non-volatile (flavour) and volatile (flavour and aroma) categories. Some examples of these include:

VOLATILES: acids, ethers, alcohols, acetals, heterocyclics, phenolics, hydrocarbons, esters, and carbonyls.

NON-VOLATILES: tannins, polyphenols, free amino acids, and resins.

MAKE YOUR OWN

Making your own vanilla extract is easy, so long as you have the patience for it. Take 20–25 split vanilla beans, shove them into a 750 ml bottle of alcohol—being sure to remove some liquid first to help accommodate them (skol!)—and then store in a cool, dark place. Use a neutral alcohol, like vodka. Rum works equally well but will impart a different flavour. Invert the bottle regularly to help distribute the seeds and leave for a minimum of three months before using. The long your extract steeps, the more complex the flavours.