Absent in the wild, Tahitian vanilla (V. tahitensis) is the more expensive of only two vanilla varieties currently cultivated commercially, the other being the more widely used V. planifolia.
As a result, Tahitian vanilla beans are predominantly used in luxury products, according to the report in this month’s American Journal of Botany.
A team of researchers, led by Pesach Lubinsky from UC Riverside’s Department of Botany and Plant Sciences, have now traced back the Tahaitian vanilla plant’s origins to the tropical forests of Guatemala.
“Resach has demonstrated that Vanilla species can exchange genes quite frequently across species barriers,” said Seung-Chul Kim, co-author on the research paper.
“This provides an opportunity to breed new commercial varieties of vanilla through hybridisation in the future.”
Vanilla is important to a wide variety of food and beverage applications, including candies, syrups, ice cream, soy milk, baked goods and sodas.
The team obtained data from 40 different vanilla species growing worldwide and found that the closest relatives to Tahitian vanilla only grew naturally in the tropical forests of Central America.
As the search was refined to Guatemala, the researchers could still not find any Tahitian vanilla growing wild there. However, when they compared the DNA sequences from both the nucleus and the chloroplast and discovered that Tahitian vanilla would fit the pattern of being a hybrid offspring between V. planifolia and V. odorata.
Lubinsky concluded: “Our DNA analysis corroborates what the historical sources say, namely, that vanilla was a trade item brought to Tahiti by French sailors in the mid-19th century. The French Admiral responsible for introducing vanilla to Tahiti, Alphonse Hamelin, used vanilla cuttings from the Philippines.
“The historical record tells us that vanilla – which isn't native to the Philippines – was previously introduced to the region via the ManilaGalleon trade from the New World, and specifically from Guatemala.”
The evidence of the plant’s changes over time provides greater understanding of the capabilities for hybridising vanilla.
The report said the study “identifies novel crop wild relatives (CWRs) for vanilla, namely V. odorata, which can be used in the improvement of a new generation of vanilla cultivars”.
The global market for vanilla beans has been turbulent in recent years, and prices have ranged from about $20 (€14) a kilo to $300 (€211) a kilo, on the back of a devastating cyclone in Madagascar in 2000, and its political crisis in 2002.
The US is the leading consumer of vanilla. Between 2003 and 2005, the unit import price of vanilla there soared to one of the highest unit values of any agricultural import including meats and poultry only to drop more than 80 per cent the following year, according to the UN’s Food and Agriculture Organization.
Like many other products, vanilla has also suffered more recently from the pressures of high energy costs, with the cost of oil topping $145 a barrel last month.
As a result, many companies switched to synthetic vanillin. The current world demand for natural vanilla is about 40 metric tonnes a year. This is significantly less than the global demand for synthetic vanillin, which currently stands at around 16,000 tonnes a year and costs one-hundredth of the price of the natural product.
Source: American Journal of BotanyAugust 2008, doi: 10.3732/ajb.0800067“Neotropical roots of a Polynesian spice: the hybrid origin of Tahitian vanilla, Vanilla tahitensis (Orchidaceae)”Authors: Pesach Lubinsky, Kennety Cameron, Maria Carmen Molina, Maurice Wong, Sandra Lepers-Andrezejewski, Arturo Gomez-Pompa and Seung-Chul Kim