See P. Rain, Vanilla (2004).
Vanilla is a flavoring derived from orchids of the genus Vanilla native to Mexico. Etymologically, vanilla derives from the Spanish word "vainilla", little pod. Originally cultivated by Pre-Colombian Mesoamerican peoples, Spanish conquistador Hernán Cortés is credited with introducing both the spice and chocolate to Europe in the 1520s. Attempts to cultivate the vanilla plant outside Mexico and Central America proved futile because of the symbiotic relationship between the tlilxochitl vine that produced the vanilla orchid and the local species of Melipona bee; it wasn't until 1837 that Belgian botanist Charles François Antoine Morren discovered this fact and pioneered a method of artificially pollinating the plant. Unfortunately, the method proved financially unworkable and was not deployed commercially. In 1841, a 12-year-old French-owned slave by the name of Edmond Albius, who lived on Île Bourbon, discovered the plant could be hand pollinated, allowing global cultivation of the plant.
There are currently three major cultivars of vanilla grown globally, all derived from a species originally found in Mesoamerica, including parts modern day Mexico. The various subspecies are Vanilla planifolia (V. planifolia, syn. V. fragrans), grown on Madagascar, Réunion and other tropical areas along the Indian Ocean; V. tahitensis, grown in the South Pacific; and V. pompona, found in the West Indies, Central and South America. The majority of the world's vanilla that is produced is the V. planifolia variety, more commonly known as "Madagascar-Bourbon" vanilla, which is produced in a small region of the east African nation of Madagascar and in Indonesia.
Vanilla is the second most expensive spice after saffron, due the extensive labor required to grow the seed pods used in its manufacture. Despite the expense, it is highly valued for its flavor which author Frederic Rosengarten, Jr. described in The Book of Spices as "pure, spicy, and delicate" and its complex floral aroma depicted as a "peculiar bouquet." Regardless of its high cost, vanilla is widely used in both commercial and domestic baking, perfume manufacture and aroma therapy.
In the fifteenth century, Aztecs from the central highlands of Mexico conquered the Totonacs, and the conquerors soon developed a taste for the vanilla bean. They named the bean "tlilxochitl", or "black flower", after the mature bean, which shrivels and turns black shortly after it is picked. After they were subjected to the Aztecs the Totonacs paid their tribute by sending vanilla beans to the Aztec capital, Tenochtitlan.
Vanilla was completely unknown in the Old World before Columbus. Spanish explorers who arrived on the Gulf Coast of Mexico in the early sixteenth century gave vanilla its name. The Spanish and Portuguese sailors and explorers brought vanilla into Africa and Asia in the 16th century. They called it vainilla, or "little pod", The word vanilla entered the English language in the 1754, when the botanist Willow Ewing wrote about the genus in his Gardener’s Dictionary.
Until the mid-19th century, Mexico was the chief producer of vanilla. In 1819, however, French entrepreneurs shipped vanilla beans to the Réunion and Mauritius islands with the hope of producing vanilla there. After Edmond Albius, a 12-year-old slave from Réunion Island, discovered how to pollinate the flowers quickly by hand, the pods began to thrive. Soon the tropical orchids were sent from Réunion Island to the Comoros Islands and Madagascar along with instructions for pollinating them. By 1898, Madagascar, Réunion, and the Comoros Islands produced 200 metric tons of vanilla beans, about 80% of world production.
The market price of vanilla rose dramatically in the late 1970s, due to a typhoon. Prices stayed stable at this level through the early 1980s despite the pressure of recently introduced Indonesian vanilla. In the mid-1980s, the cartel that had controlled vanilla prices and distribution since its creation in 1930 disbanded. Prices dropped 70% over the next few years, to nearly US$20 per kilo. This changed, due to typhoon Huddah, which struck early in the year 2000. The typhoon, political instability, and poor weather in the third year drove vanilla prices to an astonishing US$500 per kilo in 2004, bringing new countries into the vanilla industry. A good crop, coupled with decreased demand caused by the production of imitation vanilla, has pushed the market price down to the $40 per kilo range in the middle of 2005.
Madagascar (mostly the fertile region of Sava) accounts for half of the global production of vanilla. Mexico, once the leading producer of natural vanilla with an annual 500 tons, produced only 10 tons of vanilla in 2006. An estimated 95% of “vanilla” products actually contain artificial vanillin, produced from lignin.
The main species harvested for vanillin is Vanilla planifolia. Although it is native to Mexico, it is now widely grown throughout the tropics. Madagascar is the world's largest producer. Additional sources include Vanilla pompona and Vanilla tahitiensis (grown in Tahiti and Niue), although the vanillin content of these species is much less than Vanilla planifolia.
Vanilla grows as a vine, climbing up an existing tree (also called a tutor), pole, or other support. It can be grown in a wood (on trees), in a plantation (on trees or poles), or in a "shader", in increasing orders of productivity. Its growth environment is referred to as its terroir and includes not only the adjacent plants, but also the climate, geography and local geology. Left alone, it will grow as high as possible on the support, with few flowers. Every year, growers fold the higher parts of the plant downwards so that the plant stays at heights accessible by a standing human. This also greatly stimulates flowering.
The distinctively flavored compounds are found in the fruit, which results from the pollination of the flower. One flower produces one fruit. Vanilla planifolia flowers are hermaphroditic: they carry both male (anther) and female (stigma) organs; however, to avoid self-pollination, a membrane separates those organs. The flowers can only be naturally pollinated by a specific Melipone bee found in Mexico (abeja de monte or mountain bee). This bee provided Mexico with a 300 year long monopoly on Vanilla production, from the time it was first discovered by Europeans and the French first transplanted the vines to their overseas colonies, until a substitute was found for the bees. The vines would grow, but would not fruit outside of Mexico. Growers tried to bring this bee into other growing locales, to no avail. The only way to produce fruits without the bees is artificial pollination. And today, even in Mexico, hand pollination is used extensively.
In 1836, botanist Charles François Antoine Morren was drinking coffee on a patio in Papantla (in Veracruz, Mexico) and noticed black bees flying around the vanilla flowers next to his table. He watched their actions closely as they would land and work their way under a flap inside the flower, transferring pollen in the process. Within hours the flowers closed and several days later Morren noticed vanilla pods beginning to form. Morren immediately began experimenting with hand pollination. A few years later in 1841, a simple and efficient artificial hand pollination method was developed by a 12-year-old slave named Edmond Albius on Réunion: a method still used today. Using a beveled sliver of bamboo, an agricultural worker lifts the membrane separating the anther and the stigma, then, using his thumb, transfers the pollen from the anther to the stigma. The flower, self-pollinated, will then produce a fruit. The vanilla flower lasts about one day, sometimes less, and so, growers have to inspect their plantations every day for open flowers, a labor-intensive task.
The fruit (a seed capsule), if left on the plant, will ripen and open at the end; as it dries, the phenolic compounds crystallize giving the beans a diamond-dusted appearance which the French call givre (hoarfrost). It will then release the distinctive vanilla smell. The fruit contains tiny, flavorless seeds. In dishes prepared with whole natural vanilla, these seeds are recognizable as black specks.
Like other orchids' seeds, vanilla seed will not germinate without the presence of certain mycorrhizal fungi. Instead, growers reproduce the plant by cutting: they remove sections of the vine with six or more leaf nodes, a root opposite each leaf. The two lower leaves are removed, and this area is buried in loose soil at the base of a support. The remaining upper roots will cling to the support, and often grow down into the soil. Growth is rapid under good conditions.
The term French vanilla is not a type of vanilla, but is often used to designate preparations that have a strong vanilla aroma, and contain vanilla grains. The name originates from the French style of making ice cream custard base with vanilla pods, cream, and egg yolks. Inclusion of vanilla varietals from any of the former or current French dependencies noted for their exports may in fact be a part of the flavoring, though it may often be coincidental. Alternatively, French vanilla is taken to refer to a vanilla-custard flavor. Syrup labeled as French vanilla may include hazelnut, custard, caramel or butterscotch flavors in addition to vanilla.
Though there are many compounds present in the extracts of vanilla, the compound vanillin (4-hydroxy-3-methoxybenzaldehyde) is primarily responsible for the characteristic flavor and smell of vanilla. Another minor component of vanilla essential oil is piperonal (heliotropin). Piperonal and other substances affect the odor of natural vanilla. Vanillin was first isolated from vanilla pods by Gobley in 1858. By 1874, it had been obtained from glycosides of pine tree sap, temporarily causing a depression in the natural vanilla industry.
Vanilla essence comes in two forms. Real seedpod extract is an extremely complicated mixture of several hundred different compounds. Synthetic essence, consisting basically of a solution of synthetic vanillin in ethanol, is derived from phenol and is of high purity.
Vanilla grows best under hot humid climate from sea level to an elevation of 1500 m. Most of its production is done 10 to 20 degrees above and below the equator. The ideal growing conditions are moderate rainfall 150-300 cm evenly distributed through 10 months of the year. The optimum temperatures for cultivation are 15-30°C (~60-90°F) during the day and 15-20°C (~60-70°F) during the night. Ideal humidity is around 80% and under normal greenhouse condition it can be achieved by an evaporated cooler. However, since greenhouse Vanilla is grown near the equator and under polymer (HDPE) netting (Shading of 50%) this humidity is achieved by the RH of environment.
Soils for vanilla cultivation should be loose with high organic matter content and loamy texture. They must be well drained and a slight slope helps in this condition. Soil pH has not been well documented but some researchers have indicated an optimum soil pH of around 5.3. Mulch is very important for proper growth of the vine and a considerable portion of mulch should be placed in the base of the vine. Fertilization varies with soil conditions but general recommendations are: 40 to 60g of N, 20 to 30g of P2O5 and 60 to 100g of K2O should be applied to each plant per year besides organic manures like vermicompost, oil cakes, poultry manure and wood ash. Foliar applications are also good for vanilla and a solution of 1% NPK (17:17:17) can be spray in the plant once a month. Vanilla likes a lot of organic matter; therefore 3 to 4 applications of mulch a year are adequate for the plant.
Dissemination of vanilla can be achieved either by stem cutting or by tissue culture. For stem cutting a progeny garden needs to be established. Recommendations for establishing this garden vary, but in general trenches of 60 cm in width and 45 cm in depth and 60 cm spacing for each plant is necessary. All plants need to grow under 50% shade as well as the rest of the crop. Mulching the trenches with coconut husk and micro irrigation provide ideal micro climate for vegetative growth. Cuttings between 60 and 120 cm should be selected for planting in the field or greenhouse. Cuttings below 60 cm need to be rooted and raised in a separate nursery before planting. Planting material should always come from unflowered portions of the vine. Wilting of the cuttings before planting provides better conditions for root initiation and establishment.
Before planting the cuttings, trees that will support the vine must be planted at least three months before sowing the cuttings. Pits of 30 x 30 x 30 cm are dug 30 cm away from the three and field with FYM (farm yard manure) (or Vermicompost), sand and top soil mixed well. An average of 2000 cuttings can be planted per hectare. One important consideration is that when planting the cuttings from the base 4 leaves should be pruned and the pruned basal point must be pressed into the soil in a way that the 4 nodes are in close contact with the soil and are placed at a depth of 15 to 20 cm. The top portion of the cutting is tied up to the tree using natural fibers like banana or hemp.
Several methods have been proposed for vanilla tissue culture, but all of them begin from axillary buds of the vanilla vine. In vitro multiplication has also been achieved through culture of callus masses, protocorns, root tips and stem nodes. Description of any of these processes can be obtained from the references listed before, but all of them are successful in generation of new vanilla plants that first need to be grown up to a height of at least 30 cm before they can be planted in the field or greenhouse.
In the tropics the ideal time for planting Vanilla is from September to November when the weather is neither too rainy or too dry; but this recommendation varies with growing conditions. Cuttings take 1 to 8 weeks to establish roots and show initial signs of growth from one of the leaf axils. A thick mulch of leaves should be provided immediately after planting as additional source of organic matter. From cuttings to produce flower and therefore pods it takes around three years. As with most orchids, the blossoms grow along stems branching from the main vine. The buds, growing along the 6 to 10 inch stems, bloom and mature in sequence, each at a different interval.
Flowering normally occurs every spring and without pollination the blossom wilts and falls, and no vanilla bean can grow. Each flower must be hand-pollinated within 12 hours of opening. The only insect capable of pollinating the blossom is the Melipona, a bee, native only to Mexico. All vanilla grown today is pollinated by hand. A small splinter of wood or a grass stem is used to lift the rostellum or moved the flap upward so that the overhanging anther can be pressed against the stigma and self pollinate the vine. Generally one flower per raceme opens per day and therefore the raceme may be in flowering for over 20 days. A healthy vine should produce about 50 to 100 beans per year; however growers are careful to pollinate only 5 to 6 flowers from the 20 on each raceme. The first 5 to 6 flowers that open per vine should be pollinated so that the beans are similar in age. These agronomic practices facilitate harvest and increases bean quality. It takes the fruits to develop 5 to 6 weeks but it takes around 9 months for the bean to mature. Over pollination will result in diseased and inferior bean quality. A vine remains productive between 12 to 14 years.
Most of the diseases come from the uncharacteristic growing conditions of vanilla. Therefore, conditions like excess water, insufficient drainage, heavy mulch, over-pollination and too much shade favor disease development. Vanilla is susceptible to many fungal and viral diseases. Fusarium sp, Sclerotium sp, Phytopthora sp and Collectrotricum sp cause rots of root, stem, leaf, bean and shoot apex. These diseases can be controlled by spraying Bordeaux mixture (1%), Bavistin (0.2%) and Copper oxy chloride (0.2%).
Biological control of the spread of such diseases can be managed by applying to the soil Trichoderma (0.5 kg per plant in the rhizosphere) and foliar application of Pseudomonads (0.2%). Mosaic, leaf curl and Cymbidium mosaic potex virus are the common viral diseases. These diseases are transmitted through the sap; consequently affected plants have to be destroyed. The insect pests of vanilla include beetles and weevils which attack the flower, caterpillars, snakes and slugs that damage the tender parts of shoot, flower buds and immature beans and grass hoppers that affect cutting shoot tips. If organic agriculture is practiced, insecticides are avoided and mechanical measures are adopted for pest management. Most of these practices are implemented under greenhouse cultivation since in the field such conditions are very difficult to achieve.
UN Food & Agriculture Organization
There are three main commercial preparations of natural vanilla:
Vanilla flavoring in food may be achieved by adding vanilla extract or by cooking vanilla pods in the liquid preparation. A stronger aroma may be attained if the pods are split in two, exposing more of the pod's surface area to the liquid. In this case, the pods' seeds are mixed into the preparation. Natural vanilla gives a brown or yellow color to preparations, depending on the concentration.
Good quality vanilla has a strong aromatic flavor, but food with small amounts of low quality vanilla or artificial vanilla-like flavorings are far more common, since true vanilla is much more expensive.
A major use of vanilla is in flavoring ice cream. The most common flavor of ice cream is vanilla, and thus most people consider it to be the "default" flavor. By analogy, the term "vanilla" is sometimes used as a synonym for "plain". Although vanilla is a prized flavoring agent on its own, it is also used to enhance the flavor of other substances, to which its own flavor is often complementary, such as chocolate, custard, caramel, coffee etc.
The food industry uses methyl and ethyl vanillin. Ethyl vanillin is more expensive, but has a stronger note. Cook's Illustrated ran several taste tests pitting vanilla against vanillin in baked goods and other applications, and to the consternation of the magazine editors, tasters could not differentiate the flavor of vanillin from vanilla; however, for the case of vanilla ice cream, natural vanilla won out.
In an in-vitro test vanilla was able to block quorum sensing in bacteria. This is medically interesting because in many bacteria quorum sensing signals function as a switch for virulence. The microbes only become virulent when the signals indicate that they have the numbers to resist the host immune system response.