Vanilla

#### Vanilla. One of the most intriguing and inimitable flavor and perfume materials is **Vanilla**. The story of vanilla is a tale in itself, and the process of curing the immature green capsules into the deliciously fragrant chocolate-brown vanilla “beans” is no less fantastic. Literature is abundant on the subject of cultivating, curing and extracting vanilla, but a few brief details should be mentioned a this place. To the author’s opinion, literature on vanilla extraction leaves much to be desired yet. The vanilla plant is an orchid, a climbing vine that needs a supporting tree or trunk into which the vine sends tiny, but strong “hooks”, often mistaken for suction roots. But the plant is not a parasite. It takes all its nourishment from the soil and the air directly. The plant **Vanilla**** ****Planifolia **is a native of Central America or Mexico where a local insect with a particularly long trunk takes care of a natural pollination of the flower. When Fernando Cortez brought the plant to Europe shortly after the discovery of America, it remained for a long time a mystery that the plant did not produce fruits outside its native country. More than 300 years later, a method of hand-pollination of the flowers of vanilla plants in the island of La Réunion in the Indian Ocean resulted in the plants producing fruits. From then on, methods of curing were developed, based upon experience from the natives in Central America, and before the end of the 19th century, cured vanilla “beans” were among the most appreciated flavoring materials. About that time, synthetic vanillin sold for U.S. $ 1100.— per kilo. “Natural” vanillin could hardly be produced from vanilla fruits today at that price. Synthetic vanillin from lignin (a wood pulp derivative) is today available at less than one percent of the above price. The vanilla plant is cultivated for the production of fruits in Mexico (one of the native areas of the plant), in Madagascar, La Réunion, Tahiti, the Comoro islands, Guadeloupe, East Africa, Indonesia, the Seychelles, etc. Madagascar is the largest producer by far (up to 80% of the total world production), followed by Mexico (different curing process yields a different quality), La Réunion (same process as Madagascar, and considered the best quality vanilla), Comoro islands (rapidly growing industry), and Tahiti (considerable production, but the plant is a different hybrid and yields a distinctly different vanilla aroma). Other producers turn out a few tons or less of cured fruits annually. The vanilla flowers are hand pollinated (even in Mexico where the growers cannot expect the local insects to do a 100% effective job), and the flower produces a fruit which reaches maturity after 8 to 9 months on the plant. Immediately prior to maturity, the fruit is harvested, and the green, odorless, bitter tasting and somewhat poisonous “pods” now face a long and troublesome curing period, not unlike the curing of tea and tobacco. The curing leads to enzymatic processes within the fruits which slowly turn brown and become aromatic. The curing of vanilla fruits is performed locally, except in the Andapa (inland jungle) district of Madagascar where no experienced curers are at hand, although many hundreds of tons of green pods are harvested there. The fruits are air shipped to the coastal district for proper curing. After three months or more curing time, the “pods” (botanically the fruit is a capsule) are ready for shipment. Before being shipped, they are sorted according to length and appearance. The trend is towards a drier export material. The greatest bulk of all vanilla ends up in extraction units in Europe and the U.S.A. The old-fashioned, glossy, soft and attractive fruits with their very high moisture content (occasionally up to 70%, but usually 30 to 50 % water), cause considerable trouble in the extractors, diluting the solvent, giving a poor yield, etc. Today, a rather unattractive, unsorted (with respect to appearance), but selected aromatic quality of low moisture content is preferred by the large consumers. After tedious experiments in Madagascar, “chopped” fruits, dried under infra-red lamps are also available now. The drier the fruit, the faster will the vanillin crystals appear on the outside of the fruit. It may take a year or more on whole, moist fruits. It is, however, no sign of high quality, since this “frosting” can be attained by sprinkling the vanilla fruits with an ethereal solution of synthetic vanillin (compare **Tonka Bean**). From Madagascar and La Réunion comes the so-called **Bourbon**** ****Vanilla**, named after the island of Bourbon (La Réunion) where the curing method was developed. Mexican vanilla is also derived from **Vanilla Planifolia **(a hybrid of other vanilla plants), but the Mexican curing method is slightly different from the Réunion curing. The Mexican vanilla is somewhat sharper or more pungent in its aroma. **Réunion**** **or **Bourbon Vanilla**** **appears as chocolate-brown, semi-dry or somewhat moist, dull or glossy. 14 to 22 cm. long “sticks”, which may be bundled in different ways according to origin, or may be sold “en vrac” (i.e. loose in box). The aroma is extremely rich, sweet, somewhat woody and animal (castoreum-like), tobacco-like and very deep in its balsamic, sweet-spicy body- note. Actually, the odor of vanillin is *not *one of the characteristics in the aroma of Bourbon vanilla. However, the odor varies considerably according to the moisture content of the fruits; thus, the odor of very moist fruits is usually more to the vanillin side. The drier the fruits become, the more perceptible is the odor of the non-steam- volatile, high-boiling aromatic principles. **Tahiti**** ****Vanilla**** **is generally shorter in length and mostly a bundled, moist fruit. Its odor is almost perfumery-sweet, not tobacco-like, not very deep or woody, nor distinctly animal. Some people find it more attractive, perhaps because it reminds them more of the everyday (artificial) vanilla flavors in ice-cream, candies and baked goods. A certain type of **Guadeloupe Vanilla **is called “Vanillons” and the fruits are derived from **Vanilla**** ****Pompona**, a different species of vanilla. The fruits are short (8 to 14 cms.) and wide (up to 2 ½ cm. flat measure). They have a peculiar floral-sweet fragrance of the anisic, heliotropineisosafrol type, and are more perfumery than all other vanilla types. Vanillons are considered poor quality vanilla for flavoring purposes. The cured vanilla fruits do not yield any appreciable amount of essential oil by distillation. Even the molecular distillates of vanilla extracts do not represent the rich and typical gamut of vanilla flavor. No “aroma distillate” (see this monograph in Part One of the present work) can be made from vanilla fruits. The following perfume and flavor materials are manufactured from cured vanilla fruits: **Vanilla Absolute, Vanilla Extracts **(with various solvents and in various concentrations), **Vanilla “Resinoid” **(also called “oleoresin”), **Vanilla Tincture **and several other types of aroma concentrates. The following monographs will describe the most common products of vanilla fruits. ##### Vanilla Absolute. The highest concentration of vanilla aroma (perfume and flavor) is found in the so-called **Vanilla Absolute**. It must be mentioned at this point, however, that this absolute is not representative of the total aroma of the vanilla fruit. Certain aromatic materials, particularly flavor ingredients, are lost in the attempt to produce an alcohol- soluble extract of this botanical. The conventional way of washing the hydrocarbon solvent extract (in this case: the “**Oleoresin of Vanilla**”) with alcohol does not yield a satisfactory result. If the vanilla fruits are extracted with hot alcohol (e.g. infusion), and the resulting extract is evaporated, we will find that the extract is not soluble in ethyl alcohol. Even if the infusion is set aside for several weeks and filtered before the alcohol is removed, it will not be alcohol soluble. Hydrolysis and other processes continue to work in the extract. Certain resinous substances will remain in clear solution for a considerable length of time before they finally “fall out” as a gummy precipitate in the extract. The so-called selective extraction method has recently been applied to vanilla fruits with good results. It is important that the moisture content is very low in the starting material (see the general remarks under the monograph Vanilla). It is possible to eliminate the alcohol-soluble resinous matter, etc. and obtain a truly alcohol-soluble absolute of vanilla. Other manufacturers have tried to reach this goal by use of co-solvents, a method which is less than perfect and not universally useful. This absolute is about 7 to 13 times stronger in flavor effect than vanilla fruits of average moisture content, while the alcoholic extract prepared with diluted alcohol is only 3 ½ to 5 times stronger than vanilla fruits (see monograph on **Vanilla Extract**). **Vanilla Absolute **is a dark brown, clear and viscous liquid of very rich, sweet and true-to- nature odor. An odor-flavor description of this product would not be correct without the remark that the flavor is strongly dependent upon the type of vanilla used in the extraction. **Vanilla**** ****Absolute**** **from **Vanilla**** ****“Oleoresin”**** **is commercially available, usually prepared from the benzene extract of vanilla. In that case, it should be used for perfumes only (even traces of benzene are harmful to the human organism). The absolute is very dark brown and semi-solid, just about pourable at room temperature. It is less rich in odor than the direct alcohol- (or hydro-alcoholic) extraction products, and the perfumery effect is not proportional to its concentration over the vanilla tinctures.