VANILLIN
what is vanillin?
Synthetic Ingredient For Perfumery Overview
Vanillin is a phenolic aldehyde, which is an organic compound with the molecular formula C8H8O3.
Its functional groups include aldehyde, hydroxyl, and ether. It is the primary component of the extract of the vanilla bean. Synthetic vanillin is now used more often than natural vanilla extract as a flavoring agent in foods, beverages, and pharmaceuticals.
Vanillin and ethylvanillin are used by the food industry; ethylvanillin is more expensive but has a stronger note. It differs from vanillin by having an ethoxy group (–O–CH2CH3) instead of a methoxy group (–O–CH3).
It appears as white or creamy-white needle-like crystals and sublimes when heated.
Natural "vanilla extract" is a mixture of several hundred different compounds in addition to vanillin. Artificial vanilla flavoring is often a solution of pure vanillin, usually of synthetic origin. Because of the scarcity and expense of natural vanilla extract, synthetic preparation of its predominant component has long been of interest. The first commercial synthesis of vanillin began with the more readily available natural compound eugenol (4-allyl-2-methoxyphenol). Today, artificial vanillin is made either from guaiacol or lignin.
Lignin-based artificial vanilla flavoring is alleged to have a richer flavor profile than oil-based flavoring; the difference is due to the presence of acetovanillone, a minor component in the lignin-derived product that is not found in vanillin synthesized from guaiacol.
The use of the word “Vanilla” is more or less forced, and not very descriptive since today so many people are living without ever seeing or smelling a Vanilla bean (pod). The “Vanilla” in their mind, is actually derived from a Vanillin-flavored product (Chocolate, ice-cream, etc.) and it is not surprising that the Vanillin smells of vanillin.
A typical example of the human deficiency in odor description: smelling highly diluted Vanillin is “Chocolate”, often the first reaction to the odor of Vanillin.
However, the “creamy” effect of Vanillin in trace amounts in perfumes is rather typical.
Higher proportions often cause sickening sweetness and very conspicuous notes in the dry down (terminal odor).
Profile
📂 CAS N° 121-33-5
⚖️ MW — 152.15 g/mol
📝 Odor Type — Gourmands
👃🏼 Odor Profile — Sweet, sugary, powdery, burned (phenolic), almonds, spicy. Intensely sweet and very tenacious creamy Vanilla-like odor.
👅 Flavor Profile — The taste is generally sweet, but it depends greatly upon the base. Vanillin for flavor purposes is often evaluated in ice-cold milk, sweetened with about 12% sugar. Concentration of 50ppm in this medium is clearly perceptible and will not fatigue the evaluator.
⚗️ Uses — As a companion to the conventional “crystals” in ordinary perfume formulations, Vanillin is very widely used, It is practically always the smaller (amount) of crystalline materials, but the frequency of its use, combined with its enormous use in flavors, making it one of the largest volume, crystalline aroma-chemicals. Its intense sweetness is utilized in industrial masking odors and in high-cost luxury perfumes, and it can be used in almost any type of fragrance, from woody or herbaceous to Oriental or floral.
As a result of the volume of Vanillin produced, considerable research has been spent on perfecting the material, and it is one of the purest perfume and flavor chemicals – from a chemical point of view. While Vanillin has been improved, so has many raw materials for the functional products. And this may be part of the reason why Vanillin is no longer the considerable “hazard” in a soap perfume as it was ten or twenty years ago. The soap has been vastly improved, and so has Vanillin. It does not discolor a soap today to the degree it would have done in soap 20 years ago. this should not be translated so that Vanillin is not an “offender” in a soap perfume. It still is, but just not a very serious one.
As a masking agent for numerous types of ill-smelling, mass-produced industrial products, particularly those of synthetic rubber, plastic or fiberglass, etc., Vanillin finds very extensive use. It is often the most inexpensive material for the amount of masking effect it gives. Crude Vanillin is acceptable for such purposes.
In flavor compositions, Vanillin is used widely as a sweetener, not only in Vanilla imitation flavor but in Butter, Chocolate, all types of fruit and tutti-frutti flavors, root- beer, “Cream-soda” etc. It is acceptable at widely different levels of concentration, and while 50 to 1000 ppm is quite normal levels in the above types of product (finished products) concentration up to 20,000 ppm (one part in fifty parts of finished goods) are also used for direct consumption (toppings, icings, etc.). Ice-cream and Chocolate are among the largest outlets for Vanillin in the food and candy industries, and their consumption is many times larger than that of the perfume industry.
Problems
Vanillin will often produce off-color with Anthranilates, indoles, quinolines. with traces of Iron (e.g. from crude essential oils or Resinoids).
Due to its phenolic nature, vanillin tends to get colored if exposed to light. This happens especially when in dilution
However, normal use levels of the material cause very little trouble in perfumes or functional products. Certain perfume types may have exceptionally high proportions of Vanillin (5 to 8 10) and such perfumes can rarely be used in white functional products (creams, hand lotions, etc.), but they may be acceptable in pink or cream-colored products, where a the Vanillin would slight discoloration from not be visible.
Production
There is something close to 100 patents about vanillin production. Here are the most used \ important.
from Lignin.
In principle, it is the very first method commercially used. It is based upon the utilization of the glucoside Coniferin, which can be hydrolyzed to yield Coniferyl alcohol. This alcohol can be oxidized to yield Vanillin (and Acetaldehyde). Coniferin is also known as Abietin. Naturally, occurring Lignin is enzymatically decomposed to give various products, one of which is Coniferyl alcohol.
from Guaiacol.
This is the only truly synthetic method of importance, All other methods are based upon a natural starting material, closely related to vanillin in chemical structure.
The reaction includes chloroform and alkali (old method) or Chloral (= Trichloro acetaldehyde), followed by oxidation of the resulting chlorinated carbinol, and hydrolysis to yield Vanillin,
from Eugenol.
The method usually goes via iso-Eugenol, Acetyl iso-eugenol. which is Oxidation and hydrolysis yield Vanillin.
from Safrole.
The method has great importance where Safrole-bearing ‘essential oils are abundant and inexpensive (Japan). The process goes via iso-Safrole and iso-Eugenol to Vanillin. This process, too, may yield some iso-Vanillin, since iso-Chavibetol is formed parallel to the iso-Eugenol in the process.
Method No.1 is by far the most important today. A certain amount of Vanillin ex Eugenol is specifically requested by the flavor industry, or by flavor houses insisting upon a “very natural Vanillin”. The production of Vanillin from Lignin has come to such perfection that a cream-colored product (from Lignin) can sell as “Vanillin ex Eugenol”. The industry expects the latter type to be off-white or cream-colored, while Lignin-Vanillin is practically snow-white.
It is possible to smell a difference in the vanillins of different origins, but it is normally very difficult to taste a difference, provided the various samples are otherwise good quality. Adherent or absorbed odor upon the crystals will perceptibly affect the odor of vanillin out of a fiber drum or some other large container and the material il very sensitive to contamination with other crystalline odor chemicals.
An admixture of 0,05% of coumarin to vanillin will introduce an entirely different odor. Yet vanillin is considered a more powerful odorant than coumarin.
Notes
Should never be stored in contact with iron.
Should not be used in compositions where a reddish color - which can appear with time, is a negative point.
1% soluble in water.
5% soluble in Glycerin, soluble in Propylene glycol, alcohol, and oils.
Vanillin is easier soluble in diluted alcohol than in concentrated alcohol. A similar situation is observed with Glycols.
Among the more common perfume materials, Vanillin is one of the most tenacious odors known.
Sources:
Informations are sourced from Perfume and Flavor Chemicals - S Arctander,
Aromatizzazione - Fenaroli.
National Center for Biotechnology Information (2020). PubChem Compound Summary for CID 1183, Vanillin. Retrieved November 25, 2020 from https://pubchem.ncbi.nlm.nih.gov/compound/Vanillin.