Chemical Explanation: Vanillin, the Weirdest Little Semi-Natural in Fragrance

What is vanillin? How’s it made? Is it dangerous? Why does it turn soap brown? Barrister and Mann is here to explain!

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We get lots of questions about the fragrance materials we use. People often send me emails asking whether some of our high-vanillin products have separated, so I wanted to cover some background about vanillin to dispel any concerns.

Vanillin is found in TONS of foods, essential oils, synthetic fragrances, and sometimes even medications. It’s a colorless, crystalline powder that smells very strongly of vanilla (with a touch of cotton candy). Unadulterated vanillin is not the rich, dark vanilla scent of vanilla absolute, but instead the sweet, airy vanilla of carnival candy during the summer time.

The atomic structure of vanillin.
Behold the mighty vanillin, browner of soaps and maker of ice creams and marshmallows.
How is it made?

Chemical companies refine vanillin from a molecule called lignin, which they produce from the waste left over from the cellulose (paper) industry. Tasty, right?

Manufacturing teams treat the concentrated waste material, called “mother liquor,” with various alkaline substances (usually lye), and heat it under pressure. The teams then separate out the vanillin through various extraction and distillation processes. Especially cool, the technical methods for manufacturing vanillin have become so precise over the course of the last century that it is nearly impossible, through lab analysis or otherwise, to determine whether the source is natural or synthetic. It’s really that pure.

Is it the same as vanilla absolute/essential oil?

Not even close. Commercial vanillin, as discussed above, is made in a laboratory, but otherwise nature-identical. In contrast, low-boiling solvents like hexylene are used to make vanilla absolute, vanillin’s inedible-and-prohibitively-expensive natural cousin. Distillers soak vanilla beans in hexylene, which they later boil off, leaving behind “concrete” (CON-kreht). They then wash the concrete with alcohol and centrifuge it to separate out the resins and other solids. Those solids are what makes natural vanilla smell dark and rich and wonderful. Thankfully, there’s no hexylene left over at the end, though.

This washed centrifugation product is the absolute, which sells for roughly $150/ounce on the open market. That makes it way too expensive for most commercial purposes.

I’ve heard that vanillin can discolor soap and other toiletries. Is that true?

Vanillin is classified as a non-sensitizing and non-irritating compound, but it’s usually off-limits for commercial soap manufacture. Even small quantities can discolor the product (and the more you use, the darker the color). Tragically, all attempts to employ vanillin derivatives as replacements have been unsuccessful. They either discolor the product like the real thing, or they simply don’t smell like vanilla. Johnson and Johnson actually spent two years and about $8 million trying to fix the problem. They eventually gave up. Nobody puts vanillin in the corner.

Because the various bonded groups of a vanillin molecule react easily, exposure to air causes it to slowly oxidize into vanillic acid. Vanillic acid, in turn, is what discolors soap and other products. Though otherwise harmless, vanillic acid in shaving soaps can occasionally discolor heavily bleached animal hair shaving brushes, especially white badger. The discoloration is generally not permanent, but can be a bit shocking. However, you can easily remove it by soaking your shaving brush in a mild vinegar/water bath (3 parts warm water to 1 part vinegar), cleaning it with soap, and allowing it to dry naturally.

Why does Barrister and Mann even use vanillin, then?

The answer’s pretty simple: there aren’t really any good replacements that are soap-stable, and we feel that it’s important to our brand to continue to push the fragrance envelope. Because vanilla is not a common scent in shaving otherwise, we’re willing to deal with the problem (unless we can find some other way to do it, which is not especially likely) in order to continue to advance and refine our work.

That said, we don’t make many soaps that use high levels of vanillin. To date, only Lavanille and Night Music have used enough to become seriously dark, and only Lavanille remains in constant production.

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For artisanal shaving soaps, visit Barrister and Mann. For the best smelling and feeling aftershave you’ve ever put on your face, check out Barrister’s Reserve.

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