Vanilla extract with pure alcohol

Question

Nearly every recipe for making vanilla extract suggests the use of Vodka, or an alternative alcoholic beverage with a high alcohol content (typically 35%+), such as Rum or Bourbon. However, the various recipes typically default to Vodka for its more neutral taste. Essentially, the recipes simply instruct to leave opened vanilla pods in the alcoholic beverage for at least several months. The high alcohol percentage is required for the vanilla flavour to diffuse over time.

This made me wonder why I cannot find a single recipe that simply recommends the use of pure food grade ethanol, like that used to make Limoncello or other fruit- or herb-based liquors. It is typically cheaper, does not add additional flavour, and its high alcohol percentage (typically 95%+) (Rectified spirit) should suggest a better diffusion of flavours, or not? What am I missing?

Answer 1

I can see two possibilities.

One is that vodka and the like are highly available. You can buy them in almost any country, and in most places just in a supermarket. They're even fairly likely to be on the shelf at home - I made vanilla extract using rum that I'd had for ages, when the covid home-baking boom meant vanilla extract sold out in my local supermarkets.

Pure high-proof alcohol is only cheaper if you're going to use it all in flambéeing, making extracts, etc. - you're not going to drink up the leftovers. At least here in the UK, spirits are taxed by the amount of ethanol you're buying. So a bottle of 80% ABV would attract twice as much tax as a the same size bottle of 40%. That means the pure stuff is going to look very expensive, which will go some way towards explaining its limited availability - and specialist retailers aren't cheap.

But there's reason another too. We use true vanilla extract because it's a more complex flavour than its main component vanillin. Vanillin is far more soluble in alcohol than in water, but the other compounds that contribute to a natural vanilla flavour may not all be. In that case you'd actually want a decent amount of water to extract these other compounds.

After all, even industrially, when pure ethanol is a readily-available ingredient, a water-ethanol mix is used for the extraction (see, for example, this patent), rather than extracting into ethanol and then diluting for sale.