How to brew beer with fatty ingredients

Not so long ago we were seeing and reading about butterbeer in Harry Potter; an idea that sounds delicious and has its origin in the Tudor court as a hot, spiced drink. However, the reality is that beer as we understand it today outside of fiction does not get along with butter or fat in general. The Muggle world is still not capable of dissolving lipids in cold beer.

At this point, the advanced beer hunter will already have realized that some modern beers theoretically contain fatty ingredients. We are living in the golden age of pastry stouts, “dessert” beers packed with chocolate and creamy adjuncts. In fact, there is a very specific niche within Anglo-Saxon and American craft beer culture dedicated to brewing milk stouts with added peanut butter, commercially known as “peanut butter stouts”. How do they do it?

The reality is less sweet than we’d like. Breweries usually use fat-free flavorings or the denatured ingredient from which the lipids have previously been removed. For example, peanut essence or peanut powder, as with some instant cocoa mixes, or vanilla essence.

So why can’t we add buttery, greasy adjuncts to beer? Because the same thing happens as when you pour oil into a glass of water. The fat floats on top of the beer and creates a film that prevents proper foam formation, and it also acts as a barrier that keeps our precious liquid from releasing its aromatic qualities. In other words, it keeps you from enjoying your beer under optimal conditions.

There is an additional risk: oxidation. If an oxidized beer is already unpleasant in itself, the flavor contributed by oxidized fat ends up turning any good intention into a “drain beer”. Think, for example, of the yellow fat on any ham—does that seem appealing to you?

Let’s be clear: the problem with lipids is not exclusive to pastry-style beers. It is also a recurring issue when adding certain spices and fruits, since most seeds contain a more or less significant percentage of oil. What’s the solution in the case of fruits and vegetables? It’s actually quite simple. Just remove the seeds and add the pulp.

That said, it’s best to always check the fat percentages in any adjuncts you want to add to your brews. In any case, you can relax: beer doesn’t contain cholesterol!