Cleanliness -Is- Close To Godliness

[by Mike]

I've mentioned fat washing in an earlier post, and while the concept has always intrigued me I had never attempted the technique until over the break. That's a shame, really, because fat washing is perhaps the latest trend most cooperative to the home mixologist; the application is straightforward, fast, and by its very nature cheap.

For the unfamiliar, fat washing is all about hacking booze. When sugars are initially fermented into alcohol, the byproducts are not just ethanol and carbon dioxide. All kinds of molecules can be created, some which give an individual spirit its unique character and others that can contribute off flavors or be outright dangerous. Distillation is all about extracting as much of the desired ethanol and flavor compounds as possible while avoiding those less agreeable to the palette (or health, depending on your priorities).

Careful distillation produces a finer, smoother product at the expense of yield; aging further reduces undesirable compounds at the expense of time. Because both approaches cost money, the end result is that quality spirits tend to correlate with lighter wallets.

Is there any use for the cheaper bottles, then, besides fueling college misadventures? Like so many things in life, the answer can be found in fat. You see, some of those unappealing flavor compounds are highly fat soluble. Once fat has dissolved in alcohol it will start binding with the molecules, particularly those responsible for the astringent vapors so characteristic of bad booze. Removing the fat then leaves a much smoother spirit at a fraction of the cost.

Almost any fat can be used, but easy removal necessitates animal fats that will solidify in the refrigerator and can be simply strained out of the alcohol with a fine mesh. Because fat dissolves so well in alcohol, trace amounts will be left behind no matter how well the alcohol is strained. While flavor neutral fats such as lard can be used to avoid introducing any new flavors, the real magic of fat washing happens when particular fats are used to impart complementary flavors to the spirit at hand.

The most famous applications so far have been with whiskey, utilizing both bacon fat and butter to round out younger bourbons and ryes while adding a rich note rare to most spirits. When considering my own application, however, I reached for unaged tequila with grassy and vegetal flavors complementary to more savory fats. My fat of choice would be freshly rendered duck fat.

Again, the process could not have been more simple. After picking up an inexpensive bottle of Sauza blanco, I added melted duck fat (75 parts base spirit to 4 parts fat) and let the solution sit overnight. The next day I threw the bottle into the fridge and by the evening I was sipping a smooth, velvety spirit laced with the luxurious taste of duck.

An improvement over shots, no?