The Art of Blending Beer

These are the normal steps of producing beer commercially: mash and boil, ferment, age, package. For brewers creating barrel-aged beers, particularly those who use multiple or wild yeast strains, the process is a lot more involved. The process begins the same way, until a brewery has a "base beer." Instead of proceeding to packaging, however, the brewer transfers the beer into wooden casks, offers a prayer to a higher power, and waits. In those barrels, nature happens. A lactobacillus culture down the road (and maybe a rogue brettanomyces or two) and the goes through strange and wondrous transformations. Eventually, a brewer will begin to sample the beer in these different barrels to assess their nature and characteristics. Finally, he settles on a blend that will produce the ultimate flavor he wants.

Yesterday afternoon, Ron Gansberg invited me to join him in this process. Knowing that I love his apricot ale, we spent the afternoon sampling beer from different barrels, assessing, and ultimately putting together a rough blend that would approximate the final beer. Fascinating stuff.

We started out by trying beer that had been aging with the fruit. There are three batches of this beer, with two varieties of apricots. The base beer that Ron uses for this blend is roughly a strong golden/trippel. It's based on his Tempter Trippel recipe, but with fewer hops. These beers were very sweet and saturated with fruit essence--I was reminded a bit of the heavy syrup you find in tins of canned fruit.

Then Ron started rummaging through the dozens of barrels he has in the brewery, looking for ones he and his assistant Curtis had identified as possible matches for the apricot. What they're looking for are qualities akin to the fruit--light, high notes, delicate sweetness, and some sharper sourness to balance the sugar. He had split one batch of the trippel into several barrels, and we tried these in turn. Although I have understood intellectually that barrel-aging changes beer, it was fascinating to see how the same base beer changed depending on what had happened in each barrel. One was cleanly lactic, lighter and more sharp; another was heavier, sweeter, with a sour bending toward the acetic. Even their colors weren't the same--the sweeter one had darkened some.

In his way, Ron was pulling plugs on various beers as inspiration took him. One barrel produced a deeper, mustier sour. Teri Fahrendorf had stopped by the brewery and joined us at this point, and she speculated that it might be some brettanomyces. It's an older barrel, so a latent colony might have started to express itself. (That won't go into the apricot, but it will find itself into something. Ron will put it in the back of his mind, and when he wants a bit of funk in something down the line, he has a cask to turn to.) One very promising barrel contains a spiced golden beer. It was very sweet, but light and a bit citric--when added to the apricot-aged beers, it made the fruit pop while lightening and brightening the beer itself. That was the kind of alchemy he was shooting for.

Finally, he began doing calculations based on all the batches we had tried. ("Let's see, half a milleliter per gallon is 100 plus half a milleliter multiplied by the three barrels is 300, plus ..." I nodded sagely.) We took it back to the brewery and tried the first cut. Actually, it wasn't quite right. Too much non-fruit blends. Ron will have to go back to the drawing board and rejigger the ratios. So it goes with blending beer--you have to get the proportions just right.

Our plan is to follow an apricot ale through from brew to bottle, and this was the first step (though it was actually toward the end of the process). I shot some video, and I hope to compile it together to show how involved the whole process is. I may cut together something rough from this segment--or not. Stay tuned, though, this is fun stuff.