Authors: nytimes Diners Journal
Diner’s Journal has asked Garrett Oliver, the brewmaster at Brooklyn Brewery, to make a batch of White House Honey Ale — President Obama’s home brew — for us to sample and size up. Mr. Oliver started on Sept. 14, and is filing reports on its progress:
As we left our White House Honey Ale in my last post, I had added the yeast to the wort (unfermented beer) and put the fermenting jar in the barrel aging room here at Brooklyn Brewery. We use this room to age beer in bourbon barrels at gently chilled temperatures. Within a matter of hours, the yeast started to consume the malt and honey sugars, creating carbon dioxide, alcohol and various flavors.
A close look through the side of the glass jar reveals the usually hidden world of fermentation, and a very active world it is. Murky with yeast, protein and hop particles, the fermenting wort churns and swirls, kicking up a head of foam at the top of the bottle. Most ales ferment best at 68 to 72 degrees, while lager beers have cold fermentations. This is one reason that most home brewers try to do most of their brewing in the cooler months: higher fermentation temperatures tend to create rough flavors.
Fermentations are exothermic, which means that they give off their own heat, and that heat needs to be kept in check. Centuries ago, many parts of Europe had laws that forbade brewing in summer, because the resulting beer was often bad. A look at the video White House officials released reveals that their “beer room” has air vents and a temperature of 66 degrees, so they’re clearly in good shape. We also adjusted our thermostat to 66.
By the fourth day, the foam on the surface had dissipated, the currents inside the jar had stilled and the yeast had started to settle out of the liquid. As the yeast settled, the beer appeared to become darker and clearer from the top down. By the seventh day, all visible activity had ceased, and the fermenting wort had become beer.
The White House recipe calls for transferring the beer to a secondary fermenting vessel, to remove it from the settled yeast. Once the fermentation is finished, some of the yeast will start to die, giving off flavors that vary from toasty to meaty. While these savory flavors are often revered in Champagne as “sur lie” (on sediment) character, they’re not considered desirable in fresh beer.
At this point in the video, there is something the White House brewers don’t mention in the recipe: once they’ve transferred the beer to the new jars, they seem to top them off with water. I’m assuming that the goal is to protect the beer from the air that would otherwise be in the head space of the jar. Oxygen is one of beer’s greatest enemies, and it quickly degrades fresh flavors. However, adding water will also dilute the beer.
Last Thursday, to get a clearer picture of my batch, I used a large pipette called a “thief” to remove about a quarter-cup of beer from the jar and take it to our lab. I and my lab manager, Tom Price, injected the beer into our “beer analyzer” (yes, such a device does exist), and a few minutes later, out popped a little ticker tape that looked just like a receipt. It revealed an “original gravity” of 13.2 degrees on the Plato scale, which means that our original wort was 13.2 percent sugar by weight. The finishing gravity was 4.1 degrees (because the yeast consumed the rest of the sugar), and the alcohol by volume was 4.89 percent. The more sugar the yeast consumes, the stronger the beer will be.
I had thought the beer would be slightly drier and stronger than it turned out to be. But there were two unknown variables here: the pre-made malt extract and the yeast strain I used, both of them for the first time. Not all malt sugars can be fermented, and some yeast strains are more aggressive than others.
A quick taste of our proto-beer revealed a broadly fruity palate with some caramel and floral notes, and a good balancing bitterness. Based on this and the lab analysis, I decided to follow the recipe as written and leave the beer undiluted. We will bottle soon, and I think this beer is going to be fine.