Surviving the Daily Grind

BYOB by | Jan 2011 | Issue #48

Illustration by Ellen Crenshaw

Back during my “live brew” column (issue #45) about the Mortgage Killer brew, a faulty grain mill cut short my first attempt. I started thinking about that one piece of gear and the way it can grind the brew day to a halt.

Excusing the pun though, the importance of the crush cannot be understated, and neither should you underestimate the way it can completely derail a brew.

Barley, like other cereal grains, contains seeds that consist of a protective shell wrapping the starchy food source. Left to its own devices and given a little moisture, the embryonic planting will break down the starch and use the resulting fuel to generate roots, shoots and leaves. For our purposes, maltsters carefully control the initial growth to free the starch and degrade the protein, but they still leave the grain intact for protection and storage. So we have to crush it to get at the goodness we desire.

Of course, nothing is ever simple, so we have conflicting needs from our crush. If we pulverize the endosperm into flour, we now can hydrolyze every bit of starch. The malt enzymes can chew every last starch and spit out a mass of sugar. Great! You are now maximally efficient and can use less grain. One problem arises, because instead of a loose barley soup, we’ve made slow-draining dough. Doesn’t matter if you’ve got all the time in the world (incidentally, this is how to determine a malt’s sugar content). But when labor and time cost money, you’ve got to get things flowing. For that, we need that pesky protective shell, the hull. Since it doesn’t dissolve or get gummy, it can sit between pockets of wet starch and weave channels for water to flow and wick away sugar. The more intact the husk, the better it works. Mills that produce flour tend to shred the husk, reducing its efficacy—hence the crushing conundrum.

In the early days, we had to resort to rolling pins, blenders, food processors and the dreaded Corona mill to crush the small amount of malt we used. Since extract brewing doesn’t rely on the husk’s filtering power, the malt flour typically produced by these somewhat tedious means (or the KitchenAid milling attachment) was acceptable. But for mashing brewers, unless it’s done with supreme care, the shredded husks make the malt unusable.

Great strides in the past decade have sidelined these options. For a small price, every homebrewer can have their own mill patterned on the gizmos used by our professional counterparts. Every model out there has its adherents and rave reviews. Look for a model that you can easily power with a drill or motor—unless you like the Popeye-forearm look that’s sure to result from hand cranking a batch worth of malt. A two-roller mill, with an active driven roller and a passive roller, produces an awesome crush with a minimum of shredded husks. Many are adjustable; while not necessary, adjusting the fineness of the crush can produce dramatic changes in efficiency.

Just how fine can you go with your crush? The internet’s general rule of thumb says, “Crush until you’re scared and then crush a little more.” A finer crush (via less space between the rollers) can yield greater amounts of gravity, but if you go too far, you’re in the dough-ball scenario. The wise and brave brewer keeps rice hulls—a flavorless source of additional filtering material—on hand while shooting for the moon. True brewernauts should look online for BrauKaiser.com’s experiments with malt conditioning to produce perfect husks.

In reality, you don’t have to shoot for the maximum efficiency from your crush. Most mills’ default settings work like a charm. Even then, it’s a great idea to have your own mill to take advantage of bulk pricing and never have to worry if someone messed up your local homebrew shop’s mill.