HBK #4, Day One, Part Two: Mash, Lauter, Sparge

So, when we left off, we had a big bag full of ground barley freshly milled at Portland's lovely U-Brew Home Brew Supply Store.  We'll skip the part where the three of us stood in line, paid for the grain, and drove out to get a beer and pizza, and instead move straight to the mashing process.

Our ultimate goal with mashing is to turn malt into wort.  Or, rather, we aim to take all of the starch and flavor out of the grain, but leave the fibrous solid matter behind.  We do this by soaking the malt in hot water at a constant temperature for about an hour, then filtering out the rich, sugary deliciousness known as wort in a process called lautering.

The whole thing starts with a well-insulated container, called a mash tun.  It looks a lot like the Gatorade cooler that gets dumped over a football coach's head after a championship win...the key difference, though (besides the fact that dumping these scalding hot contents onto a person would be tantamount to attempted murder), is that a mash tun has a false bottom - essentially a grate - which keeps the milled grain in the tun but allows the wort to run out of a nozzle at the bottom.  During this process, tiny particles of grain are filtered out...though not by the grate itself, but instead by the tightly packed larger chunks that collect in the grate's mesh.  But I'm getting ahead of myself...

Water which has been heated to about 180°F is poured into the mash tun until it's about half-way full (this, as far as I could tell, was a matter of eyeballing the space needed to fit all 12 pounds of grain in addition to the hot water).  Here, the insulation of the tun will keep the water at a relatively constant temperature for the hour or so of the mashing process...but 180°F is far warmer than we want our grain for the mashing to be successful; in order to get the ideal breakdown of starch-into-sugar (you were paying attention during the last blog post, right?), we want our grain to be right around 150°F (or, according to several homebrewing websites, between 144°F and 163°F).  So why make the water so hot in the beginning?  It's because we've got 12 pounds of room-temperature grain that are about to be mixed into it, which will cool it down significantly.  Tim's goal (and he had extra hot water on hand in order to make sure he could meet it) was to mash in the upper 140s, and we ended up doing just that:  the grain was added, the temperature was adjusted with some extra water, and the whole thing was stirred like crazy with the largest spoon I can recall having ever seen in someone's silverware drawer, resulting in a 147°F mash for one hour.

Now, the smell of a bunch of grain being mixed with water is neither the most pleasant nor the most unpleasant scent in the world...in fact, it's pretty inoffensive; it smells pretty much like a farm, minus the manure and diesel.  But the delicious aroma of grain that's been mashed for an hour is one of the more incredible things I've ever taken in:  imagine a dark, rich beer, except with no alcohol, tons of sugar, and hot.  (Okay, reading that back to myself, it sounds gross, so I'm going to have to ask you to just take my word for it:  it's amazing.)  What we have now is a wort, mixed with a bunch of almost totally spent grain, just waiting to be filtered out.  However, we only have about four gallons of water in there, and a lot of that has been sucked up into the grain...but we have a six-gallon container to fill full of wort.  WHERE DID WE GO WRONG?!

Before we get all bent out of shape, I should mention another new vocabulary word...my favorite that I learned in this initial foray into brewing, in fact: "sparge."  Sparging is the process of running water through the grain after the mash, trying to extract the last of the sugars while simultaneously heating the grain enough so that the starch-to-sugar conversion stops...yet not hot enough that we leech tannins out of the grain (as this would add unwanted bitterness to the final product's flavor).  So, water is heated (again, to about 180° or preferably a little under), the filter at the bottom of the mash tun is opened, and the wort is allowed to slowly trickle through a tube from the tun into a boiling kettle below (again, this part is called lautering).  The water needs to be added slowly so as not to disturb the grain's self-made "filtering system" in the bottom half of the tun, and this was accomplished (with, in my opinion, only partial success) by pouring it through a metal sieve, a small amount at a time. 

This process was continued - slowly - until the color of the wort coming out of the tun was significantly diluted from its original almost opaque black (though this is not always the color of wort...this is just because we're making a porter) to a translucent brown.  We stopped adding water, allowed the wort already in the tun to drain into the kettle, and found that we now had what appeared to be more than six gallons of wort, allowing plenty for our next step...

TO BE CONTINUED