Monday, June 10, 2013

The Perils of Partial Mashing, or How Azog the Defiler Got His Name

Thus begins the second part of the story of the beer that would become known as Azog the Defiler.

As described before, this beer was originally conceived as a Southern English Brown Ale, with toasted oats and underlying raisin notes, and was supposed to remind the drinker of eating an oatmeal raisin cookie.  This was my first custom recipe, but I had high hopes.  Alas, it was not to be.

It was a Murphy's Law sort of brewday, which only compounded my trials as I ventured into the world of mashing. As I mentioned in a previous post, it appeared that Mosher's book was calling for a partial-mash recipe.  It was called a partial-mash, anyway; there was no extract or extract-with-specialty-grains recipe listed, and Mosher gave specific instructions for how to do a partial mash recipe.  So, despite the fact that it looked to my untrained eye like an extract-with-specialty-grains recipe (which just requires steeping the grains for a little bit before the boil), I followed Mosher's instructions for partial mashing.  I followed them, in fact, even though BeerSmith was setting off alarm bells, saying that if I treated it like a partial mash the original gravity was going to be way too high.  Besides, so what if the OG is a little (or a lot) high?  It will have a little extra alcohol.  Nothing wrong with that, right?

It turns out that is not the case; different strains of yeast have different tolerances for alcohol and differing abilities to chew up sugar in the wort.  In addition, a heavy alcohol presence can be hot or solventy if you don't handle it correctly, and it's also not appropriate for most styles (barleywines being one of the exceptions; more on them later).  But that's a problem that I didn't have to deal with until later.

The first step in transitioning to partial-grain or all-grain brewing, of course, is getting the right equipment.  I had gotten a pretty large (7-gallon) brewpot with my original equipment, so I was sitting pretty there, and I figured I could use kitchen pots for my sparge water.  All I really needed was a mash/lauter tun.

For anyone who's unfamiliar with all-grain brewing, the central vessel is called a mash/lauter tun, or MLT.  This is the vessel that holds the grains--you steep them in carefully temperature-controlled water for about an hour, depending on the style (it's possible to get much more complicated, with steps and rests and multiple temperature changes, but it's generally just one steep in water between 150-155 F).  This is called the mash.  A decent MLT will have a drain valve and a false bottom to keep the grains away from the valve.  Draining the liquid out of the MLT is called lautering.

In addition to the MLT, you need a vessel capable of holding and heating several gallons of water for sparging, or rinsing the grains in the MLT, and another vessel capable of holding the total volume of liquid for the boil.

At this point all I really, really needed was an MLT.  I decided to go with a round cooler-style 5-gallon homemade tun.  The advantages were that it was relatively inexpensive, easy to assemble, and flexible.  The only real downsides were that there was some assembly required, and I would need to get a bigger one if I got into doing large all-grain batches (bigger than 5 gallons) or high-gravity all-grain brews (like barleywines and the like).

Finding the cooler wasn't particularly difficult, but like with all projects the cost I found was a lot higher than online guides said it would be.  Assembling the brass for the valve, on the other hand...I spent a week and easily a hundred dollars buying, testing, and arranging connectors.  My local Home Depot and Lowe's didn't have all of the pieces I needed (particularly washers), and being relatively new to brass plumbing features I underestimated how many similar-but-incompatible styles there are.  Thankfully Home Depot will accept returns even of opened items, but I still ended up with probably $20 worth of brass that I couldn't find the bags for despite careful organization.  I eventually broke down and ordered a $25 pre-assembled kit.  It was about twice what it would have been had I been able to find all the parts, but a quarter of what it cost me to try it myself.

Finally my mash tun was assembled, and I ordered the ingredients from Northern Brewer for my Oatmeal Raisin Cookie brown ale.  I've had good experiences with them overall, but this time I opened the box and everything was there...except for the pound of rolled oats, which is kind of central to the recipe.  So off to the store I go.  My local homebrew store (MyLHBS) was closed by this time, but I'd heard that quick oats would work just as well.  Turns out Quaker Quick Oats are just about a pound, so it was perfect.  I poured them on a baking sheet and popped them into the oven for a few minutes.  They browned a lot quicker than I'd been told to expect, though, so I might have overtoasted them a little.  I'm not really sure.  After toasting they need a couple of days rest to get rid of some nasty aromatics, so I stuck them in a paper bag and let them rest.  (Addendum: NB was very quick to send me out a pound of rolled oats as soon as I alerted them to the problem.)

I was oh-so-careful in starting my yeast starter.  Exactly eighteen hours before I anticipated needing to pitch I started my starter.  I boiled up the correct amount of dry extract, cooled it, pitched the yeast, and stuck it on the stir plate. 

The next day I got everything set up.  I added my grains to the mash tun and started heating up my mash water.  Once it hit the target temperature (167.5 F, which should cool to 156 F once it was added to the grains) I added it to the grains and stirred.  It seemed rather thick; I suspect I fell significantly below the 4.75 quarts during the boil (a lot of water probably boiled off).  After about five minutes the temperature was below 150, so I boiled another several cups of water and added it.  Five minutes later it was still low, so I repeated the process.  I checked halfway through the mash, and the temperature was way too high (maybe in the 170's?), so I added some cool water.  I don't recall the exact numbers or times but it was a mess.  Temperature control was probably my single-biggest problem during this ordeal.

I say that temperature control was the biggest problem I had with this brew, but whether that's true depends on whether you think a lack of temperature control was responsible for what happened next.

Generally what happens next is you open the tap part-way and collect what are known as first runnings.  The first stuff out of the mash tun generally has a lot of husk and other particulate matter in it.  You collect it and pour it back into the tun until it runs somewhat clear.  Mine never really did that.

In fact, mine hardly ran at all.

The most dreaded thing in all-grain brewing is known as the stuck sparge.  That's when the grains form a tight, compact bed and let very little liquid through, and the draining slows to a trickle.  I could hardly work my way up to that.  I would open the tap (part-way; opening it up too fast is one of the leading causes of stuck sparges) and get a slow flow for a few seconds, then a trickle...and then a drip.  Closing and re-opening it would restart this process as long as there was a lot of liquid in there, but mostly vigorous stirring/scraping of the contents of the tun is the only thing that got any liquid out.  What I did manage to extract was sludgy and thick with particulate matter.

I spent hours trying to drain this liquid.  I added the sparge water early in hopes that a higher liquid/grain ratio would ease things (it didn't).  I stirred.  I pleaded.  I adjusted the tap.  I begged.  Nothing worked.  Finally around 11pm I posted a query on HomeBrewTalk (God bless these people): am I doomed if I just cover the wort and do my boil tomorrow?  The quick consensus seemed to be I would probably be all right, although there was a slight possibility of some off flavors.  I laughed.  After this ordeal, their minor concerns were the least of mine.  I covered the kettle with aluminum foil and trudged off to bed.  Did I mention this was a weeknight, so I was getting up again in a few hours?

I mentioned earlier how carefully I timed the creation of my yeast starter.  I wanted to pitch it eighteen hours after I started it: no more, no less.  Except I'd just added another twenty-four hours to that.  Eighteen, forty-two; what's the difference?

My yeast had kind of a greyish color and smelled a little sour when I checked on it the next day, although it otherwise seemed healthy.  Hopefully that won't be a problem.  The boil itself was not so bad--even I can't screw up a partial-volume boil too badly.  Unfortunately, the stuff I ended up transferring to the carboy for fermentation was thick with particulates, and it was only the homebrewer credo of "relax, time can fix almost any problem" that kept me from pouring it down the drain.  Eventually I would almost come to wish I had.
To Be Continued...

No comments:

Post a Comment