Thursday, 29 November 2012

Drinking with Santa

A Pint of Bad Santa 2012
While it is still too early to seriously start drinking, the giant pooch-screw that was this years Bad Santa brew session  concerned me.  As such, I'm trying Bad Santa a month earlier than I should, to see what it has become.

The pour is good - a nice, long-lasting rocky head forms, and is accompanied by an aroma dominated by ginger, but with detectable hints of malt, honey & cinnamon. The beer is darker than expected, but this was expected given that I had to decoct a few times to get mash temperatures to where they were supposed to be. Despite using irish moss in the boil and gelatin in the keg, this beer has a bit of a haze.  I nerded out and tested a sample at work.  No yeast were seen under the microscope, eliminating suspended yeast as the suspect.  An absorption spectrum did not reveal a strong absorption peak at 280 nm (the absorption peak of tryptophan), making a protein haze unlikely. The addition of iodine created a weak absorption peak at 580 nm, meaning that residual starches are the most likely culprit1.  Given the mash issues I had, the presence of starch is not unexpected, but oddly, the iodine test of my mash was negative.

Wednesday, 28 November 2012

Yeast Banking IV - Starter Tables

So it appears my post on stepping up to a pitchable amount of yeast created some confusion (and has an error).  Here are some simplified tables to lead you through the process.  The days of the week are set-up for how the London Homebrewers Guild yeast banking operation works, but the tables are easily adaptable to any schedule.

For London Homebrewers Guild members reading this post, anything in italics is done by the yeast bank's yeast wrangler (i.e. me).

For Ales with a Starting Gravity Less Than 1.060
This will produce ~180 million cells, assuming yeast is grown using a stir-plate at 22 C to 24 C.
Day/Time Step Cells at End of Step
Before Monday AM Send me a PM on the board requesting yeast0
Monday AM Start 7 ml culture from frozen stock125-175 million (0.125-0.175 billion)
Tuesday PMPickup 7 ml cultures (from my house, or at Guild meeting).  Pitch into 250ml or 1.040 wort with stir-bar; grow 24 hours4 billion
Wednesday PM Pitch 250ml starter (plus stirbar) into 1.25L of 1.040 wort.  Grow for 24 hours 48 billion
Thursday PM Put starter in fridge, let yeast settle overnight 48 billion
Friday AM Pour off starter, replace with 1.5L of fresh 1.040 wort.  Stir for ~12 hours 185 billion
Friday PM Place starter in fridge. 185 billion
Saturday AM or Sunday Pour off all but a small amount of starter, swirl to suspend yeast and pitch into beer (use magnet to avoid pitching stirbar). 185 billion

For Strong Ales (Starting Gravity Greater Than 1.060) or Lagers
This will produce ~380 million cells, assuming yeast is grown using a stir-plate at 22 C to 24 C.
Day/Time Step Cells at End of Step
Monday-Saturday Follow the steps in the above table upto Friday PM185 billion
Saturday AMPour off starter, replace with 1.5L of fresh 1.040 wort.  Stir for 24 hours380 billion
Sunday AM Place starter in fridge. 380 billion
Before BrewStarter is stable in the fridge for 1 week; before pitching pour off most of the starter and swirl to suspend the yeast.  380 billion
Note 1: For best results (lager or high-gravity beer), it is best to pitch active yeast.  The easiest way to do this is to pour off the starter, add ~500ml of fresh wort, and stir for 2-4 hours at the planned pitching temperature.  This will get the yeast past their stationary phase and allow you to pitch yeast at high krausen, but with a minimal amount of starter wort (which tends to taste bad).

Note 2: If you have a 4L flask, the above process can be performed using a 3.5L starter in place of the 1.5L starter, producing 562 billion yeast - enough for a high-gravity lager.

X-Mas 6-Pack 2012

In the past I've always used Christmas as an opportunity to share my homebrew with friends and family.  While my success at getting new people into the hobby has been less than stellar (currently standing at zero), it at least has got people to try some new beers.

This year I'm taking it to a whole new level, and am sending out sample 6-packs, containing three different beers - two bottles each of Bad SantaCrepuscular Porter and 1040 Special.  And I've designed a series of labels for each beer.  Click to see the full-sized images.

Tuesday, 20 November 2012

1040 Special Bitter

Sunday was brew day again.  This weeks beer is an English-style special bitter; a slightly more alcoholic version of the classical bitter that I so enjoy.This recipe seeks to replicate the English style at every turn - from using classical English Maris Otter malt as a base malt, to the classical East Kent Goldings hop, to the use of a Burton ale yeast; a yeast which provides the higher esters which typify English beers.

This beer was my first to take advantage of the new yeast bank I am running on behalf of my brew club, the London Home Brewers Guild.

No pictures this time around, just the recipe.  The brew session went flawlessly; I even hit my gravity dead-on - 1.040.  Hence 1040 Special...

Monday, 19 November 2012

Yeast Banking III - Stepping Up To Pitchable Amounts

The last two of my posts on yeast banking covered methods to aid in the logistics of running a large bank, and covered how to prepare the frozen stocks.  In this third instalment of my yeast bank series I will cover how you go from a frozen stock to a quantity of yeast sufficient for pitching.

Firstly, how much yeast do you need to pitch into a beer?  The answer is 'it varies'.  Strain-specific characteristics, volume of beer you are pitching into, the specific gravity of the wort, the yeast quality, and the planned fermentation temperature all effect the number of yeast required. Calculators like Yeastcalc and Mr. Malty provide a good idea of what you need, although in many cases the number provided by these calculators are over-predictions.

This article assumes that you have the capacity to handle starter volumes of at least 1.5L (i.e. a 2L jar or flask), a stir-plate, and (ideally) dry malt extract (DME) plus yeast nutrients.

In this article:

  • How Many Yeast Do I Need?
  • How Do I Maximize Yeast Quality?
  • Growing A Starter.
  • I Don't Have A Stir Plate - Now What?

Tuesday, 13 November 2012

Yeast Banking II: Methods to Manage the Bank

As discussed in my last article, I am now managing a yeast bank on behalf of the London Home Brewers Guild. In the previous article I outlined the methods we use, and the rational behind using those methods over other conventional methods. In this post, I will outline how the bank itself is run, with detailed protocols for the clean-up, freezing and “withdrawal” of the yeasts.

As mentioned before, these methods have been implemented assuming you have access to the facilities available in a biology lab – i.e. biosafety cabinet, micropipettes, autoclave, etc. In the future I hope to post an article on how this method can be implemented using the kinds of equipment the average home brewer can access.

Methods in this article:
  • Preparing & freezing the yeast
  • Checking for contamination
  • Secondary cleanup
  • How to perform a withdrawal
  • Counting yeast

Monday, 12 November 2012

Yeast Banking I: Managing A Large Bank

Safale S-05 from our yeast bank,
bacteria-free & ready-to-pitch!
On the web one can find - literally - thousands of articles on yeast banking; the storing of yeast for long periods of time for use in future batches of beer. Depending on exactly what the brewer is trying to do, this can involve anything from pitching a new beer on top of a the yeast cake left over from the last batch, to collecting yeast from the kraussen of a fermenting beer (top-cropping), to yeast washing, to storing yeast on agar slants or frozen in glycerol-containing liquid media.

All of these methods have their pluses and minuses – including equipment limitations, difficulty, storage life, and a variety of other factors. I am fortunate enough to run a biology lab, and thus have access to tools and methodologies not easily accessed by most home brewers. As such, I am using these resources to maintain a yeast bank for my brew club, the London Home Brewers Guild, in which we are banking as many yeast as we can manage. As part of this process I am writing a series of protocols and articles to inform my club as to how the bank works. Many of these articles I will simul-publish here on my blog, for those on the web whom are also interested.

This first article is a brief intro into our yeast bank. I will follow this article in soon (edit: here is is!) with a detailed method (with pictures!) of how we bank our yeast, ensure they are free of contaminating bacteria, and distribute the yeast to members.

More below the fold...

Thursday, 8 November 2012

Ummm, porter

So the Crepuscular Porter has been in the keg a few weeks and it has come out fantastic.  Its a bit darker than I anticipated - I was expecting a dark nut-brown, but instead its  as dark as any stout.  But that aside, its otherwise exactly what I was hoping for.  In many ways, it has exceeded my hopes.

This porter pours with a thick, creamy head, that does the "Guinness thing" where bubbles of beer appear to move downwards.  This quickly subsides into a thinner, but long lasting head that leaves strands of Belgium lace down the sides of the glass.

This head overlays a brew with strong malt-notes, that has hints of nuttiness and coffee-like roastiness.  Unscarred by any hop aroma, the slight fruitiness of the British ale yeast is detectable among the strong coffee and nut aromas.  The smell is so enticing that I have, on occasion, almost forgot that I'm supposed to drink it.

Every sip of this beer is heavenly.  It is silky on the tongue, with malty sweetness nicely balanced by subtle, but noticeable hop bitterness.  Despite the (relatively) large amounts of darker malts, there is no detectable astringency.  This beer featured light chocolate malt - a rarer malt that is slightly less roasted than conventional chocolate malt.  The impact of this malt is profound - while the beer still has a dark colour, the usual in-your-face roasted flavor and its accompanied astringency is missing.  In its place is a mellow, and entirely pleasant, nuttiness.  It makes for a much smoother and easy-drinking brew.  This mellow nuttiness, combined with this beers modest body, means that unconsciousness, not a heavy stomach, limits how many pints one can quaff in a single sitting.

Bad Santa's Bein' Naughty

So its time to keg bad santa, but things are not what they should be.  What should be a clear beer remains cloudy.  Given all the bad things which happened, I shouldn't be surprised that things are not 100%, but still...

The problem may not be obvious in this photo, but the beer remains cloudy - this should be an amber-coloured beer with a bit-o-red in the colour.  It is that colour, but there's also a lot of haze, making it look darker than it should be.

Why is the haze there, why won't it go away?  Short answer is . . . I don't know.  Hopefully its protein or yeast - a bit of gelatin at kegging will pull that out.  But I fear it may be starch - which no force on earth will get rid of.

Hopefully it'll still taste good, but this may be a beer to drink out of a ceramic tankard.