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Brewer’s Little Helper: Initial Thoughts on Yeast

——Update 5/1: I’ve added this fancy-schmancy glossary page in the hopes of making this blog accessible to newer, or even non-, brewers. If there’s anything I’ve missed that demands definition, let me know!——

Two weekends ago I caught my first glimpse of individual yeast cells at Manzanita. While I was thrilled to dive into some lab work, the impetus that compelled us to do so was not exactly joyful. It was getting towards the end of the brew day and we were finishing up a batch of Riverwalk Blonde. Garry harvested yeast from a finished batch intending to re-pitch into the latest brew, but life intervened and he ended up with a sample that resembled yeast soup rather than the viscous slurry he was expecting. Knowing that this didn’t look appropriate, he brought out the microscope to take a cell count. What we found was that we had nowhere near enough yeast. With no other yeast on hand that day’s batch would have to wait. Two or three days later he was finally able to introduce yeast into the wannabe beer, but it was too late. I had a taste of that batch last weekend and the flavor bore a remarkable resemblance to hot dogs. Unpleasant. We had little recourse but to dump that particular batch down the tubes. While it’s never fun to lose a batch, this experience served as my introduction to yeast quality control and as a powerful reminder of what “beer” becomes without the assistance of billions of yeast cells.

A Sample Cell Count

Sample Cell Count: The outlined cells are yeast, the dark blue cells are dead, the amorphous blobs are hops and protein.

Every good brewer, whether at home or in a production brewery, recognizes the importance of yeast. When it comes down to it yeast is what makes beer; brewers merely create the conditions for that process to happen. In fact, the chosen yeast and fermentation conditions have a greater flavor impact than any other single ingredient in the recipe. At a commercial level the key is consistency. Once Garry knew that the wort would have to sit overnight (we didn’t realize it would have to be several nights) we knew it would be problematic. Significant procedural changes made it impossible to produce a Blonde that was true to the brand Manzanita had established. The flavors produced by yeast largely depend on the temperatures employed and fermentation timeline. Wort is a perfect medium for growing yeast or bacteria, depending on what is introduced first, so brewers encourage yeast to gain a foothold as early as possible. When we failed to pitch at the appropriate moment we left a window that unwanted bacteria took advantage of. And that’s the recipe for hot dog beer.

I hope to make the microscope a more frequent part of the Manzanita brew day. It’s a standard industry practice to take a cell count, which notes not only the number of cells but also their health, before every pitch. Breweries harvest yeast from finished beer to re-pitch into their next batch. As they do this the amount of yeast and its viability varies from generation to generation. Knowing our cell concentration would help us come closer to pitching the same amount each time, which would in turn improve our batch consistency. I’m starting to gloss over all of this far too quickly, so I’ll cut myself off here for now. There are volumes that could be written about yeast and I promise to revisit the topic as we ramp up our lab program at Manzanita.

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Stewarding a Homebrew Competition in America’s Finest City (Drinking and paperwork make quite the pair)

February 22, 2011 Leave a comment

If this past Saturday morning was a reliable indicator, homebrew competitions are the following three things:

  1. Lively, at times bordering on raucous.
  2. Educational
  3. A fantastic way to spend a weekend.

I have to admit that I wasn’t really sure what I was getting myself into when I rolled up to St. Dunstan’s last Saturday at 9AM for the America’s Finest City Homebrew Competition.  As I approached the building I was stopped by a fellow QUAFF member who inquired about the tricky, google-inspired back road route he had seen me use just moments earlier.  We chatted for a few moments and I learned that he was Jim Crute, owner of Lightning Brewery.  I still react to meeting brewers as normal folks would when meeting rockstars, so this impromptu meeting bolstered my confidence that it would be a wonderful day.  I strode into the main hall to find a small crowd of somewhat familiar faces and a pleasant breakfast spread.

This was my first experience with a homebrew competition.  I hadn’t entered any beers, but I was there to volunteer as a steward in order to better understand the judging process.  Stewarding, it turns out, isn’t particularly difficult.  At the onset of the judging you pair up with a single category of judges.  In this case I got to choose, so I picked the Scottish and Irish Ale table.   You proceed to bring out the beers, one by one, until they’ve tried the whole flight.  After each beer you check the judge’s math — which gets pretty hairy as the day progresses — and fill out some last remaining paperwork.  Along the way you sequester the beers that have a chance of placing and remove those that obviously won’t make the cut.

The main take-away I got from the AFC is that stewarding is a fantastic way to train your palate.  I was hoping this would be the case, as my abilities to both discern and describe flavors need significant strengthening.  As judges make their way through their flight they are more than happy to let stewards in on their discussions.  I found that they are willing to answer questions if asked and will often encourage you to taste the beers after they’ve sipped enough to form their opinion.  As a steward you can read their scoresheets, which include separate commentary for aroma, appearance, flavor, mouthfeel and overall impression.  This is made particularly useful because you can often peruse the comments while sampling the beer in question.  I personally think that it’s the notably bad beers which are most interesting to taste.  They often serve as examples for various off-flavors, which are hard to find commercially and even harder to identify if you don’t have a BJCP judge sitting by your side.  Early in the day I had a good example of an infected beer that betrayed both acetic acid bacteria along with a possible Brettanomyces infection (For the uninitiated, the former instills a vinegar-like quality, while the latter is a wild yeast intentionally used in sours; neither should be present in any Scottish or Irish Ale).   When I brought it over to the “dumped” beer area the other stewards were eager to sample the infected brew.  This culture of beer nerdiness and serious study pervades the competition and makes the day fun for everyone involved.

Experiencing the judging process has me pumped for the first round of the National Homebrew Competition coming up in April.  I’m eagerly anticipating the feedback I’ll get for my submissions, which will hopefully include a Scottish Ale.  I’m also looking forward to stewarding once again.  If you’re looking for ways to expand your palate, learn off-flavors, or nail a certain style of beer, I can’t stress enough how great of a resource competitions can be.