Last time, I left off by noting that my beer was chugging along nicely.  However, I had reached the upper limits of the yeast type that I used, so what was I to do?  Did you know that WLP 1099 has a fermentation potential of 25% ABV?  That’s crazy.  I didn’t add this at first because I wanted to really focus on normal yeasts as the backbone of the beer.  However, as I mentioned before, I realized that I would not reach that goal because of wort viscosity (i.e., it was too thick).  However, I knew that I could get it higher than it was, so I embarked on making the alcohol climb to a higher percent.  What else could I do?

After making a big starter, I added my yeast to the hostile 15% ABV, thick, and uninhabitable environment of my beer.  Unfortunately, my direct pitching didn’t have the effects that I wanted, and I only gained a percent or so.  This was my second error.

Then it struck me. Why didn’t I use a continuous feeding method instead?  What I mean is this: if I had a high yeast to solution ratio, I could raise my ABV in a small container and prepare my yeast to the larger environment.  What I decided to do was to draw about a pint or so out of the big fermenter and add it to the one gallon fermenter , which had a tube of yeast in it, on a daily basis.  The large amount of yeast per solution would ferment the beer and acclimate to the environment, and then I could add it to the larger solution.  It worked like a charm, although I think next time I would keep the gradual feed going and move to a two gallon fermenter, three gallon, and so on.

This wasn’t the only problem.  Given the thickness of the beer, my ability to get oxygen into the beer was very restricted.  Thicker beer has a harder time allowing dissolved oxygen.  I wish I had a tank of of pure oxygen, which is far more soluble than ambient air given the nitrogen content of “natural” air.  As you can see from this and the last post, the thickness of the beer ended up being a recurring theme. However, I had a great degree of success despite the flaws in my process.

After feeding the multiple yeasts (London, Trappist, Merlot and Super High Gravity yeasts x 3), I had a beer that finished out at 20.3762%.  The beer still had enough sweetness to balance the ABV.  In fact, that beer is lovely and thick.  Had I thought of it before, I would have built the yeast up through feeding sugars gradually (instead of the higher initial amount) and thickened the beer at the end.

This would have done a couple things.  First, I would have been able, I believe, to come much closer to the 25% mark specified by the manufacturer.  Second, I would have had a much easier time in my eisbock process.  My thickness affected my ability to freeze the beer to the desired level.  Again with the thickness. Of course, I was content to wait on the beer for a while and decided to do a few extra things in the meantime, including adding some stuff to the brew…the subject of the next post.