High Alcohol Beers?

[Steven4est]

I just made a 12% alcohol beer and would like to go stronger if possible. Im guessing with extract brewing its near impossible, without being over 600 calories a beer lol. Any ways just wondering how strong you guys have gone up to.

[Ó Flannagáin]

11 is my max thus far, I believe evan! Really pushed it on one brew.

[Evan!]

It's not impossible, just difficult. I made an imperial stout that got up to 15%, but that's as high as I've gotten it. It's like motor oil and finished around 1.038.

One thing you gotta do is to use the super high gravity yeast (or the trappist high gravity) strain. The second is to brew a full-size starter batch and then brew the big guy as soon as possible after that starter batch is done fermenting, because you start to lose cells very quickly. The third is to use tons of simple sugar and to not add all your sugars to the boil....meaning you reserve some extract and dextrose (for example), then once the beer has fermented down some, you add it then. The reason for this is that yeast get highly stressed because of osmotic pressure (dense wort due to high sugar concentration), so if you keep the overall gravity ceiling relatively low, that will help keep your yeast healthy and increase your chances of getting full attenuation. You also will need to mash very low, like 146-147f, for 2 hours. And be ready for a 3+ hour boil if you're doing partial mashing. Lastly, for some reason, the super high grav strain (and possibly others) tend to hold onto their CO2 for some reason. I'd see a drop in airlock activity during fermentation, and swirl the carboy around, and it would go crazy, so much CO2 coming off that the airlock was literally spraying me in the face. I can't imagine it's healthy for all that co2 to stay dissolved in solution during fermentation (then again maybe I'm wrong), so keep an eye on that.

[ohiobrewtus]

There are certainly easier ways to get abv higher than that, but if you still want a good, flavorful beer while breaking the 12% mark then I would recommend the steps that Evan has laid out here.

[fireballmatt]

Straight from Wyeast Labs...here's their rec's

Brewing beers with high original gravities (above 1.065) requires some modifications to normal brewing procedures. Factors that will determine success or failure in high gravity brewing are pitch rates, nutrient addition and oxygenation.


Pitch Rates
Increased wort gravity causes increased stress on yeast due to increased osmotic pressure and increased alcohol levels. It is necessary to increase your pitch rates when increasing the wort gravity. A general rule of thumb is to pitch one million cells per milliliter per degree plato. So a 20 degree plato (1.080 s.g.) wort would require 20 million cells per milliliter per degree plato.
Home brewers will either need to pitch more packages of yeast or make a starter. When using an Activator 125ml package, 1 package to 5 gallons will give around 6 million cells per milliter. This is clearly too low for high gravity brewing and will cause inconsistent results and usually high terminal gravities.


Nutrient
Essential nutrient levels are typically reduced during high gravity brewing. This is a function of either increased binding of nitrogen during boiling or dilution of essential nutrients by adjunct addition. Additions of Wyeast Nutrient will restore essential nutrient levels to provide healthy fermentation.


Oxygenation
As wort gravity increases, solubility of oxygen decreases. It is very important to compensate for the decrease in solubility by oxygenating more aggressively. When brewing high gravity beers, it is best to oxygenate with pure oxygen through a scintered stone.

In addition, you will also want to give"big" beers a longer bottle conditioning time and use slightly less priming sugar than normal. There's still complex sugars that over time will break down and provide fermentables for conditioning. Some people recommend that if you are going above 15% that you allow 6-9 months to condition.

Another trick is to ferment peacemeal, brew each batch of wort over the period of a week or two, adding each batch to the pot as the yeast ferments out. This sustains the fermentation by adding new fermentables but not so much at one time as to overtax the yeast.

Any way you do it, it calls for more attention and care to the fermentation than you would have normally.