Beer Forum

I am going to brew a RIS next weekend and since it is our 100 brew, we are gonna go big. Looking to hit OG 1.15 with a SG between 1.032-35 So my point is that I have a very healthy yeast cake of WLP001 which I will be removing 2000 ml tomarrow and growing to 3000 over the next week. Has anyone reached into the 15% with the WLP001? I have had success up to 13% and am wondering if I may be overdoing it.

PS will have some WLP099 ready to go if needed. Just hoping to hear some success stories to ease my OCD

Really? Nobody out there?

I havnt done it, but im sre its doable. You might have to rouse he yeast part way through the ferm, but should be able to handle it I would get.

On a beer that big I assume you plan on using at least some sugar. If so, don't put it in the boil. Go ahead and begin to ferment the lower OG wort as normal. when the gravity drops by about half boil up about pound of sugar in a quart of water, cool and add to the beer. Repeat this until you have added all the sugar from your original recipe.

Extremely high gravity worts put very high osmotic pressure on the cell walls of the yeast and stress them heavily. This will cause the yeast to stop working prematurely. By incrementally feeding the yeast, the yeast never sees the high gravity even though it ends up eating the same amount of sugars. This will help avoid some of the stress and help you achieve a lower FG. You will also want to mash a little on the low side (148-149°). If you are doing an extract brew, make sure you are using a highly fermentable extract like United Canadian or Briess. Avoid Laaglanders or John Bull unless you are using at least 20% sugar. Adding extract during fermentation is another way to incrementally feed the yeast.

Wayne
Bugeater Brewing Company

Bug,

Sam Calagione recommends a similar feeding of the yeast in his book Extreme Brewing. Where you daily add a little bit of sugar to the primary. Seems like it would make it difficult to really know the original gravity, but it would help the yeast do its job.