Co2 Toxicity - Capping timeline
I have always thought Co2 Toxicity was a bunch of BS, i have had other brewers concerned that i harvest yeast from a tank under pressure.
I had the opportunity to speak with Chris White at the Hopunion Hop & Brew School this year and asked him about this topic. To sum up his answer, assuming you are capping, bunging, spunding whatever you call it at the end of primary, up to 15 PSI (1 Bar) should not have any detrimental effects on yeast. Pressures over 20 PSI could cause problems with yeast.... or your tank for that matter
I usually attach my barby-kuhner (set to 15 PSI or 1 Bar) the third day of fermentation when i still have slight blowoff activity, 2-4°P > terminal. With my Hefe, if i still smell any sulfur i wait to cap, or don't at all to let it blow off otherwise i end up scrubbing by means of a violent x-fer to the BBT which releases all of the Co2 anyway.
Originally Posted by MaltAlchemist
-a side note, it is difficult to acheive full carbonation by this process in ales because when you crash the tank more Co2 goes into solution and 15 PSI @ ferment temp turns into +/- 7-10 PSI @ conditioning temp. The amount of head space in the FV obvioulsy plays a role in this but i usually get my ales about halfway carb'd. Lagers on the other hand you may be able to get 80-90% carb'd - but watch out for sulfur...
Last edited by Jephro; 10-20-2009 at 04:39 PM.
Jeff Byrne (aka jephro)
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