Pressurized Fermentation???

[JCasey1992]

Hi all!

So I have the best father ever who just got me a Fermentausaurus for my 25th birthday last Monday. I just purchased the optional pressure kit and plan to brew a NE IPA with it using a pressurized fermentation. Considering that I have been using nothing but brew buckets for the last three years and know little about a pressurized fermentation, can someone walk me through how to do it? I believe I have all the pieces (fermenter, spunding valve, and pressure kit) but a description of the process would be appreciated.

Thank you in advance for the help. As always, you guys are great!

Cheers!
Casey

 

[xico]

Congratulations on the new vessel!

Some others will no doubt add more than what I can offer but I'll share what I know. There is a schedule to pressure additions that affect flavor and CO2 content.

You can either:
Yield most of your CO2 through the fermentation and then "top off" with a CO2 tank if needed. I see you have a Hefeweizen in your future brews and that will likely need more. But if you don't want the isoamyl acetate to take over the wheat some pressure during fermentation could balance things out.

The alternative to using CO2 would be to transfer in either new wort or boiled dextrose and set the spunding to your appropriate pressure.

What's to be gained in the choice?
Ester production is restrained with headpressure in the conical. This could be desirable for some styles. Another feature of pressurized fermentation in a concial is more active by convection meaning the yeast will swirl in solution a little longer but can attenuate a beer in a shorter period as a result. This doesn't mean they are conditioned yet but you can bottle off terminal beers with a counter-pressure device and free up your fermenter in a matter of days.

Research brewers I know use spundings to yield ~50-70 percent of their CO2 through rises in pressure allowance. They then use the tank. A brewer in Germany said they start high and their yeast can handle it. It would require some experimentation to determine how far you can push it.

Early pressure seems to range between 3 and 15 psi. If you want maximum ester character I would add the spunding at the end of primary. for simply CO2 production 1-2 plato away from expected FG is sufficient to crank up the PRV.