Pressure fermenting high gravity beer

[ILMSTMF]

Hello,

It's been a while since I worked with a high gravity beer that is not dark. I've got a 1084 hazy NEIPA in FV (Fermzilla All Rounder). There will be a single dry hop dosing of 10 oz and I plan to add those close to date of keg transfer. Had some questions I thought some friends could help me with, please.

• Would it benefit the beer to keep in primary for a month?
• When should I remove airlock (blowoff tube) to build pressure in FV?
• If I spund, I'll be doing myself a service versus letting it build as much pressure as possible (without a spunding valve attached). If my statement is true, how's 10 psi?

Thanks in advance.

 

[Franktalk]

Hazies are supposed to be drunk fresh, so I wouldn't keep it much after it is done fermenting. You would only be getting the staling process started.

If you are spunding for the purpose of carbonating it, you will need to begin near the end of fermentation when it is a few points away from FG.

You wouldn't want to "[let] it build as much pressure as possible" as it may explode.

What do you hope to gain by fermenting it under pressure?

 

[Bassman2003]

Pressure fermentation is based upon personal preference and experimentation. I do my WCIPAs at 2 bar as in my experience, the more pressure you have on, the more the hops pop. But this also includes the bittering hops which might not be the best for a NEIPA. You might want to research that.

BTW, one drawback of pressure fermentation is that you need a lot more yeast the higher you go. But the flavor can be worth the effort.

 

[ILMSTMF]

What do you hope to gain by fermenting it under pressure?

Two things. A bit of carbonation in the beer and a "free CO2 supply" for the upcoming cold crash. I probably don't need to say this but, for anyone who isn't aware, CO2 during a cold crash is vital. In past, I have forgotten to charge the FV with tank CO2 prior to crashing. Wound up with a partially imploded FV. Thank you.

the more pressure you have on, the more the hops pop. But this also includes the bittering hops which might not be the best for a NEIPA

Terrific points.

one drawback of pressure fermentation is that you need a lot more yeast the higher you go. But the flavor can be worth the effort.

Another great point. I've got a lot of yeast in this batch, FWIW. Of the yeast cake from my last batch, I ended up taking 5/8 of it. I admit, could have gone with less but a certain catastrophe on kitchen counter lead to that. Thank you.

A crucial note - I don't ever allow the pressure in FV to get "too high". On average, the airlock is removed after a week or so. Another week will pass and, again, on average, I'll wind up with 10psi.

 

[IslandLizard]

Pressure fermentation is based upon personal preference and experimentation. I do my WCIPAs at 2 bar as in my experience, the more pressure you have on, the more the hops pop.

You've got me curious, being an old hop-head.

2 bar = 29 psi!
When do you start it, and at what temps?

The pressure also causes high(er) carbonation. Aren't higher levels of dissolved CO2 poisonous to yeast?

 

[Bassman2003]

Yes, the higher pressure is tougher on the yeast but does not kill them. This stress gets them to excrete glycerol (if I remember that correctly) that gives the beer a little thicker mouthfeel. This amount of pressure closer emulates large CCVs that big breweries use that have a lot of hydrostatic pressure.

The key to making this work for the hops to pop is imho, filling the fermenter with CO2 right after you pitch the yeast. So I pitch, oxygenate, close the fermenter and pressurize the fermenter to 30PSI with tank gas. This will be absorbed down to ~20ish PSI but the fermentation gas raises it back up to 30PSI for the remainder of the ferment. Some CO2 does need to be bled off for end carbonation levels.

I start the ferment around 65-66F and ramp it up to 70-72F over a little time. This is an area for experimentation for sure. This is with normal Chico yeast.

First time I tried this it was like - that is how they do it! Tastes like retail IPA...