Fermenting under pressure

[ChristinaS1]

So the fermentation is going well. The new pressure gauge has fixed the spunding valve. I am using 15PSI this time. I have always used 8-10PSI in the past and am curious if I will be able to taste a difference.  Have any of you?

Something you can do with a spunding valve is check to see if you have a gas leak in your system: put in a high amount of gas and see if the needle drops. I want to try that sometime on my other two kegs.

Cheers,

Christina.

[Pezzza]

On 7/25/2020 at 8:39 AM, MartyG1525230263 said:

with one using W34/70 and the other Urquell 2001 both as 15psi and 22c

Do you cold crash before kegging ?

[Marty_G]

1 hour ago, Bearded Burbler said:

Do you cold crash before kegging ?

Some times but in general terms I thing of kegging and storing/lagering at  close to 1c as cold crashing in the keg.  So a bit from column A and a bit from column B... 

[Pezzza]

22 hours ago, ChristinaS1 said:

I am using 15PSI this time.

My recent foray on a lager style brew was 12-15PSI... at c.22degC with W34/70 and pretty happy with the outcome...

[ChristinaS1]

Question. After fermentation is complete, do you see the needle on the pressure gauge drop? Mine has and this does not seem right. Wonder if there is a leak somewhere? What do you guys think?

[Marty_G]

2 hours ago, ChristinaS1 said:

Question. After fermentation is complete, do you see the needle on the pressure gauge drop? Mine has and this does not seem right. Wonder if there is a leak somewhere? What do you guys think?

Yes that is normal. It will slowly drop as the CO2 in the headspace is absorbed as none is being produced.   Another indication that ferment has finished the temp will drop.   I use a stainless FV and these are great indicators.  I use a heat belt to regulate the temp and nearly all brews will increase beyond what I have set it at.  Once ferment is over they will reduce to the temp that the InkBird is set at.  The last Pils I made using Urquell 2001 was set at 22c and the temp rose naturally to 26c.  After about 3-4 days the pressure and temp  started to drop.  That is when I take a gravity sample.  It is usually at FG by then.  I leave for 24-48 hours then go my next step either keg or cold crash. 

[Marty_G]

11 hours ago, Bearded Burbler said:

My recent foray on a lager style brew was 12-15PSI... at c.22degC with W34/70 and pretty happy with the outcome...

W34/70 handles pressure well.  They are drinkable in about a week and great after about 4. 

[ChristinaS1]

Having the first taste of my pressure fermented Perle Lager (60gm Perle at FO x 20 min stand). It is interesting. Not noticing any of the soft fruit (apricot, plum, canteloupe) flavours the fellas on Basic Brewing radio mentioned but is does taste different than my other lagers, which I can't describe. I am not over the moon about it, but it is okay. 

In spite of being fermented with Coopers ale/lager blend, this tastes like a lager, with a slight sulphur-y note. I suspect the higher PSI used this time (15PSI vs my previous 8PSI) might be responsible. 

Still a little cloudy. Just added the gelatine yesterday. 

Cheers,

Christina.

[Lettucegrove]

I'm looking to ferment an ale in a keg with hope of serving straight from the keg and also carbing the keg with the co2 produced from fermentation. Can anyone give me some tips on pressures/time frames etc?  

[Marty_G]

@LettucegroveIf that is the plan I would ferment at a higher pressure, maybe 20psi. The pressure in the keg will drop when you chill it but it will be hooked to the gas anyway.  Use a floating dip tube. If you dont and use the dip tube that is already in the keg you will be pulling several litres of trub before you get a decent beer.  

 

[Lettucegrove]

Thanks @MartyG1525230263 i'll round up a floating dip tube and experiment. 

[ChristinaS1]

Hey @Lettucegrove. Which ale yeast are you using? I would avoid using Coopers dry ale yeast, or the ale/lager blend. 

Thanks to @MartyG1525230263 and @iBooz2 I think I figured out the cause of the off flavours of my last pressure fermented brew (see the "Stale flavour" thread). I used two packs of the ale/lager kit yeast (comes with the Mexican Cervasa and APA), fermented it at 18C, and under 15PSI, which I applied immediately after pitching and topped back up to 15PSI when it dropped post-fermentation.

I was speaking with a friend of mine who is knowledgable about yeast and she said that distiller's yeast can throw funky flavours when fermented too low or too high. Cooper's dry yeast was derived from distillers yeast. I think that being fermented under 15PSI from pitching, at the low end of its temp range, stressed it out and caused it to throw funky distiller's yeast flavours. 

It is possible that Coopers dry ale yeast would be fine in a pressure ferment if the temp is higher, and/or the pressure is not applied immediately, and/or a lower PSI is used, but I am not going to try to figure it all out. I will never risk using Coopers dry ale yeast in a pressure ferment again!

Cheers,

Christina. 

Edited August 10, 2020 by ChristinaS1

[Lettucegrove]

@ChristinaS1 I'll use US05

[Titan]

one of the things that hacked me off about closed transfer was the cleaning of the transfer line. Here is a tip for cleaning that line. Kegland do a tee piece and plastic carb caps. You need 3 caps and a tee for around $15. Oh you also need a standard soda bottle and a small piece of line. Gas in right, Starsan out the top and your third cap goes to waist water. Only need a couple of psi to do this.

[PaddyBrew2]

Really good tip cos I was stumped on how to clean them other than snipping the ends off , removing the fittings and washing. Which means losing cm's of line each time 

[Shamus O'Sean]

I use a garden sprayer with the wand cut off and replaced with one of the orange carbonation caps.

See post for more details:

 

[Journeyman]

15 hours ago, Shamus O'Sean said:

I use a garden sprayer with the wand cut off and replaced with one of the orange carbonation caps.

I have one of those but I didn't cut the wand off - the 8mm gas line fits straight in the nozzle with no leaks. So I can also use it to put perc into kegs etc.

 

[Frankie4Fingers]

Whilst I see a few people using Pressure Fermenting as a way to ferment at higher temperatures, is there a downside to not increasing the temperature but still fermenting under pressure?

I have a Munich Helles that is just starting to move now having pitched 2 x SafLager W-34/70 into it on Sunday.  The SV is on and I plan to let the pressure rise up to ~ 10PSI but I am keeping the temperature at about 12.5C initially.  I will then increase the temp when it gets to around 10 points from FG to perform a diacetyl rest.

The main reason I have been using pressure fermenting is to naturally carbonate so that the beer is ready for consumption quicker without generally needing 2 weeks on the gas after kegging. (I know you can force carb or go with 12 hours at 40 PSI etc which I sometimes do).   Given this is a Helles I plan to try and condition for 6 weeks or so before I go anywhere near it so it cleans up nicely.

Anyone have an idea if fermenting under pressure but following standard temps for the yeast would cause any effect to the beer itself in terms of flavour?

[Marty_G]

5 hours ago, Frankie4Fingers said:

I have a Munich Helles that is just starting to move now having pitched 2 x SafLager W-34/70 into it on Sunday.  The SV is on and I plan to let the pressure rise up to ~ 10PSI but I am keeping the temperature at about 12.5C initially.  I will then increase the temp when it gets to around 10 points from FG to perform a diacetyl rest.

The reason for using pressure is that you can use higher temps. So with lagers the lagering is weeks not months. Fermentation is quicker at the higher temps and there is no need for a D rest. The pressure suppresses the formation of phenol, diacytl and esters so with lagers in particular the profile is very clean. I ferment using W34/70 and Urquell 2001 and ferment at 24c and 15psi. Takes about a week from grain to keg.  3-4 days ferment, couple of days cold crash and then transfer to keg. Can then drink but I usually leave for a few weeks.  Ales is much the same but they are drinkable immediately in the keg and for those I use Kveik at 38c and 15psi. 

[Pezzza]

On 8/16/2020 at 2:53 PM, PaddyBrew2 said:

Really good tip cos I was stumped on how to clean them other than snipping the ends off , removing the fittings and washing. Which means losing cm's of line each time 

Only done it once... but just have liquid disconnects at either end of my liquid transfer line... and then just plug in that fitting Shamus @Shamus O'Sean has on end of his pump line see below.... and then push cleaning then sterilising solution through followed by some gas to blow it out? 

I guess if you haven't got any spare kegs that might be a problem - or have I missed something here?

 

[Pezzza]

7 hours ago, Frankie4Fingers said:

2 x SafLager W-34/70

W34/70 is a beautiful thing.... and seems to cope being a bit warmer - and especially if under pressure Frankie...  I am not sure why you would bother keeping it that cold... unless that is your ambient?  I warmed mine up a bit to get the yeast moving a bit faster and pressure I think was in the main around 12PSI.... came up very nice.   Only thing next time I would cold-crash before kegging... this time I/we were in a bit of a hurry ; )

[Frankie4Fingers]

21 minutes ago, Bearded Burbler said:

W34/70 is a beautiful thing.... and seems to cope being a bit warmer - and especially if under pressure Frankie...  I am not sure why you would bother keeping it that cold... unless that is your ambient?  I warmed mine up a bit to get the yeast moving a bit faster and pressure I think was in the main around 12PSI.... came up very nice.   Only thing next time I would cold-crash before kegging... this time I/we were in a bit of a hurry ; )

It's not the ambient, I can control that via my STC, heat belt and it's in a fridge as well.  I'm relatively new to pressure fermenting so not sure exactly what are the best options to go with and what the impact is for temp v psi v beer type.  Is there a simple article or guide on that?

What temp did you ferment the 34/70 out at? Anywhere near the 24c that Marty hits?

[Pezzza]

On 8/17/2020 at 10:15 PM, Frankie4Fingers said:

It's not the ambient, I can control that via my STC, heat belt and it's in a fridge as well.  I'm relatively new to pressure fermenting so not sure exactly what are the best options to go with and what the impact is for temp v psi v beer type.  Is there a simple article or guide on that?

What temp did you ferment the 34/70 out at? Anywhere near the 24c that Marty hits?

No simple guide.... as far as I am aware... other Brewers may know better.....

Just that pressure replicates cooler conditions re yeast population metabolism, dynamics and resultant metabolic outputs such as esters... so you can push the Lager Yeast along at higher temps but at pressure and still end up with a good result...

Pretty sure mine was at 18 degC and around that 12 PSI point.... and the brew was v good.

Next time will cold crash and then likely will be clearer.

[iBooz2]

On 8/16/2020 at 2:29 PM, Titan said:

one of the things that hacked me off about closed transfer was the cleaning of the transfer line. Here is a tip for cleaning that line. Kegland do a tee piece and plastic carb caps. You need 3 caps and a tee for around $15. Oh you also need a standard soda bottle and a small piece of line. Gas in right, Starsan out the top and your third cap goes to waist water. Only need a couple of psi to do this.

I simply use a couple of old 1.5 litre PET soft drink bottles with the red plastic screw on connectors from Kegland fitted to the top (you can buy them cheap in packs of 10).  You do not need a lot of pressure so just squeezing the PET bottle is good enough so save your CO2.  You simply have another one of those red connectors clipped into/at the opposite end of the line your are cleaning to allow any out flow.

Step 1. First bottle is full of warm water, clip it onto the transfer line (or any other line), squeeze the bottle until warm water flushes out the line.  Takes bugger all.

Step 2. Next bottle if full of PBW or similar, again squeeze that bottle to flush and fill the line with cleaner.  I generally leave the cleaner in there overnight.

Step 3. Use first bottle again with hotter water this time and squeeze it to flush the cleaner out of the line.

Step 4. Then use a bottle filled with sanitiser and squeeze it to push sanitiser through the line. Again usually leaving the sanitiser in the line/s for 30" or so or until ready for next use.

Step 5. Use empty sanitiser bottle from step 4 or any other pre-sanitised empty PET,  squeeze it to push air into and flush out the sanitiser from the line.  You could use you CO2 here but I prefer to save that for carbing up the kegs.

Cheers - AL

 

Edited August 19, 2020 by iBooz2

[Frankie4Fingers]

32 minutes ago, Bearded Burbler said:

No simple guide.... as far as I am aware... other Brewers may know better.....

Just that pressure replicates cooler conditions re yeast population metabolism, dynamics and resultant metabolic outputs such as esters... so you can push the Lager Yeast along at higher temps but at pressure and still end up with a good result...

Pretty sure mine was at 18 degC and around that 12 PSI point.... and the brew was v good.

Next time will cold crash and then likely will be clearer.

 

Ok thanks.  I have increased the temp up to 15C and left it at around 10 - 12 PSI.  I will ratchet it up tomorrow morning to 18C and see what the outcome is.  From where it started I will have gone from 12C > 15C and finally to 18C.  I will leave it at 18C until I CC and then see how the taste turns out.  I plan to sample at the point of kegging but then I will leave it in the keg fridge for a few weeks before putting on the gas.