• Welcome to National Homebrew Club Ireland. Please login or sign up.
October 23, 2021, 06:39:30 PM

News:

Want to Join up ? Simply follow the instructions here
Not a forum user? Now you can join the discussion on Discord


Talk to me about FVs - temp control vs pressure

Started by colm89, November 24, 2020, 03:39:32 PM

Previous topic - Next topic

colm89

While I mess about with making a sub par BIAB vessel, I'm more keen to buy a mostly off the shelf solution for fermentation.

Currently fermenting with 5 litre glass carboys in the bottom of a wardrobe in the spare bedroom, and want to upgrade to something that'll hold 20 to 30 litres.

I've been flipping between the fermentasaurus snub nose and brew monk ss conical with cooling coil.

Obviously the latter is almost three times the price of the snub nose, but what is more useful: The ability to maintain a stable temperature (with a submersible pump in a bucket of iced water, brew belt, and inkbird); or the ability to ferment under pressure?

I don't have the space for a dedicated fermentation fridge just yet and the grainfather glycol chiller is far beyond what I'm willing to spend. I won't be using a kegging system any time soon for a similar reason so not sure if pressure fermentation is right for me yet?

mick02

Quote from: colm89 on November 24, 2020, 03:39:32 PMWhile I mess about with making a sub par BIAB vessel, I'm more keen to buy a mostly off the shelf solution for fermentation.

Currently fermenting with 5 litre glass carboys in the bottom of a wardrobe in the spare bedroom, and want to upgrade to something that'll hold 20 to 30 litres.

I've been flipping between the fermentasaurus snub nose and brew monk ss conical with cooling coil.

Obviously the latter is almost three times the price of the snub nose, but what is more useful: The ability to maintain a stable temperature (with a submersible pump in a bucket of iced water, brew belt, and inkbird); or the ability to ferment under pressure?

I don't have the space for a dedicated fermentation fridge just yet and the grainfather glycol chiller is far beyond what I'm willing to spend. I won't be using a kegging system any time soon for a similar reason so not sure if pressure fermentation is right for me yet?
Hi Colm,

I've actually got a temp controlled fermentation fridge, a SS Chronical and a Fermzilla. I've only used the Fermzilla twice but here are some advantages that I find over the SS. First of all fermenting under pressure means that you can reduce the ester production in the yeast. This is particularly beneficial if you don't have temp control as the off flavours that yeast produce at higher temperatures will be less pronounced. I also like that I can cold crash my beer in the fermzilla and then either serve it directly from the fermenter (floating dip tube) or transfer it fully carbonated to a keg. The SS fermenter is good as it has a thermal well so I can get more precise control of the temperature in the process but it looks as though this is less of a consideration to you as you don't have temp control in the first place.

Now that I've moved to pressure fermentation I'm not sure I would go back. YMMV though. Good luck and let us know what you end up going with.

Mick
NHC President

TheSumOfAllBeers

Before you go spending craz-ey money on shiny kit, ensure you have proper temp control. You need the ability to put a ceiling on the fermentation temperature, and you need the ability to drop the temp to clear the beer.

Pressure fermentation helps with the former, but does nothing with the latter, unless you can move the keg somewhere really cold and north facing over the winter. Also if you are fermenting under pressure, then you need to transfer under pressure into either a serving keg, bottles (with pressure transfer kit - not really recommended) or serve out of the fermenting vessel (get cask widges or fermentasaurus float tube).

If you are really stuck for space, an external glycol chiller is not going to be a much smaller footprint than an undercounter fridge. Probably the best compromise might be 30L beer kegs with the spears removed and replaced with corny post adapters and cask widges. Ferment under pressure in the house, then transfer them outside to aid in settling. Then serve out of the keg itself. Also use yeasts that flocculate well.

phildo79

If you got a small pressure FV, you could possibly fit it inside an under the counter fridge. Once fermentation is over, just turn the fridge on and you basically have chilled kegged beer on tap (but without needing cornies, gas, regulator etc.). You'd probably want to drink the beer within a certain amount of time as I don't think leaving it on the yeast cake for ages is best practice.

FWIW, I have a snubnose and I love it. But my primary reason for getting it was to do closed transfers to corny kegs to avoid oxygen contact and prolong aroma and flavour. In that regard, it works a treat.

DEMPSEY

You say you don't have a fridge space :( . Temperature control is a vital part of fermentation so I would look to figuring out how to get some.
Dei miscendarum discipulus
Forgive us our Hangovers as we forgive those who hangover against us

Phil.cork

I use a brewpiless in an under counter fridge in the shed for temp control. There's a thread around here somewhere that's a how to. Can't recommend it strongly enough for cheap very accurate temp control

colm89

I've since bought one of those brewolution ferminators which has been fantastic, if a little fragile.


TheSumOfAllBeers

Thats not a bad product at all, if it lives up to the advertised specs. How is the beer working out for you?

colm89

Quote from: TheSumOfAllBeers on March 02, 2021, 09:49:33 PMThats not a bad product at all, if it lives up to the advertised specs. How is the beer working out for you?

Really good so far, first batch I made in the ferminator was a bohemian pilsner using the quick lagering method and it was excellent, possibly my best brew to date.

Pic above was taken of my first brew in the ss brew bucket with a blow off, where I foolishly set it to cold crash unaware of the risk of suck back and ended up having to pour the batch down the drain after it inhaled about a litre of starsan.

This of course has sent me down the rabbit hole of how to deal with cold crashing without pressure but that's for another day!

johnrm

To prevent suck back I guess the trick is to replace the blowoff with an airlock once fermentation has settled down.

nigel_c

I have the same SS brew bucket. When I cold crash i just pull the blow off and stick some tape over the hole. simple and works perfect.

TheSumOfAllBeers

If you take out the blow off tube and replace it with an airlock etc. you are going to suck back air - a lot of it, including plenty of O2 that you want to avoid.

Ideally you want to be able to add back sterile CO2, or capture some of the generated CO2 and reintroduce it during cold crashing. There are quite a few options to do that, and even more if you have access to CO2 (like with a kegging setup).

colm89

Yeah I think I'll just not bother with cold crashing until I have space for kegs!

johnrm

March 03, 2021, 11:45:50 PM #13 Last Edit: March 04, 2021, 07:25:29 AM by johnrm
Assuming you have some headspace you are going to have a co2 blanket on your beer.
Co2 out during fermentation is going to greatly voluminous compared to the small amount of air coming back in during cold crash.

TheSumOfAllBeers

well if the cold crash is strong enough to suck back 500 ml of starsan through a b/o tube, it will suck in more than that of air through an airlock.

That means 100ml of O2 minimum in your headspace. Your beer might tolerate it - though not an NEIPA - but there are cheap CO2 capture options that prevent it completely:

Edit: thought I could upload or share, but not so:
- a party baloon secured to the end of the blow off tube
- a water carrier - collapsible added to same