Opening fermentation vessel

[Scampy]

This may sound very silly, but how safe is the fermenting beer in a fermentation bucket when the lid is temporarily opened?

I always thought that fermenting beer in the vessel was susceptible to bacteria in the air - hence the need for the lid and bubbling air lock filled with water.

Therefore can the fermenting beer be exposed to ruining bacteria when just opening the lid to take a gravity reading, or to give the liquid a stir with a sterile paddle, e.g. because the gravity has stalled ??

 

[QED]

If it's still fermenting then a quick open and close isn't going to cause much of an issue. Once it's closed again, the remainder of the fermentation should (hopefully) purge any oxygen that was let in.
Don't be opening it and leaving the lid wide open for an extended period and doing the dusting though.

 

[strange-steve]

Therefore can the fermenting beer be exposed to ruining bacteria when just opening the lid to take a gravity reading, or to give the liquid a stir with a sterile paddle

Yes it can but as long as it's brief then it's a small risk, fermented wort (beer) is a rather inhospitable environment for microbes due to the low pH and ethanol content.

 

[An Ankoù]

When you consider that most trad English fermentation was done in open vessels and some still is, then that sort of puts stuff into perspective. @terrym has had something to say about this in the past and my many many trips to Eldridge Pope's in Dorchester (RIP) backs that up. But, what I saw there was really thick and solid yeast heads- you could almost drive a tank over it! On our level. I would agree with @strange-steve, particularly towards the end of the fermentation.

 

[terrym]

As I understand it the 'traditional' way of brewing beer in the UK in large breweries was to use open squares, slate lined (Yorkshire) or copper. Marstons still use the Union system (originally from the Bass brewery?) which is also an open system. Enclosed systems have only come about in my lifetime as brewhouses have been revamped and modernised. But a trip round one of the old breweries will still find open fermenters in buildings constructed in the 19thC. If infections would have been commonplace in breweries using this brewing method it would have been abandoned years ago. And I suppose to back this up on a visit to the York brewery I asked the brewer if they ever had infections due to their open systems and I got a definite 'No' as an answer.
My view on 'keeping the lid on' on a homebrew FV is to keep it on as much as you can, but if your beer needs an intervention between pitching and packaging don't be afraid to look inside.

 

[wizurd1977]

Ive done it on my last two brews to add dry hops, not had a problem. Also the FV i use has a lid that doesn't really seal. The bubbler never bubbles so the gas must be getting out through the lid seal but again it's not caused any problems. I do have my FV in a brew fridge though, in case that makes a difference.

 

[Sadfield]

In my view the issue is when people are continually lifting then replacing the lid.

You can happily ferment totally open as long as there is off gassing of CO2. CO2 doesn't blanket the top of an open fv, it mixes with the environment around it, but the upward draft of the copious amounts CO2 provides protection. Once that vigorous off gassing slows, the fv gets covered or the beer racked to a closed vessel. I'd be highly surprised if any brewery ferments a beer out completely, open.

With a closed fv, once fermentation is underway then the head space contains nothing but CO2.

Opening the fv will mix that CO2 with air, every time you do it. The more you do it the greater the risk of contamination, particularly as the krausen drops.

 

[Madhouse]

Fine to open up the FV for that kind of thing, I do it when dry-hopping. Not so much for gravity readings now I've added a tap to the FV.

 

[the_quick]

As other say, all good to open for a short time.

The difference between us at home brewing and proper breweries with open fermentation is fermentation time. Most of the breweries will ferment for around 5 days and transfer it to casks for few weeks, where it will finish fermentation and naturally carbonate - that why they don't add sugar. We on other hand, leave our fermenters for 10-14 days, which allows it to fully ferment, add sugar to bottles (or force carb in kegs).

I don't use airlocks, my lids are not air tight - but never had a problem because of that - no contamination

 

[Scampy]

Thanks for your replies everyone. As I'm new to this wonderful hobby, i did wonder how the lid on a FV could be removed temporarily without introducing bacteria. Now i know!

 

[Victor Churchill]

I made a whoopsie error the other day when adding the hops to a Bulldog Hercule Saison. It had had 10 days in the FV, the SG was saying 1010 and I openetd the lid to add the hop tea , waited till the hoptea cooled ... and forgot about it till the next day! I'm gonna check it today and probably bottle today/tomorrow ... will let you know what transpires (where's the emoji for fingers-crossed?)

 

[ARNWD]

Hi,

As a new member I doubt I can post links but for a Youtube video of open fermentation search Youtube for:-

Timothy Taylor's - Fermentation Section

Timothy Taylor's has a set of brewery videos as well as a virtual brewery tour.

Cheers.

 

[HomeBrewer_UK]

I made a whoopsie error the other day when adding the hops to a Bulldog Hercule Saison. It had had 10 days in the FV, the SG was saying 1010 and I openetd the lid to add the hop tea , waited till the hoptea cooled ... and forgot about it till the next day! I'm gonna check it today and probably bottle today/tomorrow ... will let you know what transpires (where's the emoji for fingers-crossed?)

So, how did it go? All well i hope?

 

[Hanglow]

As other say, all good to open for a short time.

The difference between us at home brewing and proper breweries with open fermentation is fermentation time. Most of the breweries will ferment for around 5 days and transfer it to casks for few weeks, where it will finish fermentation and naturally carbonate - that why they don't add sugar. We on other hand, leave our fermenters for 10-14 days, which allows it to fully ferment, add sugar to bottles (or force carb in kegs).

I don't use airlocks, my lids are not air tight - but never had a problem because of that - no contamination

I remember reading the late Graham Wheeler going on a rant ( graham was great at ranting, i wish i'd saved them) on Jims about people leaving their beer too long in the primary fv, saying we should be getting it into the serving vessel as soon as possible. Since then I've steadily reduced the time in the fermentor, going as far to sometimes use forced ferment tests so i can bottle with residual extract. End result are beers that are better and I'd now never consider leaving a bitter longer than a week in the fermentor. Ideally it would be a bit less, but it's not always practical to do so

 

[foxy]

Get rid of the lid and cover with cling wrap, if you want to see whats going on look through the cling wrap. 3 to 4 days your fermentation is about done. Transfer to secondary if you are dry hopping, 3 days tops. Cold crash to -1 or 2 C ABV dependent 2 -3 days. Bottle, keg or cask, as long as every step from grain crush to end of fermentation has been adhered to then you will end up with a clear, tasty beer. No finings needed.

 

[gb0wers]

I remember reading the late Graham Wheeler going on a rant ( graham was great at ranting, i wish i'd saved them) on Jims about people leaving their beer too long in the primary fv, saying we should be getting it into the serving vessel as soon as possible. Since then I've steadily reduced the time in the fermentor, going as far to sometimes use forced ferment tests so i can bottle with residual extract. End result are beers that are better and I'd now never consider leaving a bitter longer than a week in the fermentor. Ideally it would be a bit less, but it's not always practical to do so

Interesting. This is something I'd not come across before. So, how much higher specific gravity do you bottle at, compared to the forced sample specific gravity please? Say the forced sample finished at 1.010, at what SG would you bottle the main batch?

 

[Fireside Ales Homebrewery]

When you consider that most trad English fermentation was done in open vessels and some still is, then that sort of puts stuff into perspective. @terrym has had something to say about this in the past and my many many trips to Eldridge Pope's in Dorchester (RIP) backs that up. But, what I saw there was really thick and solid yeast heads- you could almost drive a tank over it! On our level. I would agree with @strange-steve, particularly towards the end of the fermentation.

I have just got hold of a copy of Yeast by Chris White and Jamil Zainasheff. They have a section on open top fermentation and the benefits/ negatives of this method. Very interesting stuff. As you say though, the Krausen they describe sounds like concrete.
For the benefit of anyone interested and @Scampy ,here is a link to the copy of the book— Yeast: the practical guide to beer fermentation Download ( 286 Pages | Free )

 

[foxy]

I have put this up a few times, also Sierra Nevada aerate not oxigenate their beers.

 

[An Ankoù]

I have just got hold of a copy of Yeast by Chris White and Jamil Zainasheff. They have a section on open top fermentation and the benefits/ negatives of this method. Very interesting stuff. As you say though, the Krausen they describe sounds like concrete.View attachment 26931
For the benefit of anyone interested and @Scampy ,here is a link to the copy of the book— Yeast: the practical guide to beer fermentation Download ( 286 Pages | Free )

I've got a physical copy. It's very interesting as you say even if Chris White is a bit overoptimistic if he thinks we're all going to set up yeast labs and have a "clean" room to do our culturing in.

 

[terrym]

The difference between us at home brewing and proper breweries with open fermentation is fermentation time. Most of the breweries will ferment for around 5 days and transfer it to casks for few weeks, where it will finish fermentation and naturally carbonate - that why they don't add sugar.

I've seen videos where a small amount of sugar solution was added to a cask, and read about it here and there. Perhaps some breweries do and some don't.