Open FV, Anyone?

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... All makes perfect sense. The open FV idea was simply to see if - like the Bateman's open tanks (Yorkshire Squares) - it had any significant effect on the beer in a home-brew situation. I think I feel an experiment coming on here (and risk 5 gallons of beer asad1 ).

I have 2 remaining B&m real ale kits and 2 standard 25l fv buckets. Do I elect to make a side by side comparison test....
One closed lid and the other with a bit of net curtain strung across the top.
Not sure it would be a good test though, having only 11l in a 25l tall bucket, would the co2 dissipate enough sat in my utterly tranquil cellar on the open topped bucket?
 
Hi folks, I've done quite a bit of reading since starting this thread on the basis that a visit to our local brewery got me thinking. And after seeing their fermenters which were open-topped stainless steel bins. I'm going to start a side-by-side comparison test, I have two 5 gallon FV's now, and will split a bitter kit between them. One I will use an airlock as I normally do, and the other I'll just leave completely open - no cover, no muslin, just open. I (normally) use a top-fermenting yeast which may - or may not provide protection for the wort. I think general convection in the room will be enough to constantly purge CO2 and I'll have to rely a bit on sight, because I normally give an airlock three days to finish, so I'll have to rely on hydrometer readings on the open FV to check for a finished ferment.
 
Question: is fitting wire mesh (as in window screen) still considered open fermentation? Because it allows all wild yeasties and brethren in, but keeps fruitflies and jockstrapped Turkish wrestlers out.
 
Question: is fitting wire mesh (as in window screen) still considered open fermentation? Because it allows all wild yeasties and brethren in, but keeps fruitflies and jockstrapped Turkish wrestlers out.
See my #37 post.

I don't think so. CO2, as we all know, is heavier than air and will stagnate under a mesh barrier. Without the barrier weak air currents in the room get a chance to stir things up a bit. I suggested picturing what happened to dry-ice to get the idea (not entirely accurate because the CO2 so formed will be very cold and so even heavier than air - the cold condenses water vapour in the air so we see fog, the CO2 actually remains quite colourless).

(EDIT: The CO2 blanket isn't just keeping some things from possibly getting in, such as microbes and oxygen, its preventing things getting out too - more specifically CO2 - which could be responsible for driving the "open ferment" changes.)
 
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I quite like that article, cheers for digging it out.



But for everyone else please note the article also explains why "Sadfield" and I are not at each other's throats and use the words "I think" (or "I don't think") a lot. And are handing out conflicting advice. Do not take a polarised view, there is lots of very "ethereal" factors at work here. Neither "Sadfield" or I are wrong, but not conclusively right either.

The only facts that are guiding me is knowing I do not remember much special about the beer I used to produce in a bucket fermenter with a loose lid. And memories of TV programs illustrating the poisonings at Lake Nyos crater (mentioned in the article).

Experiment definitely, but don't then jump to conclusions and spout them out (unless you like starting pointless arguments).
 

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