What does open fermentation do to the beer?

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Well-Known Member
Jun 15, 2013
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hey guys,

I've been trying to read up on open fermentation and get some more information on it. I read that it is quite beneficial for the yeast in wheat beers to do an open fermentaiton. I have a wit fermenting that I left the lid open on my bucket during primary fermentation and only had a sheet of cheese cloth over it to prevent dust and insects to land in my beer ... the smell was just heavenly :D so I think the beer will taste great.

My question thou:

What is actually happening during the open fermentaiton? is the yeast more active due to the lowered pressure and added oxygen contact? Or is it less active since I had to rouse it up twice? The only thing I came accross on the web really just said and I am paraphrasing

"Open fermentation good makes beer taste mmmmmhmmm"

I don't know if there are any scientific journals out there that you guys could refer me to to get a more scientific explanation on the mmmmhmm part and how it becomes mmmhmm.

Thanks in advance
Cheers :mug: