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Real brewery technique vs mine - no air lock?

So I visited a local brew pub and saw what looked like an active fermentation that wasn’t air locked.

What’s your take on that?

Open fermentation has been around for eons. A lot of sours are brewed that way with the natural yeast on the air. Belgian is one country that still continues to do open fermentation


Open fermentation can also be used if you pitch a healthy, abundant amount of yeast.

As @damian_winter said these are often for sour beers.

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Was this fermenter in a closed room. I think breweries that use open fermentation have the air filtered to prevent contamination. I believe Sierra Nevada does this.

Actually, SN uses a positive pressure room for their open fermentations.

Thanks Denny. I understand what a positive pressure room is. Basically a fancy term for sealed. What i don’t get is how does the O2 enter the room. Obviously the pressure from CO2 produced is vented out and nothing allowed in.

A coolship is a process use by a brewery in my town. The brew mostly Belgian and sour style

IIRC from beer camp, they pump O2 into the room. That’s how the positive pressure is achieved.

good info; thanks guys!

Here’s a pic of hefeweizen fermenting at Sierra Nevada. They use the same system for the barleywine, too.

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Anchor ferments in open fermenters, too. I couldn’t get a good picture when i took the tour, alas.

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