Open fermenting Hefeweizen?

[arnobg]

Does anyone do it regularly for their hefeweizens? I was considering giving this a try for the first time, what things do I need to keep in mind?

I would do it in a bucket inside a chest freezer for temperature control.

 

[GHBWNY]

Just curious as to the theory behind leaving the lid off your fermenter for a small-batch hefe (or any beer). I know there is a tradition of doing this for a wheat beer. Some believe it leaves more opportunity for the yeast to work ??? = more yeast taste ???, or provides the option of skimming off the krausen (which settles out of suspension like every other beer). My hefes have taken up to almost 2 weeks for high krausen to drop, and I'm not sure I would advise leaving a fermenter open that long (or at all). The krausen can act like an open-air sponge that can easily snatch airborne critters floating by. I could see possibly doing this 200 years ago in a large, 100 gal. open vat where a lid may have been impractical, but for a 5 gal batch does it make a measurable difference when weighed against the possibility of inviting nasties into your brew? Your call. Hope it works.

 

[ThatVideoKid]

Just curious as to the theory behind leaving the lid off your fermenter for a hefe (or any other beer)?

I know the reasoning behind it with the tricky saison strains, they say that the head pressure it actually what is causing the yeast to give up too early.

I'm not sure with a hefe, but that is how many of the German Brewers do it so it must be for a reason

 

[LLBeanJ]

I do this. I use a bucket fermenter and cover it loosely with a piece of foil instead of a lid. I've had problems with excessive sulfur in the past with my hefeweizens and doing this solved it.

 

[arnobg]

There's a bunch of discussion of it on the forums as well as side by side comparisons if you're interested in the "why". Check out YouTube and a Google search as well.

https://byo.com/mead/item/1211-open-fermentation-tips-from-the-pros


https://youtu.be/X9xT8DHOZFE


The side by side comparisons have proven large differences in character.

 

[arnobg]

I do this. I use a bucket fermenter and cover it loosely with a piece of foil instead of a lid. I've had problems with excessive sulfur in the past with my hefeweizens and doing this solved it.

I am curious about your method, but what difference is foil over the top from a lid that isn't air tight and may have a leaky seal? Seems to me this isn't really open fermentation, but I don't know?

 

[GHBWNY]

I do this. I use a bucket fermenter and cover it loosely with a piece of foil instead of a lid. I've had problems with excessive sulfur in the past with my hefeweizens and doing this solved it.

I think most hefes traditionally ferm out with a noticable eggy smell, but it normally goes away.

 

[LLBeanJ]

I am curious about your method, but what difference is foil over the top from a lid that isn't air right and may have a leaky seal? Seems to me this isn't really open fermentation, but I don't know?

Best I can figure is that a lid just sitting on top of the bucket, not snapped on, still created too much head pressure which would not allow the sulfur to escape, whereas a piece of foil draped over the top didn't have that problem. After two batches that had persistent sulfur issues, I switched to the "foil lid" and had no sulfur issues.

 

[arnobg]

Best I can figure is that a lid just sitting on top of the bucket, not snapped on, still created too much head pressure which would not allow the sulfur to escape, whereas a piece of foil draped over the top didn't have that problem. After two batches that had persistent sulfur issues, I switched to the "foil lid" and had no sulfur issues.

Do you put a lid on after a certain amount of time when fermentation has slowed to reduce risk of oxygen exposure or infection?

 

[LLBeanJ]

I think most hefes traditionally ferm out with a noticable eggy smell, but it normally goes away.

Normally, yes. But after nearly three weeks in the fermenter and still having a very strong sulfur taste/smell present in the beer, I had to try something different, hence the foil top, which I decided to try after reading some posts from other brewers who had similar sulfur problems.

I brewed two back to back sulfur bomb hefe's (one with 3068 and the other with WLP351) where the sulfur taste in the beer never cleared up on its own. I threw in the towel on the first one after two months at room temp in a keg with no improvement and racked it back into a fermenter on 6 lbs of blueberries and a fresh pitch of yeast. Was able to salvage the brew that way. The other one is still in a keg and will get the same treatment, but with strawberries, one of these days when I get around to it.

 

[tagz]

I've done this quite a few times with 3724, hoping that it would help get past the 1.030 stall. While I had no problems with the technique, I found that temp profile and yeast generation had a larger impact.

On a large scale, pressure can reduce ester formation, so hefe brewers might use open fermentation to influence their flavor profile. However, their isn't a ton of pressure difference on a 5 gallon scale between an open and airlock ferment. I'd buy into the idea that it would help with the sulfur issue, but otherwise I would look toward mash rests, fermentation temps or even fermenter geometry to influence your profile. There was an interesting thread from an avid hefe brewer a while back. She tried out large rectangular Tupperware containers and claimed to notice a difference.

Anyway, report back!