Open fermentation experiment.

When you first start researching into homebrewing (if you research like I do) you may think that beer making is a delicate process, where the wind blowing east instead of west on brew day will ruin your beer. There are many more don'ts on brewing than do's. But in reality the beauty of homebrewing is the ability to push the envelope, toe the line and bend some rules a little. Like fermenting in an air tight container.


I am one of those people that can never take any word as absolute law when it comes to most anything. If you tell me the beer must sit in primary for 3 weeks before bottling and then another 3 weeks in bottle to condition, I'm going to ferment for 1 week and bottle for a few days just to see what I get. (surprisingly I'm a very patient person.)


Sometimes my rebellious nature works in my favor, sometimes it blows up in my face but it always gives me something interesting to bore my nonbrewing friends and family with. So that's a win in my book. And yes, I have successfully went grain to glass in less than 2 weeks with bottle conditioning. And yes, they were slightly better with an extra week on top of that.


I figured that in the past it was very unlikely that brewers had air tight fermenters. Long story short I decided to experiment a bit, and not put my the lid on my fermenting bucket. Of course I did my own research to see if it's already been done and found that I'm far from a trend setter. Either way, this should be fun.


Of course, open fermentation is nothing new. It's been done for ages, and even still done by some today. It also still holds a stigma among homebrewers as one of the many "don'ts" of brewing. I want to test that stigma, and see what my results are.


Here's a picture 12 hours after pitching, in a completely open fermenter. I know, some men just want to watch the world burn.

View attachment 1449293350778.jpg

Sub'd for update...I love these threads.

A Yorkshire stingo is still fermented in open stone fermentation vessels, this will be interesting to see how different the beer is compared to an airtight fermentation.

That's interesting, I wonder if the stone adds any flavor, possibly soaked in after many years of brewing. I imagine it could be difficult to properly sanitize depending on the texture of the stone and if it's polished smooth.

Anyways, onto a quick little update. Waking up this morning is 24 hours since yeast pitch. My room smells faintly bready and doughy.

I'm really enjoying this type of fermentation, because I can sit here and actually listen and watch it ferment. It sound kind of like rice crispies in milk. That crackling sound they make. It kinda makes me feel a little closer to this beer, if that makes any sense. It seems more alive, rather than just some bubbles in an airlock.

Temperature is at 69°f right now, which is about perfect. I was aiming for 68°f but part of my experiment is also the just put it in a stable and cool part of the house. So I'm not attempting any real temperature control, though I will step in if it gets over 70°f.

https://youtu.be/yY98NONjXbY Here's a short video of the fermentation. You can kinda hear the crackling, though it sounds more like static.

Sounds like you already know this is nothing new. Koelschips are a tried and true method to producing traditionally fermented beers. Pretty much every Trappist brewery practices open fermentation and top cropping without ill effect.

The reason homebrewers typically use closed-vessel fermentation is to avoid beer-tainting pathogens and otherwise undesirable contaminants. We don't pitch anywhere near as much yeast as commercial breweries, so the likelihood for cross-contamination and infection is much higher.

There is absolutely nothing wrong with this method, provided you're okay with a few fruit flies finding their way into your beer.

BrewingTravisty said:

I'm really enjoying this type of fermentation, because I can sit here and actually listen and watch it ferment. It sound kind of like rice crispies in milk. That crackling sound they make. It kinda makes me feel a little closer to this beer, if that makes any sense. It seems more alive, rather than just some bubbles in an airlock.

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That's awesome, nothing wrong with that! I've never left it completely open before, but I have just covered the top with muslin before so nothing large could get in. I have done that a few times with good results. There is some research to say that yeast prefers the non-pressurized environment. Too lazy to dig it up though

I done a few semi-open, piece of glass or cloth, fermentations lately they all turned out fine.

lowtones84 said:

That's awesome, nothing wrong with that! I've never left it completely open before, but I have just covered the top with muslin before so nothing large could get in. I have done that a few times with good results. There is some research to say that yeast prefers the non-pressurized environment. Too lazy to dig it up though

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The head of pressure formed over a yeast cake in a closed homebrewing fermenter is negligible, on the order of inches of water (airlock adds about 0.5 in. w.g. onto the existing 15-20 in. w.g.). However, in a commercial brewery with tall conicals, the head of pressure above the yeast cake will reach 150-200 in. w.g., which does accelerate yeast autolysis.

Found an interesting open fermentation brewery schematic, for those of you who are interested in commercial production of open-fermented beer:

specharka said:

The head of pressure formed over a yeast cake in a closed homebrewing fermenter is negligible, on the order of inches of water (airlock adds about 0.5 in. w.g. onto the existing 15-20 in. w.g.). However, in a commercial brewery with tall conicals, the head of pressure above the yeast cake will reach 150-200 in. w.g., which does accelerate yeast autolysis.

Found an interesting open fermentation brewery schematic, for those of you who are interested in commercial production of open-fermented beer:

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That's a really awesome schematic. I have eventual plans to open a brew pub, maybe if I have room I'll have an open fermenter.

lowtones84 said:

That's awesome, nothing wrong with that! I've never left it completely open before, but I have just covered the top with muslin before so nothing large could get in. I have done that a few times with good results. There is some research to say that yeast prefers the non-pressurized environment. Too lazy to dig it up though

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There's nothing where I have it that's large enough to bother with a muslin bag or anything. Maybe some airborne dust but that shouldn't hurt, and with the cold weather no bugs so I figured completely open would be fine. I wouldn't do it in the summer around here though haha I'd end up with everything from ants to wasps to scorpions in my beer.

specharka said:

Sounds like you already know this is nothing new. Koelschips are a tried and true method to producing traditionally fermented beers. Pretty much every Trappist brewery practices open fermentation and top cropping without ill effect.

The reason homebrewers typically use closed-vessel fermentation is to avoid beer-tainting pathogens and otherwise undesirable contaminants. We don't pitch anywhere near as much yeast as commercial breweries, so the likelihood for cross-contamination and infection is much higher.

There is absolutely nothing wrong with this method, provided you're okay with a few fruit flies finding their way into your beer.

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No need to worry about fruit flies, bugs are all sleeping this time of year haha I also pitched extra yeast in attempt to combat any wild things that decided to get in. Hopefully it works, if not then I'll just call it a Flanders red. No one drinking it will know the difference. Of course they probably won't go back for seconds either

I toured a brewery in Germany that was set up almost exactly like that schematic, with open concrete fermentors. Good beer, too. They had huge stainless vats of yeast (probably skimmed/dumped from previous batches) that they pitch into fresh wort. Lots of pictures here if anyone cares.

I would not recommend homebrewers do this unless you like to roll the dice every time you brew. If you can assure a raging fermentation immediately after the wort cools, great, but if not then you are going to end up with some ruined batches. I know that I can set a bowl of wort outside and have the surface laced with lacto or some other wild microbe a few days later.

BTW, if you look at these fermentors, they have a gorgeous krausen on that beer. That probalby helps protect it from infection and oxidation.

passedpawn said:

I toured a brewery in Germany that was set up almost exactly like that schematic, with open concrete fermentors. Good beer, too. They had huge stainless vats of yeast (probably skimmed/dumped from previous batches) that they pitch into fresh wort. Lots of pictures here if anyone cares.

I would not recommend homebrewers do this unless you like to roll the dice every time you brew. If you can assure a raging fermentation immediately after the wort cools, great, but if not then you are going to end up with some ruined batches. I know that I can set a bowl of wort outside and have the surface laced with lacto or some other wild microbe a few days later.

BTW, if you look at these fermentors, they have a gorgeous krausen on that beer. That probalby helps protect it from infection and oxidation.

http://www.youtube.com/watch?v=gwSazxo63DU

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I pitched enough yeast for fermentation to begin within a few hours, which I would imagine is key. You wouldn't want this to sit open to the air for 24 hours without the yeast taking off.

And yes, the krausen plus the blanket of c02 that will cover the wort will protect it fairly well.

From what I understand, you do get a slight oxidation when brewing open fermentation. That adds to the flavor profile from fermenting this way. You will get more esters this way as well, but I've heard they're softer than say esters from high temperature. This of course is all from what I've read, since this is my first time doing this. I've heard it works great for any kind of weizen, it will really enhance those fruity/banana flavors. I wouldn't say you would want to do this with every style, British styles would probably be a great candidate along with weizens and belgian ales.

All in all, this is just a for ****s and giggles, personal experiment to see what happens. I chose to do my red ale because 1) I had the ingredients on hand and 2) I thought it might be good, even if it soured. It is definitely a risk to brew like this, but that's part of the fun for me.

BrewingTravisty said:

I pitched enough yeast for fermentation to begin within a few hours, which I would imagine is key. You wouldn't want this to sit open to the air for 24 hours without the yeast taking off.

And yes, the krausen plus the blanket of c02 that will cover the wort will protect it fairly well.

From what I understand, you do get a slight oxidation when brewing open fermentation. That adds to the flavor profile from fermenting this way. You will get more esters this way as well, but I've heard they're softer than say esters from high temperature. This of course is all from what I've read, since this is my first time doing this. I've heard it works great for any kind of weizen, it will really enhance those fruity/banana flavors. I wouldn't say you would want to do this with every style, British styles would probably be a great candidate along with weizens and belgian ales.

All in all, this is just a for ****s and giggles, personal experiment to see what happens. I chose to do my red ale because 1) I had the ingredients on hand and 2) I thought it might be good, even if it soured. It is definitely a risk to brew like this, but that's part of the fun for me.

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Yea I get it, you're just screwing around and experimenting. My comments were just to make sure our noobs are clear on the risks. I was once a noob, and I can still remember how confusing everything was, and how many misunderstandings I had.

BTW, the CO2 blanket is a myth. If your bucket is open to the air, the CO2 will not sit in there once fermentation is done. It will quickly expand to fill the universe. It's the law of gases. The more dense it is, the more slowly it mixes, but it will leave that bucket pretty quickly.

passedpawn said:

Yea I get it, you're just screwing around and experimenting. My comments were just to make sure our noobs are clear on the risks. I was once a noob, and I can still remember how confusing everything was, and how many misunderstandings I had.

BTW, the CO2 blanket is a myth. If your bucket is open to the air, the CO2 will not sit in there once fermentation is done. It will quickly expand to fill the universe. It's the law of gases. The more dense it is, the more slowly it mixes, but it will leave that bucket pretty quickly.

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Oh ok, well that makes sense I guess. But I imagine, even with that, while it's fermenting it will still have that c02 blanket as it off gases. I was planning on putting the top on after fermentation finished for a few days before racking.

As far as making clear of the risks, I completely understand. Before doing stuff like this you should understand the basics and have your procedure down pat. This is definitely not a beginner procedure. Honestly, I probably will only attempt this with beers that it actually will work well with like Belgians and hefeweizens. But yes there definitely needs to be a disclaimer here lol you need to be ready to waste 5 gallons of beer when attempting anything like this.

Ok, day 2 and the krausen has dropped. Smells very bready, almost like a rye bread dough. The gravity is at 1.015 from 1.050 so I'm hoping it will get a few more points shaved off by tomorrow. I'm aiming for about 1.011.

Now that the krausen has dropped I went ahead and put the lid back on, since it doesn't have that protection from the krausen anymore.

I'll update with tasting notes tomorrow.

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I would make the suggestion to package this as soon as possible. Even with putting the lid on now, once that krausen drops, anything in that headspace is going to start working it's way into the beer. If it were me, I probably would've sprayed a little starsan onto the top and the sides. If you've sealed it, it should continue to fill up with co2, but it still might not be fast enough to give those microbes enough oxygen to get going.

Again, just further disclaimer for the noob reading this.

And no, even with constant off-gassing, there still won't be much of a co2 blanket. Gases mix incredibly quickly. co2 is not as dense as people think it is. Here is a video showing how bromine mixes with air in a trapped space with no air movement to encourage the mixing. Bromine has a density of 7.14 g/l at STP, while co2 has a density of 1.97 g/l at STP, while no2 is 2.05 g/l at STP. And you see how much faster no2 diffuses than bromine in the video. Add any kind of air movement, which will also be happening simply because of the movement of the fermentation and the off-gassing, and the co2 will diffuse rather quickly, creating practically no blanket at all.

joshesmusica said:

I would make the suggestion to package this as soon as possible. Even with putting the lid on now, once that krausen drops, anything in that headspace is going to start working it's way into the beer. If it were me, I probably would've sprayed a little starsan onto the top and the sides. If you've sealed it, it should continue to fill up with co2, but it still might not be fast enough to give those microbes enough oxygen to get going.

Again, just further disclaimer for the noob reading this.

And no, even with constant off-gassing, there still won't be much of a co2 blanket. Gases mix incredibly quickly. co2 is not as dense as people think it is. Here is a video showing how bromine mixes with air in a trapped space with no air movement to encourage the mixing. Bromine has a density of 7.14 g/l at STP, while co2 has a density of 1.97 g/l at STP, while no2 is 2.05 g/l at STP. And you see how much faster no2 diffuses than bromine in the video. Add any kind of air movement, which will also be happening simply because of the movement of the fermentation and the off-gassing, and the co2 will diffuse rather quickly, creating practically no blanket at all.

https://www.youtube.com/watch?v=_oLPBnhOCjM

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That's really useful information thanks! And yeah I plan on bottling this tomorrow or Tuesday. It will be drank fairly quickly too, I'll have some help with that part lol

And yes, major disclaimer to anyone new to brewing. Don't do this, unless you're willing to waste a batch and even then make sure your sanitation practices are on point. I'm brewing this with the mind that if it goes wrong, it's all in the spirit of experimenting. Also to anyone new to brewing, don't forget that if you get an infection in a plastic container and rack with a plastic siphon/tubing you'll want to replace everything. So do as I say not as I do xP

joshesmusica said:

I would make the suggestion to package this as soon as possible. Even with putting the lid on now, once that krausen drops, anything in that headspace is going to start working it's way into the beer. If it were me, I probably would've sprayed a little starsan onto the top and the sides. If you've sealed it, it should continue to fill up with co2, but it still might not be fast enough to give those microbes enough oxygen to get going.

Again, just further disclaimer for the noob reading this.

And no, even with constant off-gassing, there still won't be much of a co2 blanket. Gases mix incredibly quickly. co2 is not as dense as people think it is. Here is a video showing how bromine mixes with air in a trapped space with no air movement to encourage the mixing. Bromine has a density of 7.14 g/l at STP, while co2 has a density of 1.97 g/l at STP, while no2 is 2.05 g/l at STP. And you see how much faster no2 diffuses than bromine in the video. Add any kind of air movement, which will also be happening simply because of the movement of the fermentation and the off-gassing, and the co2 will diffuse rather quickly, creating practically no blanket at all.

https://www.youtube.com/watch?v=_oLPBnhOCjM

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I think it's a good assumption for when there aren't temperature gradients driving convection loops to carry the gas away, i.e. a closed container. I've used a CO2 purge to deprive oxygen from a souring kettle and it seemed to work well.

In this case, I definitely agree with that assessment. I would be more worried about oxidation than anything else, personally. I've accidentally open-fermented when my lid blew off the fermenter and the beer tasted like wet cardboard after only a few hours' exposure.

specharka said:

I think it's a good assumption for when there aren't temperature gradients driving convection loops to carry the gas away, i.e. a closed container. I've used a CO2 purge to deprive oxygen from a souring kettle and it seemed to work well.

In this case, I definitely agree with that assessment. I would be more worried about oxidation than anything else, personally. I've accidentally open-fermented when my lid blew off the fermenter and the beer tasted like wet cardboard after only a few hours' exposure.

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Yeah, I only meant in an open container. In a completely closed system, with purging, one user, doug something or other, has proven that the o2 left after, i believe it was, 5 times of purging was nearly negligible.

But, I agree, I would be more concerned with oxidation. The thing I believe you mentioned, the cool ship (in english), actually tends to make a hard krausen that sticks around even after fermentation has finished. I'm not sure what causes that (it's usually lagers made in those cool ships, so it could have something to do with the temperature), but it seems that gives the protection needed until packaging. In this case, his krausen dropped, and I don't doubt he will get a bit of oxidation, although, since he covered it fairly quickly after the krausen dropped, he could possibly be ok on the infection and oxidation fronts.

BrewingTravisty said:

When you first start researching into homebrewing (if you research like I do) you may think that beer making is a delicate process, where the wind blowing east instead of west on brew day will ruin your beer. There are many more don'ts on brewing than do's. But in reality the beauty of homebrewing is the ability to push the envelope, toe the line and bend some rules a little. Like fermenting in an air tight container.


I am one of those people that can never take any word as absolute law when it comes to most anything. If you tell me the beer must sit in primary for 3 weeks before bottling and then another 3 weeks in bottle to condition, I'm going to ferment for 1 week and bottle for a few days just to see what I get. (surprisingly I'm a very patient person.)


Sometimes my rebellious nature works in my favor, sometimes it blows up in my face but it always gives me something interesting to bore my nonbrewing friends and family with. So that's a win in my book. And yes, I have successfully went grain to glass in less than 2 weeks with bottle conditioning. And yes, they were slightly better with an extra week on top of that.


I figured that in the past it was very unlikely that brewers had air tight fermenters. Long story short I decided to experiment a bit, and not put my the lid on my fermenting bucket. Of course I did my own research to see if it's already been done and found that I'm far from a trend setter. Either way, this should be fun.


Of course, open fermentation is nothing new. It's been done for ages, and even still done by some today. It also still holds a stigma among homebrewers as one of the many "don'ts" of brewing. I want to test that stigma, and see what my results are.


Here's a picture 12 hours after pitching, in a completely open fermenter. I know, some men just want to watch the world burn.

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Interesting... During your experiment did you skim the top with a sanitized spoon on a regular basis or just let it drop to the bottom of the bucket?

Breweries who practice open fermentation rack the beer to cask or bright tank before the krausen drops, as the fermentation is either near complete or complete, so that protects the beer. Also you have much more surface area to beer there compared to breweries open fermentation tanks - they tend to be about 6 feet deep. So if you want the yeast to behave in a similar fashion, then it might be best to construct a fermentor out of a thick pipe - in fact the NCYC has fermentors just like this to mimic commercial ones and so the yeast behaves more accurately

I always open ferment in buckets, but I always keep the lid on, just not on tight so there is no pressure even from an airlock. There's no benefit to having it completely open, only negatives

AF1HomeBrew said:

Interesting... During your experiment did you skim the top with a sanitized spoon on a regular basis or just let it drop to the bottom of the bucket?

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I just let it drop, in hind sight I probably should have skimmed to minimize the amount of undesirables that would be on top of the krausen.

joshesmusica said:

Yeah, I only meant in an open container. In a completely closed system, with purging, one user, doug something or other, has proven that the o2 left after, i believe it was, 5 times of purging was nearly negligible.

But, I agree, I would be more concerned with oxidation. The thing I believe you mentioned, the cool ship (in english), actually tends to make a hard krausen that sticks around even after fermentation has finished. I'm not sure what causes that (it's usually lagers made in those cool ships, so it could have something to do with the temperature), but it seems that gives the protection needed until packaging. In this case, his krausen dropped, and I don't doubt he will get a bit of oxidation, although, since he covered it fairly quickly after the krausen dropped, he could possibly be ok on the infection and oxidation fronts.

Click to expand...

I was actually half expecting the krausen to harden and not drop, from the way it was looking last night. It was dropped when I woke up this morning, so it may have had a few hours with no protection. I'll probably taste it later to see how it is, but I see no signs pointing towards oxidation or infection at the moment.

Also, during the more vigorous parts of fermentation the yeast will consume any oxygen that is in the liquid. Its very nearly impossible to oxidize your beer while fermenting. Most oxidization will come from racking to secondary or bottling/kegging. Or, some may say from hotside aeration. Personally I've never seen anything to suggest that that is a concern on the homebrew level.

Hanglow said:

Breweries who practice open fermentation rack the beer to cask or bright tank before the krausen drops, as the fermentation is either near complete or complete, so that protects the beer. Also you have much more surface area to beer there compared to breweries open fermentation tanks - they tend to be about 6 feet deep. So if you want the yeast to behave in a similar fashion, then it might be best to construct a fermentor out of a thick pipe - in fact the NCYC has fermentors just like this to mimic commercial ones and so the yeast behaves more accurately

I always open ferment in buckets, but I always keep the lid on, just not on tight so there is no pressure even from an airlock. There's no benefit to having it completely open, only negatives

Click to expand...

Actually if you watch the brewingtv episode on open fermentation, you'll see that the person they talk to about it actually is using a large metal tub, to maximize the surface area in contact with the air. Though he does rack from underneath the krausen. I had planned to do the same, not expecting the krausen to fall in less than 36 hours.

Going into the next open fermentations in the future, I'll probably cover loosely with the lid just to be on the safe side.

Hanglow said:

Breweries who practice open fermentation rack the beer to cask or bright tank before the krausen drops, as the fermentation is either near complete or complete, so that protects the beer. Also you have much more surface area to beer there compared to breweries open fermentation tanks - they tend to be about 6 feet deep. So if you want the yeast to behave in a similar fashion, then it might be best to construct a fermentor out of a thick pipe - in fact the NCYC has fermentors just like this to mimic commercial ones and so the yeast behaves more accurately

I always open ferment in buckets, but I always keep the lid on, just not on tight so there is no pressure even from an airlock. There's no benefit to having it completely open, only negatives

Click to expand...

Well that's just not true at all...


Brasserie Cantillon, Brussels Belgium


Allagash, Portland ME

Those are coolships, for cooling, they are supposed to be big and wide. They don't ferment in them - although of course they pick up the yeast there so I guess there is a small amount

I just took a sample for tasting, and it took me by surprise. It's slightly tart, but not like it's soured. It just has a slight fruity tang to it, the marris otter comes through with a nice bready biscuity hint, and the rye is there but more subdued than normal. The fruity esters really take front stage with a nice kind of apricot flavor, followed by the malts and a slight rye bite at the end. The Galena hops don't seem to come through at all, which is appropriate. All in all its a well balanced, apricot rye ale. I'll cold crash and bottle it, aiming for about 2.5 volumes of c02. I would definitely say I will be doing this again.

Original recipe: Red Rye Ale
Final product: Apricot Rye Ale
OG: 1.050
FG: 1.012

Final notes: I may attempt this same recipe but purposefully sour it. I believe this would make a wonderful soured rye, especially if I could keep those apricot notes.

Next week I'll be doing a hefeweizen open fermentation as well, though I'll pay closer attention and try to rack before the krausen drops. I'll update again with tasting notes in a week or 2 once this is carbed


Edit: Disclaimer: If you decide to do this style of fermenting, do more research and don't do it the way I did. Just because mine turn out good this time, that doesn't mean it always will. Any time you try one of the more risky procedures when brewing, always be ready to have a ruined batch that you need to throw away.
That said, this is a very viable way to ferment if done right and can lead to some surprising and very interesting changes in your recipes. I would only recommend doing this with styles that you want the fruity esters in.

Hanglow said:

Those are coolships, for cooling, they are supposed to be big and wide. They don't ferment in them - although of course they pick up the yeast there so I guess there is a small amount

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What do you think they use the koelschip for? Pitch and batting practice?

specharka said:

What do you think they use the koelschip for? Pitch and batting practice?

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eh? Clue's in the name.

They ferment at cantillon in barrels.

BrewingTravisty said:

I just let it drop, in hind sight I probably should have skimmed to minimize the amount of undesirables that would be on top of the krausen..

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The reason I asked was a fellow brewing buddy tried open fermentations and used a sanitized spoon for the first day or two before transferring it to a closed fermenter. The Hefeweizen that he made using this method was amazing.

He had an open fermenter just like the one I have in the attached photos. Another brew club member made these for us. He was practicing his welding skills. I haven't gotten around to using it though. The lid overlaps the sides...

Hanglow said:

eh? Clue's in the name.

They ferment at cantillon in barrels.

Click to expand...

Sorry, bad examples. Better ones:


Anchor Steam


Schnieder Weisse


Liefmans

The point is that a there are a lot of large, shallow open fermenters to maximize transmission of heat to ambient and practice top cropping.

I've seen plenty of open vessels here in the UK. Tall, relatively thin conical type vessels with open tops. Used for typical beers like bitters and the like and not to pick up any wild yeast.

Hanglow said:

eh? Clue's in the name.

They ferment at cantillon in barrels.

Click to expand...

specharka said:

Sorry, bad examples. Better ones:

Anchor Steam

Schnieder Weisse

Liefmans

The point is that a there are a lot of large, shallow open fermenters to maximize transmission of heat to ambient and practice top cropping.

Click to expand...

JKaranka said:

I've seen plenty of open vessels here in the UK. Tall, relatively thin conical type vessels with open tops. Used for typical beers like bitters and the like and not to pick up any wild yeast.

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I imagine that there are different fermentation tanks for different styles to minimize or maximize the bugs.

AF1HomeBrew said:

The reason I asked was a fellow brewing buddy tried open fermentations and used a sanitized spoon for the first day or two before transferring it to a closed fermenter. The Hefeweizen that he made using this method was amazing.

He had an open fermenter just like the one I have in the attached photos. Another brew club member made these for us. He was practicing his welding skills. I haven't gotten around to using it though. The lid overlaps the sides...

Click to expand...

I would love to have something like that! And yeah I'm planning on doing this again with a hefeweizen, I've heard it works really well with that style. It's also my favorite style of beer, so I love the thought of going as authentic as you possibly can without ordering water from Germany xD

He mentioned that he was using an english yeast, (although it was so4 which is ironically a yeast developed in/for cylindro conicals ) so I thought to mention the depth. Most aren't quite as shallow as those you just linked, although they are still shallow compared to modern cylindro conicals. A six foot fermenter would allow 4 feet of beer enough space for the yeast.

Hanglow said:

He mentioned that he was using an english yeast, so I thought to mention the depth. Most aren't quite as shallow as those you just linked, although they are still shallow compared to modern cylindro conicals

Although it was so4 which is ironically a yeast developed in/for cylindro conicals

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Oh really? I didn't know that! It would be neat to get fermenters meant for open fermentation like that, and some shallow ones too.

Yeah it would make a good experiment to see how different yeasts behave in a standard bucket/carboy and a taller fermenter. Just split the batch and compare with a triangle test once they've finished fermenting

Sounds like too much hard work for me

Hanglow said:

Yeah it would make a good experiment to see how different yeasts behave in a standard bucket/carboy and a taller fermenter. Just split the batch and compare with a triangle test once they've finished fermenting

Sounds like too much hard work for me

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Sounds like something that would be right up my alley, if I ever got my hands on a taller fermenter, and maybe a shallow one too. Do a three way experiment. Brew up about 10 gallons and split it between the three. I love trying different things though, keeps things interesting haha have the control brew in a closed bucket, and the other 2 in different types of open fermenters. Maybe one day.

It would be good if one was to repitch the yeast for a few generations to see if they adapt differently as well. I don't know if the difference in pressure between say 2ft of wort and 4ft would make much difference?

I was thinking of getting something like in the open fermentation episode of brewing tv when I finally get to set up a dedicated room just for fermenting. Basically like a stainless steel sink for washing and cleaning fish you caught. A 5 gallon batch would be less than a foot deep. And then maybe have a friend weld up a deep and slim container for the other one. I could run an extended experiment in whichever I preferred for the yeast, to see how they evolve and use just that one recipe with the yeast. I wonder if the flavor would evolve much. I imagine the yeast might just get stronger against unwanted yeasts and other bugs.

I guess my question would be, if you are fermenting via open container, then follow up by taking all the conventional precautions found in a closed-container ferm (those that normally preclude oxidation, contamination, off-flavors, etc.), then why the open ferm to begin with?

IOW, all else being equal, what does an open container ferm to do benefit the beer?

GHBWNY said:

I guess my question would be, if you are fermenting via open container, then follow up by taking all the conventional precautions found in a closed-container ferm (those that normally preclude oxidation, contamination, off-flavors, etc.), then why the open ferm to begin with?

IOW, all else being equal, what does an open container ferm to do benefit the beer?

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I've read about some British yeasts not liking the pressure of a closed vessel. A clear benefit I can see is that, if there was no effect on the beer, the open vessel would be cheaper to obtain and maintain.