so your fermenting at ambient temperature??? and why scrape the kraussen layer off? has been mentioned that the layer on the top protects the work from oxygen in the air.
Open Fermentation
- Thread starter Ghostie
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so your fermenting at ambient temperature??? and why scrape the kraussen layer off? has been mentioned that the layer on the top protects the work from oxygen in the air.
Good article here by Jim Busch explaining open fermentation and the reason for skimming.
http://www.brewery.org/library/OpenFerm.html
http://www.brewery.org/library/OpenFerm.html
Mark, I have nothing but respect for the knowledge and passion for brewing excellent beer that you bring to this forum. I have been absent for a while now and was happy to see that you are still here championing good evidence-based practice. Furthermore I was hoping you could provide me with a 'recommended reading' list of quality research.
I do wonder, however, how much of the research that I presume applies to large-scale commercial breweries, translates to small-scale homebrewing. For example, beer staling due to oxidation. If a keg is consumed within a few weeks will this be an issue? Probably not. Not trying to excuse poor practice but I can't help but think that some research might be more relevant than others.
We have had discussions about this in the past and I have no illusions of changing your mind on this. Just raising the idea that, if the bulk of research is directed towards brewing large volumes that need to stay stable for relatively long periods of time, there may be a dearth of research applicable to homebrewing.
Happy to be proven wrong here. I am just finding time to get back into brewing and will continue to look for relevant research myself. I would appreciate being pointed towards any books/papers you would consider required reading.
Cheers
Matt
This this one on here Barge.
https://aussiehomebrewer.com/thread...for-the-novice-and-experienced-brewers.97940/
https://aussiehomebrewer.com/thread...for-the-novice-and-experienced-brewers.97940/
Barge
Quite agree on the research side of things, research takes funding and the money comes from big breweries and is often spent to solve their problems. We as home brewers really do get hind ***. A lot of the research being done is way to esoteric to be useful to us, but the fundamentals don't change whatever the scale.
Point of fact, most research is conducted on pilot plants, usually these are in the 50-150L range so not too far from where most of us are brewing. Gives a pretty fair indication that what works at a large scale also works at our size.
There is some change in the above, with the rising number of small breweries (particularly in the US) there is a lot more research being focused on the needs of smaller breweries. for example look for anything by Thomas Shellhammer if you are interested in using hops.
Other than that, if you want some really good well researched basic information try the IBD website http://www.ibdlearningzone.org.uk/brewing-exam-resources
Read the stuff by O'Rourke and by Bamforth, I would download all those articles they are PDF's and considering the way the IBD is going I'm surprised they are still free.
There is an O'Rourke on the role of Oxygen, its mainly focused on UK Ale brewing (medium sized plants mostly) and there is nothing in it that I wouldn't take onboard.
I have seen NEIPA go from beer to dishwater virtually overnight, caused by too much O2 pickup during filtering (it was a pretty chunky hop soup that needed filtering) so I think its fair to say that we need to be aware of how much O2 we expose a beer to, its going to be more important in some beers than others. Clearly the more hops the more you need to prevent O2 exposure, to the point where next time I do something that's highly hopped I'll be going totally postal on the whole LoDo thing from start to finish. Wouldn't do that on a Hefei, it simply doesn't matter as much.
So yes, some research will have more importance to us than will other, one point that I think many people fail to recognise is the cumulative impact of cutting lots of corners. It might not matter much if you don't mash at the optimum pH, do a 10 minute shorter mash, a 30 minute boil rather than a 60 or 90 minute boil... But add up all the small effects and you end up a very different beer than intended. In my experience its never a better beer.
Based on a few of decades of brewing and study, I try to make the best beer I can, make every decision on quality rather than quantity or price.
Add it all up and we are talking an hour or two (and hey I enjoy brewing) longer and costing a little more but I believe I get better beer.
The cost of making the best beer I can is really only a fraction of what it would cost to buy an equivalent beer but for the time and money I invest it better be equivalent in quality or its my fault.
Mark
Quite agree on the research side of things, research takes funding and the money comes from big breweries and is often spent to solve their problems. We as home brewers really do get hind ***. A lot of the research being done is way to esoteric to be useful to us, but the fundamentals don't change whatever the scale.
Point of fact, most research is conducted on pilot plants, usually these are in the 50-150L range so not too far from where most of us are brewing. Gives a pretty fair indication that what works at a large scale also works at our size.
There is some change in the above, with the rising number of small breweries (particularly in the US) there is a lot more research being focused on the needs of smaller breweries. for example look for anything by Thomas Shellhammer if you are interested in using hops.
Other than that, if you want some really good well researched basic information try the IBD website http://www.ibdlearningzone.org.uk/brewing-exam-resources
Read the stuff by O'Rourke and by Bamforth, I would download all those articles they are PDF's and considering the way the IBD is going I'm surprised they are still free.
There is an O'Rourke on the role of Oxygen, its mainly focused on UK Ale brewing (medium sized plants mostly) and there is nothing in it that I wouldn't take onboard.
I have seen NEIPA go from beer to dishwater virtually overnight, caused by too much O2 pickup during filtering (it was a pretty chunky hop soup that needed filtering) so I think its fair to say that we need to be aware of how much O2 we expose a beer to, its going to be more important in some beers than others. Clearly the more hops the more you need to prevent O2 exposure, to the point where next time I do something that's highly hopped I'll be going totally postal on the whole LoDo thing from start to finish. Wouldn't do that on a Hefei, it simply doesn't matter as much.
So yes, some research will have more importance to us than will other, one point that I think many people fail to recognise is the cumulative impact of cutting lots of corners. It might not matter much if you don't mash at the optimum pH, do a 10 minute shorter mash, a 30 minute boil rather than a 60 or 90 minute boil... But add up all the small effects and you end up a very different beer than intended. In my experience its never a better beer.
Based on a few of decades of brewing and study, I try to make the best beer I can, make every decision on quality rather than quantity or price.
Add it all up and we are talking an hour or two (and hey I enjoy brewing) longer and costing a little more but I believe I get better beer.
The cost of making the best beer I can is really only a fraction of what it would cost to buy an equivalent beer but for the time and money I invest it better be equivalent in quality or its my fault.
Mark
Thanks Mark and Reg. Lots of info there to get me started.
Totally agree that focusing on quality over quantity is the way to go. I was guilty of cutting corners to save some money. Happy to say that I know better now.
Anyhow, apologies for the temporary hijack... looking forward to hear more about Ghostie's open fermentation venture.
Totally agree that focusing on quality over quantity is the way to go. I was guilty of cutting corners to save some money. Happy to say that I know better now.
Anyhow, apologies for the temporary hijack... looking forward to hear more about Ghostie's open fermentation venture.
Ghostie
Active Member
Ambient temperature is what I am using because my fermentor fridge already has a kolsh fermenting and my fermentor for the open fermentation is too big for the fridge.
I scraped the kraussen off because my research (youtube) showed that it is a good idea to scrape the brown bits (i think this is trub) off and to stir the yeast up a bit for a more effective fermentation.
Very 1960-70's thinking on the subject
More modern view is that
1/ there is a very finite amount of "head building" ingredients, skimming takes from that amount.
2/ that skimming "cleansed" the beer, the brown bits are mostly fairly insoluble hop products and that removing them was thought to be a good idea. These days the thinking is that they mostly windup stuck to the sides or being insoluble, in the trub.
3/ It was done to crop yeast, still a valid option in some breweries, removing the early brown foam and cropping from the later heads does yield pretty good quality yeast with little trub. However unless the process is conducted in a very clean environment the amount of infections in the next generation is a real problem.
Open fermentation is really a thing of the past, people with open fermenters may still be using them. But really no one (with a couple of exceptions) is installing new open fermenters. Closed CCV/Unitank type systems have proved to be the best answer in terms of space, fermentation and infection control as well as yeast management...
Mind you skimming off yeast before the ferment is complete also reduces the population doing the fermenting so I cant see how that helps.
Another point is how protective that reported layer of CO2 is, bits of dust carrying bacteria will fall through it, walk past and you will stir it up enough to loose any protection it may be giving.
I know people will keep digging up dated processes and re-discovering them, truth is that a good clean fermenter in a temperature controlled environment will give good results more often than anything else.
Its fun to try new things but don't think its some magic bullet that will make a massive change to your beer.
Look at what bigger brewers are doing and why. The industry standard is temperature controlled closed fermenters operating at or near atmospheric pressure - this is how the best beer in the world is brewed!
Mark
More modern view is that
1/ there is a very finite amount of "head building" ingredients, skimming takes from that amount.
2/ that skimming "cleansed" the beer, the brown bits are mostly fairly insoluble hop products and that removing them was thought to be a good idea. These days the thinking is that they mostly windup stuck to the sides or being insoluble, in the trub.
3/ It was done to crop yeast, still a valid option in some breweries, removing the early brown foam and cropping from the later heads does yield pretty good quality yeast with little trub. However unless the process is conducted in a very clean environment the amount of infections in the next generation is a real problem.
Open fermentation is really a thing of the past, people with open fermenters may still be using them. But really no one (with a couple of exceptions) is installing new open fermenters. Closed CCV/Unitank type systems have proved to be the best answer in terms of space, fermentation and infection control as well as yeast management...
Mind you skimming off yeast before the ferment is complete also reduces the population doing the fermenting so I cant see how that helps.
Another point is how protective that reported layer of CO2 is, bits of dust carrying bacteria will fall through it, walk past and you will stir it up enough to loose any protection it may be giving.
I know people will keep digging up dated processes and re-discovering them, truth is that a good clean fermenter in a temperature controlled environment will give good results more often than anything else.
Its fun to try new things but don't think its some magic bullet that will make a massive change to your beer.
Look at what bigger brewers are doing and why. The industry standard is temperature controlled closed fermenters operating at or near atmospheric pressure - this is how the best beer in the world is brewed!
Mark
Yep, this was the part I was having a hard time wrapping my head around -> why anyone would do it, but for existing breweries that have 'always done it this way' and those looking to experiment, no problem!
otherwise..Anyway, I hope you get some interesting results Ghostie, if nothing else you sparked some interesting conversation!
Ghostie
Active Member
Yep, this was the part I was having a hard time wrapping my head around -> why anyone would do it, but for existing breweries that have 'always done it this way' and those looking to experiment, no problem!
Anyway, I hope you get some interesting results Ghostie, if nothing else you sparked some interesting conversation!
Thanks......why would I do this? For fun, because I can, for excitement, for better results than what I have been getting, for getting up in the morning and seeing if my beer is infected, to smell the fermentation, to watch the Kraussen gently rise and fall and move, to work out a plan and see it work out, to hope that I can brew a beer that I really love. To sit down with a previous brew and plan the next one.
I’m still in awe of making beer. I love the sound of bubbling and the smell of brewing.
I’ll post some more photos tomorrow but at the moment all is looking good. Geez I hope it tastes ok.
Ghostie
Active Member
A picture I took in Brugges , Belgium last year, a glass floor looking down into an open fermenter. Also, it is common practice in the zoigl villages in Germany.
I like this picture.
So....today at Melbourne time 5pm I have scraped the kraussen off again and checked the brew's current gravity (CG - I just made that up by the way). CG is 1.021 and from what I have seen on youtube my FG needs to be about 1.013 before it goes into the secondary fermentor.
I also gently stirred the brew and the second picture is showing small little bubbles after only 7 minutes of scraping the kraussen off.
I had a little taste of the brew....it is different to my other hefes at this stage....although I had other issues with them such as burning the bottom of the Guton etc. The taste is less of dirt, a little metallic finish...a little weak bodied, no flavours of banana or cloves.
And now to go onto issue no. 34....why is my kegerator producing a foaming golden ale (voyager schooner was used). It is ok but I can't get the temp or the carb right with this one.Anyway....one discovery at a time.
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Ghostie
Active Member
Today I transferred the beer into a closed fermenter. The temperature is 18 dregs, I got 17 liters and the CG is now 1.14.
So.....I’ll leave in the fermentor for 6 days and probably bottle next Thursday night.
So.....I’ll leave in the fermentor for 6 days and probably bottle next Thursday night.
wide eyed and legless
Well-Known Member
"Who dares wins" You should have a read of some of the Ken Grossman articles/interviews why he went down the open fermenter track, he does have filtered air going into the fermentation rooms but I doubt that keeps out all the bugs. As zoigl pointed out on the continent of Europe open fermentation is common. Not always under a glass floor but standing right next to them! Would be wise though to use the cling wrap, just in case. I was reading one of George Fix's books a kitchen or brewing area holds 4 to 5 times more bacteria than other rooms.
I use a malt mechanics conical with the lid in place but not locked down, I never use air locks and rely on a blanket of CO2 generated through the fermentation process, I have been brewing like this for over 10 years and had no bad beers. I have won a number of blue ribbons at the Grafton show and made it halfway up the list in the recent NSW competition. My fermenter sits in a Skope fridge which is temperature controlled to keep the wort at the exact temperature, for ales that is usually 18c before dropping to 10 c, I find that I have no variation, ie. rise or fall once the temperature is set. Not exactly open fermenting, but close.
I secondary ferment in 19 litre kegs primed with dextrose.
I secondary ferment in 19 litre kegs primed with dextrose.
Funny, some brewers are looking to pressure ferment, others are looking to go the complete opposite.
Where does the truth lie? I don't know.
Where does the truth lie? I don't know.
wide eyed and legless
Well-Known Member
I like reading what these guys have to say, you will notice that a couple of posts claim that pressure doesn't slow down fermentation, it doesn't, what it does do in ales is increase VDK .
https://discussions.probrewer.com/showthread.php?2965-Pressure-limit-for-fermentation
https://onlinelibrary.wiley.com/doi/pdf/10.1002/j.2050-0416.1984.tb04242.x
Lots of interesting reading on the Probrewer site.
https://discussions.probrewer.com/showthread.php?2965-Pressure-limit-for-fermentation
https://onlinelibrary.wiley.com/doi/pdf/10.1002/j.2050-0416.1984.tb04242.x
Lots of interesting reading on the Probrewer site.
Ghostie
Active Member
Update - I bottled the Hefe on the 12/12/19 which was 12 days after brew day.
On the Saturday 14/12 I put a 500ml swing top bottle in the freezer for 20 mins and tasted it.
Yes I understand that it was too early and the beer is green and all that stuff.....but i was super keen to find out if the banana flavour I am looking for was present in the beer.
Early synopsis of this brew - no banana.....no carbonation....different taste to my other 2 hefe's that I had brewed. Too early to tell if my experiment of open fermentation worked. I did expect some other flavour to come through even though the beer is green.
Just on a side line......I bottled a kolsch a week previously and on the 3rd day that the beer had been bottled i did the same. I put a bottle in the freezer for 30 min and opened it. Well......in a small kolsch glass from Fruh the beer was it. It had bubbles....it was clear....it had a good taste. I thought I had made it. So the next day I did the same. Except this one was cloudy, no bubbles, and no taste.
Geezus......when I think I know how to brew I get these results that tell me I know nothing about brewing.
On the Saturday 14/12 I put a 500ml swing top bottle in the freezer for 20 mins and tasted it.
Yes I understand that it was too early and the beer is green and all that stuff.....but i was super keen to find out if the banana flavour I am looking for was present in the beer.
Early synopsis of this brew - no banana.....no carbonation....different taste to my other 2 hefe's that I had brewed. Too early to tell if my experiment of open fermentation worked. I did expect some other flavour to come through even though the beer is green.
Just on a side line......I bottled a kolsch a week previously and on the 3rd day that the beer had been bottled i did the same. I put a bottle in the freezer for 30 min and opened it. Well......in a small kolsch glass from Fruh the beer was it. It had bubbles....it was clear....it had a good taste. I thought I had made it. So the next day I did the same. Except this one was cloudy, no bubbles, and no taste.
Geezus......when I think I know how to brew I get these results that tell me I know nothing about brewing.
Ghostie
Active Member
PS.........Wided eyed and legless (WEAL) I owe you a beer. Maybe you can tell me where I need to improve on.
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