i want to just start brainstorming as i conceptualize my next and much much improved brewing and fermenting system.
Please just throw whatever you want at the wall in here and I will listen and thank you. I am going off the premise from the beginning that cold-side oxidation is bad, and I feel like I want to take steps to minimize it in my homebrew.
Final note: I want to do a bunch of this DIY, I have access to a huuuge variety of 304 and 316 stainless steel pipe fittings, hydraulics etc for much cheaper than homebrew supply stores. But, TBH I personally have less hands-on experience designing and assembling these things than most advanced homebrewers.
im not sure if i will be using a small additional fermentation aka “naturally” with added sugars like bottling but in a keg or force carbing, probably the former most of the time.
“problem” is simply relative. my beer is good now, but i want to make beer that has a longer lasting sweet spot, and the consensus is that reducing oxidation is a big part of that.
These are the steps I take: only dry hop during active fermentation no later than 75% complete, don’t open the fermenter afterwards, use fermentation CO2 to push no foam sanitizer from 100% filled keg, purge fill line with beer, close transfer to keg, slowly reduce to cold condition under CO2 pressure, keep cold and drink fresh.
For competition entries: dose each bottle with yeast and sugar, purge bottle 45 sec with CO2, counter pressure fill, cap w/ O2 scavenge caps, crimp w/ bench capper w/ machined bell, check w/ Go — No Go guage, referment in the bottle.
Seriously I would just try naturally carbonating. I add about 1/4 to 1/3 cup table sugar to my keg and rack over. I don’t purge with CO2 and I dry hop in the keg. I try not to splash when I rack over.
I have kegs on for months and I even dispense by beer engine using a cask breather. No oxidation that I can taste.
How long do you allow for the second fermentation? I am actually trying that right now. My beer was racked onto table sugar in the keg 8 days ago. My plan is to leave it at room temperature for 3 weeks and then refrigerate. It may sit in the fridge 2-3 weeks before it gets to the front of the serving line.
@HEUbrewer - i’ve been exclusively “naturally carbonating” for many years. it works, and i understand the nature of oxygen scrubbing. i want to go deeper on this. this will likely be both a change in setup as well as change in schedule/timeline.
im straight up as always - all beers oxidize. i notice it even more since i have always tended to make strong beers that sit around for a long time, and they absolutely do oxidize in varying degrees and ways over time.
@tommymorris
I was walking just now and thinking, and:
-i secondary due to the nature of my setup and some excuses/beliefs i have
-one of the surprisingly crisp and fresh beers i had over the past few months was one i primaried for only something like 2 weeks (i usually go 4+) and “secondaried” to get the yeast off for just 2 days and cold at that. it really made me think that i need to considering changing my schedule.
so length of time is something i want to change by using a system that allows for more intense cold crashing without physically moving the carboy.
this is stuff a lot of people already have in place i know, i know.
my plan is to get a big horizontal freezer and make it a fermentation chamber, likely using a pump unit to transfer, then carbonating with sugar in a keg.
Use oxygen barrier tubing on both gas and beverage lines. Switch out your keg lid o-ring for one of the low-O2 permeability ones. Avoid silicone anywhere.
I sometimes naturally carbonate, especially for Belgian and English styles (no particular reason - it just feels “right”). Usually I force carb, and it’s fine. For dry hopped beers, I’m a lot more careful about hop handling nowadays - I more frequently dry hop loose in the fermenter and then cold crash (versus meshed in the fermenter or keg and then pulling them).
The biggest improvement for me was to do closed transfers into purged kegs, and then ice-cold storage. I use BrewTanB on the hot side. I’m not horrifically fussy about oxygen reduction otherwise, and get results I like. I’ve definitely noticed improvements on my light lagers - where they were noticeably oxidized after 2 or 3 months in my old regime (open transfer into non-purged keg, no BrewTanB), they stay quite fresh for 3 or 4 months (until the keg is finished).
Once I started force carbonating after cold crashing in the primary, I noticed an immediate degradation in my beer from the fermenter sample to keg. I assumed something was wrong with my process, since in theory I was reducing air exposure and the possibility for off flavors by crashing under 1-2 psi of pressure, clearing the yeast, purging kegs full of sanitizer, and using closed transfers. But somehow my beer was worse than when I just racked into an open keg while fermentation was winding down, chilling for a few hours and shaking the keg under 30 psi. It’s possible that having a bit of yeast at the tail end of active fermentation was actually protecting it.
Obviously, it depends on the purity of CO2 that you are given. 99.9% sounds good but is objectively poor for force carbonation via injection. The only conclusion I can come to is that the CO2 I get is not great.
re: 2 to 3 months noticeable oxidation (depends on the beer, but i know what you mean in principle) vs aiming for 3 to 4 months staying relatively fresh - that is exactly what i’m aiming for.
i saw a post here on duotight fittings, and i definitely want something that is highly removable/modular if needed too. i am familiar with the concept of these kind of push to connect fittings and can imagine that.
@Narvin - one of the reasons i do the process i do up until now was that i like clarity for appearance and perceived taste elements. but it was always a trade off between fresher beer and somewhat less clarity vs. clearer and beer that may age faster. anyway yeah
Interesting topic and potential solutions. I have a question after reading through the thread. How much difference is there in using a keg filled with sanitizer and doing an oxygen free transfer from just pressuring a keg with CO2 and then doing the transfer without the sanitizer fill all the space?
Trim the gas dip tube in your serving keg so that you can really fill it all the way up with sanitizer to push out all of the air prior to transfer
Rack beer into serving keg when it is still fermenting and there are a few gravity points left to drop; the active yeast will scavenge the oxygen that gets picked up during the transfer
Use a spunding valve on the serving keg to naturally carbonate the beer as it finishes fermentation; that way you only need to use bottled CO2 for serving; use a floating dip tube to help with clarity since there may be more sediment in the keg with this method
Good question!
Filling with sanitizer and then displacing the sanitizer with CO2 ensures that only CO2 remains in the keg.
Closing a keg and then pressurizing it with CO2 means that you have CO2+all of the atmospheric air (including oxygen) that was in the keg to start with. I suppose if you transfer into a closed keg that has been given a once-fill with CO2 that you get reduced oxygen ingress relative to just an open keg, but suspect the amount of oxygen is still damaging. You could do a purging cycle to dilute the oxygen (and nitrogen…and other goodies), but it would take a lot of purge cycles (and CO2) to get it down to a minimal oxygen content in the keg. (I have seen calculations of this, but I’m also a bit wary because the world is a complex place and the simplifications of back-of-the-envelope calculations don’t necessarily match reality).
Yes, it can take 15-30 cycles of filling with CO2 and venting to dilute the O2 content to an acceptable level. I sanitize my keg and then send the fermentation gas through the keg and into a blowoff jar. The keg is thoroughly purged of oxygen by the time fermentation is complete.
I like to keep it simple, and do several things already mentioned. I ferment at the yeast’s preferred temp for about 4-7 days, then let it rise slowly (basement temp 60-70F) until I keg it on day 7-10. I do not pressure ferment or purge the keg before I siphon from the primary into a sanitized keg. A vast majority of the time I add table sugar to the keg for natural carbonation. I then turn up the CO2 pressure to 30psi and purge 3-4 times. This uses very little CO2. After a week at my basement ambient temp, I refrigerate it to 35F for 1-3 weeks before calling it done (numerous “samples” in that time period). I have never noticed a concern with any of my beers, even the lighter lagers (4% ABV/2.5 SRM/12 IBU Light American Lager style). Most stay on tap for 2-3 months and seem to only improve with time. I do not keg bigger beers (>7%) since I prefer to store them longer. I have thought about reducing potential O2 in the cold side, but I doubt I would be able to notice the difference for my circumstances.
This may be a little crazy for some, but I went down the same road in 2019. My beers have been very much improved since then.
I have switched to fermenting in tall 1/4 barrel Sanke kegs. I was interested in brewing 5 gallon batches, so the extra room provided by the 7.75 gallons was perfect. Plus they are tall and fairly skinny for an easy keezer fit. The problem comes in with how to go about it. After doing research I decided to modify the Sanke so I could reduce oxygen with closed transfers, pressurized crash cooling and pressure fermenting all in one vessel. The idea was to not have the beer see atmosphere once the yeast was pitch until it was in a glass.
The thing is, I needed to open the fermenter to add dry hops and clarifiers, so I added two gas ports ports to the top, liquid comes out the 2" top. When I need to open the top of the fermenter, I drop the pressure in the fermenter to @ 2 psi. I then hook co2 to the one port (2-3 psi) and vent through a airlock with the other port (a gas fitting to a hose into a water filled beer bottle is my air lock). That keeps the pressure in the fermenter positive, so that when I open the top, the gas vents out 2" opening. I add hops or whatever and close it back up. The regulator is set to @ 2-3 psi and the air lock vents again when I close the top. I vent for another 2-3 minutes just in case I got some oxygen ingress and then I remove the airlock and pressurize the keg to whatever it was before.
The system allows me to pressure ferment (or not), closed transfers, spund the beers and I can also serve from the ferment if I choose. I found that spunding the beer has saved me a boat load of co2. I wait until the beer is @ 90% done, then allow the pressure to come up to @ 25-30 psi. The nice thing about a variable pressure relief valve (blowtie or similar) is that if you spund too soon, the valve just vents the extra co2 off.
After dry hopping you can do the same thing, I have even carbonated a beer with hop creep.
Here’s a few pictures. They show the floating pickup I use too.
How do you add the sugar for a natural carbonation if you are doing a closed transfer? I feel like that question got answered at some point by at least one person, but I can’t find the thread, if it isn’t entirely my imagination. I’ve thought about adding sugar syrup through the fermenter’s airlock hole.
