Cold Crashing and Oxygen

[EDF713]

Those carboy caps allow you to easily do a pressure/closed transfer with a racking cane and some CO2. I'm surprised you didn't use it to your advantage.

I am too, I didn't think of it until I switched to spunding and taking cold side oxidation more seriously. I've thought of it since, I have an old racking cane I don't use any more. Now I'm either spunding early or using a tall pinlock to ferment in if it's a lager. I may try it, sometimes I wonder if siphoning to my spunding keg is still introducing too much O2.

 

[EDF713]

https://www.brewhardware.com/product_p/ccguardianv3.htmhttps://www.brewhardware.com/product_p/ptrcarboyecon.htm

Both kits are good deals, it's worth it just not having to round up the parts if you don't have them.

 

[EDF713]

@IslandLizard and @EDF713 Did you ever get any funky flavors from the mylar balloon post coldcrash? I’m going to do something like this with my next batch but was planning on using a liquid catch bag from a medical supply company. However mylar balloons are much easier and cheaper to source.

I never noticed a problem. If you get a normal sized balloon it doesn't such back the whole volume.

 

[IslandLizard]

@IslandLizard and @EDF713 Did you ever get any funky flavors from the mylar balloon post coldcrash? I’m going to do something like this with my next batch but was planning on using a liquid catch bag from a medical supply company. However mylar balloons are much easier and cheaper to source.

I've read about wicked aromas inside those balloons. Maybe from the printing inks?
Can it be flushed out with fermentation CO2?

I'm using a mylar bag that contained hops.

 

[renstyle]

I ferment 5.5 gallons in 6.5 gallon carboys. I doubt those jars would hold enough CO2 from fermentation to supply the "suck-back" volume without O2 entering the equation (that entire rig will flow in reverse pulling in outside air)...

Cheers!

I agree, the jars in the pic/link are on the small side. I was just trying to include a visual to accompany my text to illustrate the idea I was positing

 

[Ogilthorpe2]

https://www.brewhardware.com/product_p/ccguardianv3.htmhttps://www.brewhardware.com/product_p/ptrcarboyecon.htm

I have the cold crash guardian. Only used it once so far, seems to work as advertised.

 

[NGD]

I've read about wicked aromas inside those balloons. Maybe from the printing inks?
Can it be flushed out with fermentation CO2?

I'm using a mylar bag that contained hops.

Hop aroma CO2 bags for *extra* aroma. This sounds like a product waiting to happen.
I’ve read the same comments which makes me wonder if its a wise thing to do. Seems as though plenty of people have done it with no ill effects though. Crash guardian sounds like a safer bet.

 

[Beer666]

I use a blow off tube with a syphon tap halfway along. When i crash i turn off the tap and it will suck the lid in a little. Obviously i am using buckets.

 

[Bobby_M]

I use a blow off tube with a syphon tap halfway along. When i crash i turn off the tap and it will suck the lid in a little. Obviously i am using buckets.

Buckets are notorious for leaking at the huge lid seal. If the lid only sucks in a little, you are very likely getting some gas sucked in.

 

[Beer666]

Buckets are notorious for leaking at the huge lid seal. If the lid only sucks in a little, you are very likely getting some gas sucked in.

Hi Bobby, My buckets are fairly robust but i know what you mean. Would like to buy one of your guardians if you ship to the UK?

 

[kenmcchord]

While I'm waiting on the latest version of the Cold Crash Guardian from Bobby...today I've improvised what I hope to be a good solution to avoid the O2 invasion.

I filled the blue top keg with starsan, emptied that into another keg with forced CO2, then hooked up the tube pictured above with a fluid ball lock to a sanitized hose that would fit the blow off fitting. I purged the line as best I could with CO2 then made the above connection, and added an open gas ball lock to the gas post. I'm figuring that CO2 is heavier than regular air so the CO2 ought to stay low in the keg, and pulling any gas from the fluid post should get the gas that is lowest in the keg.

I'm hoping this is better than just leaving the fitting wide open, and I really wanted to cold crash since I have the glycol chiller. I mean, really this can't be any worse than leaving it wide open, right?

Comments?

 

[marc1]

While I'm waiting on the latest version of the Cold Crash Guardian from Bobby...today I've improvised what I hope to be a good solution to avoid the O2 invasion.

View attachment 704362

I filled the blue top keg with starsan, emptied that into another keg with forced CO2, then hooked up the tube pictured above with a fluid ball lock to a sanitized hose that would fit the blow off fitting. I purged the line as best I could with CO2 then made the above connection, and added an open gas ball lock to the gas post. I'm figuring that CO2 is heavier than regular air so the CO2 ought to stay low in the keg, and pulling any gas from the fluid post should get the gas that is lowest in the keg.

I'm hoping this is better than just leaving the fitting wide open, and I really wanted to cold crash since I have the glycol chiller. I mean, really this can't be any worse than leaving it wide open, right?

Comments?

The gasses will mix readily. Popping a spunding valve onto that keg set to low pressure will prevent any O2 coming back in.

 

[kenmcchord]

The gasses will mix readily. Popping a spunding valve onto that keg set to low pressure will prevent any O2 coming back in.

I don't know what a spunding valve does. I guess I need to research that. I've probably already had significant O2 contact at this point if the gasses mix that readily. Probably try to keg it in the morning then, live with what I've got.

 

[marc1]

I don't know what a spunding valve does. I guess I need to research that. I've probably already had significant O2 contact at this point if the gasses mix that readily. Probably try to keg it in the morning then, live with what I've got.

A spunding valve is a one way valve that releases at a set pressure. So you set the pressure to a few PSI and whenever the CO2 builds over that, it will release it. I've had a couple, the Kegland one performs much better than the other brass one. If your fermenter is capable of holding pressure, when there's a few points of fermentation left to go, you can raise the release pressure and get most of your carbing done without your CO2 tank.

 

[Jim R]

Why don't you just do a pressure transfer to the keg at the end of fermentation and then cold crash in the sealed keg.

I use the same SS Brewtech fermenter. I usually let my beer ferment for 2 weeks in the fermenter in my temperature controlled refrigerator (usually with the temperature in the mid 60's). Then I basically take my blow off tube and hook it up to my CO2 tank to apply 1-2 psi of CO2 pressure to the fermenter to do a pressure transfer to my keg. I put the fermenter on the countertop and the keg on the floor to get the benefit of gravity also. Before the transfer I fill the keg with Star San and purge it with CO2. Then after the pressure transfer I simply cold crash the sealed keg with no concern for oxygen exposure or suck-back into the fermenter. Of course, I carbonate in the keg at the same time as I am cold crashing.

 

[jddevinn]

If that's all you have instead of putting the open gas in line put CO2 into the keg at some low pressure and then disconnect the tank. When the flow slows down add some more CO2 and repeat using the keg as a buffer.

 

[Baglorious]

I have used a fairly simple solution, depending on my fermenter type. I use a ball lock gas post and gas post connector with tube as my blowoff. When fermentation is over and I cold crash, when negative pressure develops, the fermenter "scrunches" (shrinks)... and I simply add some CO2 in from the tank. IIt couldn't be easier, as you can see when the fermenter is 'unscrunched' and back to normal size. Most fermenters, with a little tweaking, can hold negative pressure.

Here are some pic of my highly engineered rig for the couple of Big Mouth Bubblers that I own. Just a simple carbonation cap and a self-drilled stopper. (I added a stainless washer just to form a better 'flange'... but that isn't really necessary.) It is obvious that this works well, and it is not allowing air to leak inward, by the amount of visible "scrunch" I can see that holds and does not diminish. (I just finished a batch 2 days ago... and wish I had taken pics.) As an added bonus, the cap/stopper allows me to push from the fermenter for keg filling. (I still elevate the fermenter to transfer... but can slowly add CO2 to keep all oxygen out during transfer. Again, you can see the fermenter flex inward and 'scrunch' during the drain... then add a bit more CO2 to restore the fermenter to full size, and repeat as you drain to keg.)

This could be adapted to any plastic fermenter... as I bet they all can 'scrunch'. (My Better Bottles sure could... they'd scrunch fully when I had a 3 piece airlock in and cold crashed, and I'd watch them "pop" back to shape when I pulled the airlock before I knew anything about the O2 being an issue.)

I bet you could use a stopper and adapt the same idea to an SS brew bucket... as I bet they'd hold negative pressure. (I'd probably add a weight set atop the lid to ensure the gasket could do its job.)

I now mainly use "kegmenter" type 15.5 gal fermenters (SABCO) which make this easy. Using parts from Bobby, I added a spunding valve setup to use for my blowoff. (I don't actually "spund.") That fermenter can obviously hold negative pressure... so I just let it crash, then add the CO2 in when I push to kegs. Essentially, I use the same process with fancier equipment.

 

[kenmcchord]

Well from the sound of your comments I probably got some contact with air in the 12 hours I cold crashed. This morning I went out and disconnected that keg, then reinstalled the blow off tube into a jar of starsan. The beer has been at 35° for the past 12 hours, I've got to think it's contracted all it's going to contract and whatever contact I've got is going to be it.

I get the comment of using the spunding valve, but isn't that a valve that protects over pressure situations? In the case of the cold crash it's the vacuum that's the issue here. I'm figuring I've already created whatever damage I've got, and with the tube in the starsan I have somewhere for any gas that comes from any further yeast activity. Like I said, I have the cold crash guardian in the mail, but that wouldn't probably have helped me in this fermentation. I'm hoping I won't notice any problems, may not be the best beer ever brewed, but I'm learning.

Thanks to everyone that replied, I truly appreciate the tips.

 

[kenmcchord]

Why don't you just do a pressure transfer to the keg at the end of fermentation and then cold crash in the sealed keg.

I use the same SS Brewtech fermenter. I usually let my beer ferment for 2 weeks in the fermenter in my temperature controlled refrigerator (usually with the temperature in the mid 60's). Then I basically take my blow off tube and hook it up to my CO2 tank to apply 1-2 psi of CO2 pressure to the fermenter to do a pressure transfer to my keg. I put the fermenter on the countertop and the keg on the floor to get the benefit of gravity also. Before the transfer I fill the keg with Star San and purge it with CO2. Then after the pressure transfer I simply cold crash the sealed keg with no concern for oxygen exposure or suck-back into the fermenter. Of course, I carbonate in the keg at the same time as I am cold crashing.

Like I said in my first comment it's that I got this glycol chiller and wanted to see how well it cold crashed. In hind sight I wish I had done exactly what you've said here, but next batch I'll have the guardian to protect from O2 contact.

 

[kenmcchord]

A spunding valve is a one way valve that releases at a set pressure. So you set the pressure to a few PSI and whenever the CO2 builds over that, it will release it. I've had a couple, the Kegland one performs much better than the other brass one. If your fermenter is capable of holding pressure, when there's a few points of fermentation left to go, you can raise the release pressure and get most of your carbing done without your CO2 tank.

I'm not exactly sure how much pressure these SSbrewtech buckets can take, so I'd be uncomfortable allowing pressure to build in them. That said I'm eyeing a better fermenter for the future, one that can do much of what you're talking about. Thanks for the explanation of the spunding valve!

 

[kenmcchord]

Holy crap, what a disaster cold crashing became!

I brew in my garage in central Florida where it was 90° and humid today. I have a/c in the garage (4 ton rheem central air handler, works quite well) but when I'm out of the garage I keep in 80°-81°. So once I cold crashed to 36° the moisture coming off the fermenter was pretty staggering, the neoprene insulation cover was soaking wet and there was virtually a puddle under the fermenter. Additionally, after replacing the keg filled with CO2 with the starsan jug and blow off tube, the cycling of the chiller keep making the starsan creep up into the fermenter.

I decided to just keg the beer tonight, so it's in the kegerator now carbing up. Man, I learned a few good lessons with this attempt to cold crash, I'm hoping the Cold Crash guardian will have enough volume of air to allow me to cold crash for a few days. All in all, this batch was a good learning opportunity. I'll do better next time!

 

[Jim R]

That SS Brewtech cooling system seems like an overly complicated and expensive fermentation cooling system especially with a glycol chiller. I found a $180 mini refrigerator at Home Depot that fits that fermenter and works perfect for cooling with a $30 Inkbird temperature controller. It would also work for cold crashing with that Cold Crash Guardian but for someone that kegs anyway it is easier to just cold crash in the sealed keg.

 

[kenmcchord]

That SS Brewtech cooling system seems like an overly complicated and expensive fermentation cooling system especially with a glycol chiller. I found a $180 mini refrigerator at Home Depot that fits that fermenter and works perfect for cooling with a $30 Inkbird temperature controller. It would also work for cold crashing with that Cold Crash Guardian but for someone that kegs anyway it is easier to just cold crash in the sealed keg.

The reason I wanted to glycol chiller was so I could ferment more than one batch at a time, and at different fermentation temperatures. I agree with the cold crash re: kegging, however I was thinking that a cold crash before kegging would eliminate some of the material that would otherwise make it into the keg. Really I'm experimenting with it all right now, I suspect that I have a system that works well for me soon enough. To be clear, I am getting back into brewing after having a few years away and I now have the space and time to play around with a bigger set up.

What is for sure is that without a way of controlling the suck back (as in the cold crash guardian or similar device) cold crashing can be a disaster. I won't attempt that again without some protection.

 

[VikeMan]

I agree with the cold crash re: kegging, however I was thinking that a cold crash before kegging would eliminate some of the material that would otherwise make it into the keg.

You were thinking correctly.

 

[Dland]

If one cold crashes in kegs, after spunding, there is no O2 introduction, and no extra CO2 needed.

Yes, there might be a bit more yeast sediment at bottom of keg. 3/4 inch off dip tubes solves that. Perhaps another case of many ways to make beer, and different preferences of simplicity over love of gadgets and process.

 

[jddevinn]

If one cold crashes in kegs, after spunding, there is no O2 introduction, and no extra CO2 needed.

Yes, there might be a bit more yeast sediment at bottom of keg. 3/4 inch off dip tubes solves that. Perhaps another case of many ways to make beer, and different preferences of simplicity over love of gadgets and process.

I just hate that when I get sediment into the keg that it can be pouring perfectly clear, but then if I pull the keg and move it all the sediment gets stirred up again.

 

[EDF713]

Another option besides cutting the diptube is a floating dip tube, I have a couple of these - Top Draw® Beer Pick Up Tube. This is strongly recommended if you spund or cold crash in the keg. I added a stainless steel nut on the end of the tube with the float since it would sometimes pull air.

 

[Dland]

I just hate that when I get sediment into the keg that it can be pouring perfectly clear, but then if I pull the keg and move it all the sediment gets stirred up again.

There is another case of different preferences for different brewers, w my 12 keg brew freezer/fridge, my kegs remain stationary form crash to kick.

 

[jddevinn]

There is another case of different preferences for different brewers, w my 12 keg brew freezer/fridge, my kegs remain stationary form crash to kick.

Most of the time my kegs stay in the bar at home, however, I've made a portable bar and a couple times a year take kegs to events/parties (well not this year).

 

[eric19312]

Holy crap, what a disaster cold crashing became!

I brew in my garage in central Florida where it was 90° and humid today. I have a/c in the garage (4 ton rheem central air handler, works quite well) but when I'm out of the garage I keep in 80°-81°. So once I cold crashed to 36° the moisture coming off the fermenter was pretty staggering, the neoprene insulation cover was soaking wet and there was virtually a puddle under the fermenter. Additionally, after replacing the keg filled with CO2 with the starsan jug and blow off tube, the cycling of the chiller keep making the starsan creep up into the fermenter.

I decided to just keg the beer tonight, so it's in the kegerator now carbing up. Man, I learned a few good lessons with this attempt to cold crash, I'm hoping the Cold Crash guardian will have enough volume of air to allow me to cold crash for a few days. All in all, this batch was a good learning opportunity. I'll do better next time!

How about running a dehumidifier in the garage?