Sterilizing kegs

Brewing Processes
1

I was curious as to how everyone sterilizes their kegs. Seems straight forward, but apparently not so for me.

I’ve had this perpetual problem where some of my beers are being slightly infected with what I think is lacto. I’ve determined that it’s likely the kegs because I just tried some from the keg, has that sour twang to it, and the bottles (that I was saving for competitions now that I’m actually starting to do that) didn’t. You’re probably asking if I tasted it when I bottled/kegged it as well as take the FG: yeah, I did. I just don’t remember tasting the twang, though I’ve discovered I have a hard time picking it up in a non-carbonated and warm beer, as I’ve kegged beer that was clearly infected and didn’t really notice it at kegging time, so who knows.

I store my kegs filled with water with a couple cap fulls of iodaphore, clearly this doesn’t seem to be enough. Every keg that I go through now I’m washing with PBW, boiling the posts, and running a torch along the dip tube to make sure anything that’s in there is DEAD. Then running a gallon or so of star san through it, and storing it with the star-san and giving it a shake every couple of days. I haven’t kegged anything since I started this regimen, I’m hoping it’ll be enough … this is miffing me off, I’m likely going to pour out 10g of american amber that actually came out reasonably good, and I just finished a pale ale that had a similar problem and just wasn’t that enjoyable, I just had a hard time dumping it. I’m now past that point.

2

At least water the garden with it, don’t just go down the drain.  :cry:

PBW followed by StarSan one after the other is all I’ve ever had to do. Shake the heck out of the keg with pbw, dump it into next keg to be cleaned (repeat), make a big batch of StarSan and pressurize that keg - then I’ll run all that through my beer lines, and catch it on the other side into another clean keg to sanitize it and run through the other beer line. I’ve only replaced all the gaskets upon initial purchase - YEARS ago. Maybe I’m just lucky so far.

3

It sounds like you’re being quite thorough (torch) and removing the posts each time so I’m a little surprised.

I was going to suggest changing all the gaskets if you haven’t, yet.  Otherwise, you might try an oxycleaner.  There is the name brand stuff that’s pretty expensive but you should be able to the find a generic brand for much less.  I can get a tub for $2 and it has the same active ingredients.  Usually found around the laundry detergent section in your local big box store.  I swear by it.  I also use it in my carboys after fermentation and it removes the crusty krausen without scrubbing!  I haven’t had an problems using oxycleaners with regards to infection, flavor, or any other issues.  I always rinse thoroughly and also follow up with StarSan or Iodophor.

I’m also wonder about the kegging process.  Is it similar to bottling?  Are you using a different set of equipment for kegging that the beer comes in contact with that could be the source of the problem (tubes, siphon, racking cane, cane tips, etc.).

Also, I don’t know if you have multiple kegs, but is this problem isolated to one keg?

4

Thanks gents. Sounds like I’m hopefully on the right track.

I don’t usually remove the posts, that’s a new extra sanitation step that I’ve been taking.

The bottling process is pretty much the same for my kegging: in fact, I’ll bottle a dozen bottles using the same tube, just hooked up to a wand, then when done bottling the few bottles that I want to do, I’ll hook up to the tube to a ball lock and hook it up to the keg and keg away. I’ve switched between using the ball lock or just letting the tube dangle inside the co2-purged keg with the lid removed, both have had issues, so I don’t think it’s the ball lock, especially since it’s rinsed and dunked in star-san even if I look at it wrong.

It’s been several kegs, which also contributes to my overall confusion: How does an infection go from one keg to another? I have about 13 kegs in total, and I haven’t tracked which ones have had infections and which ones haven’t. This I will start doing now that I’ve determined it’s not just a couple of funked batches and there’s a problem somewhere.

I think it’s possible I had a batch of bad beer in the carboy that went bad (that has since been fully sanitized.) And between the couple of batches that I’ve done that have gotten funked, they were hooked up to the kegerator, then later non-infected batches being hooked up to it that probably had some infected beer left in the line, etc, I can make loose enough connections to see how it happened and spread across multiple kegs, while not necessarily fully infecting that keg, but having enough of the bacteria left that survived the iodaphore that when I did keg the next batch, whammo. Which is one of the reasons I’m going crazy with the cleaning/sanitation regimen. Whenever a keg is now emptied, before I hook up the new one, clean the old with PBW, run the PBW through both beer lines (I have a dual faucet) just in case, rinse, run star-san through, keep star-san in the keg ready for the next batch.

If this persists, I think changing the gaskets in addition to everything else will be the next step. Though I think the few minutes the gaskets spend in with the barely boiling water should kill most things, and whatever does survive, the spritz of star-san should take care of the rest. But if this doesn’t get better, that will be the next step… quite possibly running boiling water through all of my kegs as well. Chemicals can’t get everywhere: heat can. I just hope I don’t have to go to that level.

And yeah, when I do pour the beer out, it’ll be into the mulch pile which will feed my hops the next year, so the circle of beer life will continue :slight_smile:

5

Don’t boil the gaskets, instead purchase new ones. I generally do not recommend this, but since you believe the kegs to be the source of infection, mix a weak bleach solution -maybe 1/2 tablespoon per gallon- and put into the keg for a few minutes. Rinse thoroughly and then fill the keg with near boiling water. Dump and sanitize with StarSan solution keeping contact to ALL parts of the keg for at least 5 min. If that procedure plus new gaskets doesn’t kill whatever is bugging you, then your issue is somewhere other than the keg.

One last thought - You are pulling the poppets from the posts during your cleaning regime before you sanitize, correct? Sanitizing without proper cleaning is a bad deal!

6

Gasket kits for 13 kegs is going to add up :slight_smile: But yeah, I’ll do what I have to. I do clean before I sanitize, as you can’t sanitize something that’s not clean!

I had briefly thought about a quick bleach rinse, but was hoping the star-san would be just as effective. I’m afraid that even a quick bleach rinse will pit the metal allowing whatever’s bugging me to hide even more effectively.

7

No so much if you get them from here:  http://www.mcmaster.com

I don’t have the part numbers available to me right now, so maybe someone else can chime in.

8

I cut and pasted them into a FAQ on my thumb drive for these situations.

McMaster Numbers and Prices on January 2005
Dip Tube O-Rings [I use the same ones for both pin- and ball-lock kegs]
9452K172 BunaN #109 Pkg 100/$2.24

Post O-Rings
9452K23 BunaN #111 Pkg 100/$2.77

Lid O-Rings
9452K218 BunaN #417 Pkg 10/$12.50

Paul

9

Have you replaced your beer lines? If they’re the source nothing you do to the keg will help.

10

And you need to find out where the lacto came from.

I have been having the same problem off and on and now I think it is from fermenting in the same room where I store my grain. Lots of lacto in the air from weighing out the grain.

Now I ferment in a different room. We’ll see.

11

Kegs pitting will not be an issue if the contact time is kept relatively short (a few minutes) with a weaker than normal sanitizing solution of bleach.

The thought process is the bugs must have become resistant to your sanitizer. The bleach will throw them a curve ball, the heat will fry their butts and the StarSan for 5 min will ruin the day of anything you have which may remain after you finish bleaching and heating.

Rinse the bleach as many times as required until no scent of bleach remains.

One other thought, are you rinsing after the iodophor?  If so, perhaps your water is to blame.

12

My process for keg use is as follows:

Ferment in keg
Transfer by CO2 push to sanitized and purged keg

Remove posts and lid
Inspect all soft parts; post orings, dip tube orings, lid oring, poppets. Replace as required. I keep a goodie bag of all these parts on hand.
drop all components in keg
Fill with hot water and “Oxi”-cleaner (generic)
Soak overnight
drain and rinse
reassemble
Fill with Starsan and hold while working on the next keg
Transfer starsan to next keg (I transfer out to out on the keg)
Pressurize to 10 psi with CO2
Mark and set aside for next use

My last keg of the day gets to keep the starsan until the next session.

my starsan is mixed with distilled water to ensure long usability

I have not had any issues of flavor carry over (from sodas) or infection, even with the previous batch holding a Brett or Lambic style.

I generally leave them in the keg for several weeks until I can bottle (beer gun) or place in service with no ill effects.

13

It’s also not a problem if you allow oxygen to reach the stainless after using bleach. That will regenerate the oxidation layer which is destroyed by the bleach. Like Matt said, just don’t store bleach water in them.

Kai

14

I agree with above that one should not store bleach solutions in SS kegs or kettles, but remember that it takes 20 minutes contact time to sanitize the pre-cleaned surface (compared to just 1-2 minutes for Iodophor or StarSan), and not “a few minutes.”  JP (“How to Brew”) recommends 1 tablespoon (0.5 oz) of bleach per gallon of water as the ideal concentration for bleach sanitizing solutions.

Sean makes a good point about the beer lines.  And the advice to completely diassemble the kegs (poppets and all) and clean them thoroughly is right–a big chore, but the right thing to do; especially if you’ve never done it or haven’t done it in awhile.

Clean everything that touches your wort once it has been chilled.  Consider replacing any rubber or plastic equipment (hoses, stirrers, stoppers, spigots, gaskets, etc.).  At the very least, thoroughly clean the kegs, put in new gaskets, ferment in new plastic buckets (or glass carboys), and upgrade to SS stirrers and new hoses.

Good luck with getting the brews tasting like they should again.

15

All good feedback! Thanks everyone! I’ll let you know how it goes, and I’ll go ahead and order a few sets of new gaskets as well from McMaster, I’ve got a few items in my cart that I need to pull the trigger on anyway.

16

I once researched it long ago (2001) and came up with a 10 min contact time with 200ppm bleach (FWIW - 1/2 tbsp should be 100 ppm).

I checked Palmer and he does suggest 20min, so I decided to do a little research and came up with a link on food surfaces from Auburn. The USDA suggests no less than 50ppm and no more than 200ppm. Water should be 105-120F and remain in contact from 1-5 minutes and anything less than 200ppm is supposedly a no rinse concentration, but we all pretty much know the bleach smell is a no no. Further it says, “However, chlorine sanitizers can corrode equipment and should not be in contact with stainless steel surfaces for more than 30 minutes.”
http://www.ag.auburn.edu/poul/virtuallibrary/mckeeeffectivechlorine.html

So my answer of 100ppm and a few minutes was initially wrong, but now is miraculously validated  ;D

More miraculous validation, if anyone still cares…
http://nrckids.org/CFOC/PDFVersion/Appendix%20I.pdf

http://www.charmeck.org/Departments/Health+Department/Environmental+Health/Educational+Info/Brochures/chlorinesanitizer.htm

17

You may need to replace your gas lines.    I had a similar situation about a year ago… 3 kegs in a row went sour.    Eventually I tracked it down to my (opaque) CO2 line.  Apparently I had neglected to vent a pressurized keg before hooking up the gas, and it shot a bit of beer into the tubing.    I replaced the gas line (with clear tubing) and haven’t had a problem since.

18

Good point. I just noticed that some (thankfully non-infected beer) beer had managed to back flow into my co2 tank while I was force carbonating through the bev out line. I’ll likely just toss all of my tubing, put the co2 tank upside down, purge the beer out, and the next time the tank has been emptied stuff it in the oven with the valve open and heating it up to ~200F for a short while to kill any possible infection in there, and then clean out the regulator as best I can with starsan and what not.

19

I have a manifold with 6 gas lines and all my lines are now protected by check valves since I back flushed the system with a naturally fermented cider. McMaster Carr has them for about 6 bucks a piece. Well worth the cost to save a batch or 2. This can also prevent the cross flavor contamination that some people experience when feeding more than one keg from a single regulator.

20

Not to be picky, but we sanitize kegs.  We do not sterilize them.