Pilsner tastes funny after it was kegged...

[TheHammer0309]

Hello all,

I am new to HBT but have been brewing for about 3 years (1 year extract, 2 years all grain). Until recently I have only brewed ales, with good sucess. I recently made my first pilsner, a German Pilsner, that tasted amazing after I lagered it for 1 month @ 35-37 degrees. After lagering I transfered to serving keg and hooked it up to co2. After 1 week in keezer I took a sample and the flavor was WAY different? It had a funny taste? Almost a real malty/acid flavor? Carbonic acid maybe? Any ideas???

 

[quiet_dissent]

Bumping this year old thread that received no response.

I too recently attempted my first Bohemian pilsner. After a nice, cool fermentation -- the only good thing that came out of this winter weather -- the beer tasted great pre-lagering. Fermentation took about three weeks. I actually lagered in the keg for six weeks. Immediately after placing the keg on Co2, I transferred a bit and carbonated with my Carbonator that night. It tasted wonderful and had the beautiful hop aroma from all the Saaz hops. After a few days, I knew it was not fully carbed and did the same as my girlfriend wanted to try. Again, it tasted very good and still had aroma; the wait was to have in fully carbed on the keg and to clear a bit more. After sitting on Co2 for over a week at 12 psi, it is just about carbonated but has lost all of the aroma and some of the flavor has degraded. It's nice and clear but not the same.

A few things:

I've had this happen to other beers I've had on this Co2 tank (e.g., milk stout, amber, American brown ale). I chalked this up to something I was doing. Each time I brewed again, I changed something. I began closely monitoring fermentation temperatures to make sure I was in the appropriate range for different yeasts. I've made sure to use filtered or spring water. I've cleaned my kegs religiously and bought these new a year ago. I clean with PBW or Oxyclean and use StarSan for sanitizing. I use the Oxyclean and BLC on rotation to clean taplines and flush with hot water after cleaning. I do this every two weeks now to ensure the lines are always clean. In other words, I'm very clean and have tried to address any sanitation issues. I have my girlfriend double-inspect everything -- an extra set of eyes can't hurt.

Why is it the flavor changes significantly for the worse? Could the Co2 be contaminated? When I use the carbonator, the forced Co2 isn't "sitting" on the beer in comparison to the keg. I buy my Co2 from a welding supply company.

I'm hoping to solve this issue on my own. I'm brewing a Citra American-style Hefeweizen today. I plan on bottling half and kegging the other half. Hopefully this will help me trouble shoot the issues. In the meantime, any thoughts?

 

[kerant]

I had another thread on this issue a few weeks back. Same prob, sounds like same taste. As I have 2 kegs on same tank and other is fine I know its not co2. Only thing I can figure is I'm not rinsing PBW out good enough or its the residue from when I spray the inside of tank with starsan??

 

[quiet_dissent]

That's a possibility on my end as well. The last keg I went nuts on in terms of cleaning; I inspected it with a flashlight after a thorough rinse. So hopefully if that is the case, I'll eliminate this issue as well. I also might switch out the Co2 for my next experiment batch in which I bottle half of the batch and keg half of the batch for comparison.

And I can say I'm probably also being over-critical of my pilsner. It actually doesn't taste bad just not as hoppy as it first was.

 

[funnycreature]

That's a possibility on my end as well. The last keg I went nuts on in terms of cleaning; I inspected it with a flashlight after a thorough rinse. So hopefully if that is the case, I'll eliminate this issue as well. I also might switch out the Co2 for my next experiment batch in which I bottle half of the batch and keg half of the batch for comparison.

And I can say I'm probably also being over-critical of my pilsner. It actually doesn't taste bad just not as hoppy as it first was.

Since hops aroma apparently gets scrubbed out with CO2 did you check if you have a leak somewhere? Maybe all your hoppy goodness is escaping somewhere...

 

[quiet_dissent]

I did an initial leak check when I kegged. I didn't realize, though, leaks could contribute to decreased hop aroma, so I'll store that away in the noggin.

It also wouldn't hurt for me to double-check as I did move things around a bit post-kegging. I'm starting to see I need to double-check many things.

 

[day_trippr]

Be ultra paranoid about oxygenation during transfers.
Oxygen wreaks havoc on beer character, and imo aroma is the first victim.
It's really easy to miss what's going on at the keg end of a transfer tube, and if you don't flush a keg with CO2 before transfers, a boisterous transfer is putting air in your beer. Bad juju.

Having had one batch affected by a recalcitrant autosiphon a while ago I decided to completely avoid the whole aeration potential and switched to pushing with CO2 from carboy to CO2-flushed keg. With that, I've pretty much reduced any potential O2 exposure from kettle to glass to whatever air is pulled in during cold-crashing the carboy. And I have an idea for that...

Cheers!

[edit] btw, I've "kegged on [Star San] foam" for years and never noticed it contributing...anything...

 

[Stealthcruiser]

Let's hear it!

 

[day_trippr]

Let's hear it!

I'm thinking a ~1 cubic foot balloon attached to a plastic ball valve attached to a short chunk of tubing that will attach to either a universal bung or a carboy cap. Fill the balloon with CO2, shut off the valve, transport to carboy about to be cold-crashed and attach to bung/cap. Open valve, close fridge door, turn controller to "Crash"...

Cheers!

 

[schokie]

How do you transfer from the carboy using CO2?

 

[day_trippr]

How do you transfer from the carboy using CO2?

I have a carboy cap with a long stainless steel dip tube on one port and a ball lock gas post connected to the other port. The dip tube is connected to a liquid ball lock QD that snaps onto the keg beer post, then I snap a gas QD to the gas post, dial up just enough pressure to get things moving, then sit back and watch the magic happen...

Cheers!

 

[quiet_dissent]

If I had oxygen issues initially, I'm guessing my beer would have tasted like crap on the first tasting from the keg? I left the pilsner in the keg for over 6 weeks. When I initially tapped it, it tasted great. The hop flavor has deteriorated over a short period of time.

 

[kerant]

I have a carboy cap with a long stainless steel dip tube on one port and a ball lock gas post connected to the other port. The dip tube is connected to a liquid ball lock QD that snaps onto the keg beer post, then I snap a gas QD to the gas post, dial up just enough pressure to get things moving, then sit back and watch the magic happen...

Cheers!

Can we get a pick of this next time you do it. Sounds interesting.

 

[grathan]

I changed Co2 suppliers and my beers improved.

As a test you could naturally carbonate half a batch and force carb the other. You can also have the purity of Co2 tested by a lab.

I have 2 tanks, I use only the good supplier for force carb and the other I have used for serving only with no ill effects.


Note that oxidation enters your beer from dozens of sources so there could be a cumulative effect. Though since most people don't have issues and your pretty certain of your process than my guess would be the co2 tank. Though oxidation flavors can take weeks to slowly develop you noticed an abrupt change in flavor. My take on this is likely oxidation from the co2 tank as well as carbonic acid and a subdued beer flavors from the chilling process.

Try warming your serving temps up in your fridge next time and also try naturally carbonating. Also avoid the "shaking technique" and pressures over 25 psi" if you do force carb. Perhaps this problem is in all your beers and you only noticed in the delicate nature of a pilsner.

Here is a neat thread on gas suppliers, don't know how far Hampton would be:
https://www.homebrewtalk.com/f11/an...-fill-co2-tank-virginia-beach-va-area-133884/

 

[day_trippr]

Can we get a pick of this next time you do it. Sounds interesting.

It's going to be a couple of weeks before I keg, but I brewed two batches today, and while I was waiting between additions I staged a typical carboy-to-keg transfer using my CO2 push rig.

First shot shows the details: carboy cap clamped to carboy neck, stainless dip tube through one port with tubing attached (and a black/liquid QD at the other end of the tubing), and a gas post clamped to the other port.

Second shot shows everything hooked up. Imagine the carboy has ~5.25g of beer within. I position the dip tube well above the beer level, hook up the beer line black QD to the keg Out post, hook up the gray gas QD from the regulator to the gas post on the push rig, lock the keg PRV open, then open the CO2 tank valve and regulator shut-off. CO2 floods the carboy headspace, the tubing to the keg, and runs down keg the Out diptube, flushing air out via the PRV.

The last shot shows the dip tube slid down near the bottom of the carboy. At this point beer would be flowing up the dip tube, down the tubing to the keg, down the keg dip tube and landing at the bottom of the CO2-flushed keg.

The math says the whole operation uses a little more than one cubic foot of CO2, so the cost is modest to eliminate pretty much the only point where the O2 bugaboo could wreak havoc in a kegging operation...

Cheers!

 

[schokie]

Awesome setup, thanks for pictures. Where did you get the carboy cap with the tubes?

 

[day_trippr]

Awesome setup, thanks for pictures. Where did you get the carboy cap with the tubes?

That's just a standard carboy cap for 6.5g "Italian" glass carboys. They go for ~$3, come in multiple sizes - and you definitely have to get the right size or it's pretty much Game Over before the first pitch is thrown (I had to exchange my first attempt at getting it right).

The gas post is fitting with an adapter to go from the post threads to 1/4" flare, then I used a 1/4" barb to 1/4" MFL fitting which fits in the carboy cap port perfectly.

The 3/8" stainless tubing was cut and bent for me for $10, but you could get essentially the same thing here for around the same price. I used stainless instead of polycarbonate for the wider ID (stainless tubing is much thinner wall than polycarbonate) but one could use a polycarbonate racking cane with the likely slower transfer rate...

Cheers!