Issues with Kegging and Taste (Help Please)

I've had a consistent issue of my kegged IPAs tasting somewhat different starting a day after the first connect of the keg, and I'm hoping someone can help me figure out what I'm doing wrong.

After 1-2 weeks of "set it and forget it" force carbonation at around 45 degrees F, the first day I connect the keg to a cleaned and sanitized line and spout, it tastes great. The carbonation is on point and the aroma + taste are exactly as I planned. However, typically the next day or shortly thereafter, while the keg remains connected, subsequent pours of the same beer at the same temperature and what I think/hope is the same balanced pressure, the beer becomes flatter, and the aroma and taste change as well. I have even tried bottling some with a beer gun upon first connection to the keg. The beer coming out of the beer gun on the day of first connection tastes great, but the bottles, which are purged with CO2 before filling, suffer the same flatness when opened a day later.

I'm trying not to have an ego about it, so I won't discount that things may be getting oxidized. The flat taste sometimes can be perceived as papery though the color doesn't change or change much. I'm baffled as to where oxygen may be coming from. I don't leave a lot of headspace in my fermentor during fermentation. I have a small conical fermentor, so I do not transfer to a secondary fermentor for dry hopping. I use a closed transfer system to transfer the conditioned beer into the keg, which I believe is thoroughly purged prior to the fill. I can't think of anything else, and I'm hoping someone can help me figure it out.

This is my first post on the forum. Please forgive any lack of proper etiquette, and please let me know if any other critical information is needed to help me with my problem

Thanks!!
Eric

 

Whats your typical keg pressure? I find my ipa's change quite a bit in the first few weeks. However, I am just for the first time experiencing the same issue as you describe. I filled a small pop top growler for a buddy. He had it 48 hours after I poured. Said it was on the flat side, and aroma was lacking big time. So I went and poured from the tap, I got a real fresh juicy neipa.

My process is real similar sounding to yours. I wonder is it's ingredient based? I have not had this issue before this batch, but used some grains I have not used before. Also made water adjustments I had not made before.

Is this new issue to just this batch for you?

 

This is not a new issue with this batch. I'm trying to get the NEIPA down as well.

Kept it simple this time, primarily 2 row, a very small amount of caravienne, some late boil corn sugar, single hopped mostly late boil and knockout with galaxy hops. Wyeast 1318. Tried to keep mash pH low around 5.2-5.3, which did require phosphoric acid in addition to the CaCl, Gypsum, and a small amount of Epsom. I do dilute with distilled water. Anyways, I don't think it's a water chemistry issue as I have used straight up filtered water and had the same problem.

My keg pressure is around 10-12 psi.

 

Do you dry hop during active fermentation? Do you dry hop once or twice? What is your process for purging your kegs of O2?

 

I dry hop close to the end of primary fermentation, when the bubbling from the blowoff is almost done. My hope is that the very little bit of time it's uncovered and introducing oxygen is removed by the remaining fermentation. I dry hop only once. If ever I want to "double dry hop," I double the amount of hops, but I do not expose the beer twice.

For purging my kegs, I usually do double duty by also sanitizing it. I fill it with a starsan mixture and then push it out with CO2. After it's all out, I pressurize and release a few times. I sometimes have gotten lazy and not made and filled a full 5 gallon mixture of starsan to do this, but if I don't, I usually pressurize and release with CO2 many more times just to have some level of confidence of purging.

Also, when I fill the keg after purging, I push the beer through the beer end of the keg and attach a spunding valve on the other side so other than the initial tiny amount of air in the hose connecting the fermentor to the keg, the beer is not exposed to any other source of oxygen as the gas in the keg displaced by beer is pushed one way through the spunding valve.

 

That all sounds good to me. Filling the keg with starsan and then purging with CO2 is the best method I know of. Dry hopping while yeast is active should allow the yeast to "eat" any oxygen that may be introduced.

You can get that bit if air out of the line before you transfer to the keg by hooking the line up to the quick disconnect and then manually depressing the pin in the disconnect until the liquid starts flowing out of it. Just have a container there to catch the bit of liquid. Then there is no air in the line and you just attach the disconnect to the keg to begin the transfer. I'm not sure how much damage that small amount of air could do, but this is the most oxidation prone style of beer as far as I know.

 

Thanks for the tip. I will definitely remove the air from the transfer hose this next time around!

I actually think this makes a lot of sense and could be plausible as the issue! Since I fill the keg via the liquid line, the beer and presumably the oxygen introduced in the hose will end up close to the top of the filled keg. When the keg is initially tapped, the very bottom liquid is likely the least oxidized. Once that's been poured away, the beer may reach the oxidized stuff. I really appreciate the advice.

 

Can you see bubbles in your beer lines when you pour? Does it pour slightly frothy too? You could have air being sucked in from a hole in the line, a jubilee clip not tight enough, damaged QD (easily done and difficult to spot), damaged rubber on the beer out or dip tube?

If it was oxidation during transfer then youd taste it on your first pour. I had a slightly damaged QD that was causing the beer to pour really heady but tasted flat, after some tracking down (changed a few things on my set up before hand), changed the QD and bish bash bosh

 

I don't think I've noticed any bubbles, but I'll pay more attention next time I pour. I'll double check all of these, thanks! I don't use any quick disconnects, but certainly am not above some connection having an issue. I can, however, definitely say the first pour and subsequent pours on other days taste different. I typically am excited the day I tap the keg as it tastes good and usually will have drank 2-3 beers worth not including any I pour for other people.