Beer always changes flavor within a day of kegging

[bradleypariah]

Dudes. I'm at my wit's end. This is my umpteenth homebrew that has acquired an off-flavor within 24 hours of kegging. Naturally, I thought my keg must be contaminated. Nope. I filled my keg at a local microbrewery a couple weeks ago. It tasted fine for weeks. It can't be the keg or the serving line.

My beers, prior to kegging, taste like a hop-haven of happiness with great aroma. I literally get so excited, becasuse I think, "This is going to be the time that I make the best beer I have ever tasted." Within a single day of kegging, they always taste like a band aid with zero aroma whatsoever. EVERY_SINGLE_TIME. For years! I can't believe I haven't given up home brewing.

I was convinced I was aerating my beer during transfer, so I bought carboy caps, and used CO2 to purge the top of the carboy, allowing the siphon to pour CO2 into my corny keg. The siphon and hose were of course sanitized with StarSan. After waiting long enough for the carboy and hose lines to be full of CO2, and there to be a bed of CO2 in the keg, I pressed the siphon into the beer in the carboy. The line had a couple bubbles in it for a few seconds, and despite being positive it was just CO2 in the line, I lifted the hose into the air until all the gas had escaped, and dropped the liquid-filled line back into the keg. The line stayed full of liquid until the transfer was complete.

After transferring, I added 30psi of CO2 to the keg to get a good seal, waited a minute or so, then purged the keg a few times until the PSI dropped to about 15, allowing all the oxygen (if any) to get out.

I totally realize I am asking for guesses and speculation, but I am SICK of wasting five gallons of beer every mother effing time I keg. This is so frustrating! Does anyone have any idea what is going on? Have any of you ever experienced this and gotten past it?

 

[day_trippr]

Where do you get your brewing water?

 

[bradleypariah]

From the tap. We live in an Oregon town that has water with a lot of gypsum in it. It doesn't smell like chlorine and it tastes good. I had the problem before we moved to this town as well. I've been here for a year.

Here's our water report:
http://www.mtangelor.org/sites/defa...eral/page/1354/mt_angelcity_2015_revision.pdf

 

[day_trippr]

"Band Aid" is a classic chlorine/chloramine symptom. You may have moved from one town that treats its water to another - hardly uncommon, you'd be hard-pressed to find any public or large private water systems in my state that doesn't use chlorine or chloramine.

I got bit by the Band-Aid very early in my brewing life as the private water company serving my area used chloramine - which was actually a surprise to me - it wasn't obvious to my senses. When I learned what that meant, I would either pre-treat with Campden tabs or buy RO water. Eventually the water company went bankrupt and we had to drill a well, which solved that problem for good

So I wouldn't discount that as the root cause of the problem just because you don't smell chlorine.
It's the easiest explanation and one of the easiest brewing issues to fix.

btw, if for some reason you suspect your kegs/dispensing system, bottle a six pack of your next batch...

Cheers!

 

[flars]

Use Campden in any tap water associated with brewing your beer, even in your sanitizer. Just because tap water tastes good and doesn't smell like it has been treated it still may not be good for brewing beer. Band aid taste is indicative of chlorine or chloramine content in the water.

 

[leesmith]

From the tap. We live in an Oregon town that has water with a lot of gypsum in it. It doesn't smell like chlorine and it tastes good. I had the problem before we moved to this town as well. I've been here for a year.

Here's our water report:
http://www.mtangelor.org/sites/defa...eral/page/1354/mt_angelcity_2015_revision.pdf

I agree with what previous posters have said.

http://www.mtangelor.org/general/page/public-works

Second paragraph on this page states they use a chlorination system.

Use either bottled water or Camden tablets or RO water.

You can probably get away with washing and rinsing with your water untreated but no more than that.

This page explains how to mix Starsan in a gallon jug of distilled water. Pour some of that in a spray bottle and use that to sanitize after washing.

http://www.homebrewfinds.com/2011/09/tip-using-star-san-in-spray-bottle.html

Do a batch without your water and see if there is a difference.

My town water is treated and I had some band aid flavors early on. I changed to Poland Spring and never had that problem again. I just installed an RO system so I don't have to mess with buying jugs of water for every brew. I would have treated my water with Campden tablets but the alkalinity was so high that the R.A. would require too much acid to adjust.

 

[str1p3s]

What's odd is that you say it tastes good before kegging. I had a chlorine problem when first started and it tasted nasty from the first sample. Then I bottled it and it just tasted like carbonated nastiness.

Every time I brew, I have to make sure that I actually like the beer and that I'm not trying to convince myself that I like it because I want it to turn out good. Are you sure the sample tastes good or are you in denial? It took me a while to admit to myself that those first few brews were bad. And they were REALLY bad.

A problem with your keg or kegging process would account for it tasting fine going in but changing a day later. But it seems like you've eliminated that.

 

[SGTSparty]

I'm not a water chemistry person so I'm not going comment on those theories but using bottled water once and seeing if it makes a difference seems like a pretty easy experiment. That said if your samples are tasting good before the keg then I'd say maybe its something involved w/ your transfer equipment? Maybe you have something in your siphon or tubing that's imparting off flavors?

 

[bradleypariah]

What's odd is that you say it tastes good before kegging. ... Are you sure the sample tastes good or are you in denial?

See, that's what's got me stuck. My wife knows my struggles. I snagged a bit of beer with a thief earlier this week, and it was hoppy to high heaven.
The day before yesterday, right after putting it in the keg, I poured some out the tap, and it had a beautiful hop aroma. I let the wife smell it, and she agreed that is smelled like a commercial IPA.
Last night, the beer was of course still flat (the keg is just resting at 15psi for now), and I snagged a little sample again. It's been in there for 24 hours. No hop aroma whatsoever remains, and the flavor is lifeless and stale.

It can't be oxygen, because I transferred with CO2.

I am so unbelievably confused. Does StarSan take days to dissipate? Should I not be refrigerating directly after kegging? Perhaps my yeast combat what little chlorine is left after the boil, but when I introduce the beer to a keg that has been sanitized with un-boiled water, the tiny bit of chlorine is spoiling the beer??

I'm going to buy campden tablets, and I think I'm going to make a bucket of StarSan water with campden water. I just don't understand why the beer is waiting until 24 hours after I keg it to show its true colors. I'm wondering if I have two problems, not just one.

Maybe you have something in your siphon or tubing that's imparting off flavors?

I pump my siphon with hot water and StarSan every single time I use it, before and after. The tube looks clean. I have five gallons in secondary in the basement right now, and it tastes fine. I'm going to replace the tube just to be safe. Despite my off-flavors, I'm still drinking this keg. So, it'll be a couple weeks until I transfer. If the good tasting beer goes bad after being transferred with a new hose, we'll know to look more deeply into the water.

Thanks everyone for your input. If anyone else has further insight, it is still welcome of course. Thank you guys so much.

 

[leesmith]

When a hoppy beer is first kegged and still warm there is still a lot of hop oils and other stuff in suspension...once chilled...essentially cold crashed....some of those flavors drop out...they are probably masking your problem before the keg has completely chilled and stuff has dropped out.

Can you post a recipe? Until I increased my hopping rates the hops dropped out after chilling and the beers were lack luster as far as hop aroma and flavor.

Chlorine needs to be removed before brewing with the water. It will cause problems.

Starsan will not harm your beer if made with decent water.

 

[Revvy]

See, that's what's got me stuck. My wife knows my struggles. I snagged a bit of beer with a thief earlier this week, and it was hoppy to high heaven.
The day before yesterday, right after putting it in the keg, I poured some out the tap, and it had a beautiful hop aroma. I let the wife smell it, and she agreed that is smelled like a commercial IPA.
Last night, the beer was of course still flat (the keg is just resting at 15psi for now), and I snagged a little sample again. It's been in there for 24 hours. No hop aroma whatsoever remains, and the flavor is lifeless and stale.

It can't be oxygen, because I transferred with CO2.

I am so unbelievably confused. Does StarSan take days to dissipate? Should I not be refrigerating directly after kegging? Perhaps my yeast combat what little chlorine is left after the boil, but when I introduce the beer to a keg that has been sanitized with un-boiled water, the tiny bit of chlorine is spoiling the beer??

I'm going to buy campden tablets, and I think I'm going to make a bucket of StarSan water with campden water. I just don't understand why the beer is waiting until 24 hours after I keg it to show its true colors. I'm wondering if I have two problems, not just one.



I pump my siphon with hot water and StarSan every single time I use it, before and after. The tube looks clean. I have five gallons in secondary in the basement right now, and it tastes fine. I'm going to replace the tube just to be safe. Despite my off-flavors, I'm still drinking this keg. So, it'll be a couple weeks until I transfer. If the good tasting beer goes bad after being transferred with a new hose, we'll know to look more deeply into the water.

Thanks everyone for your input. If anyone else has further insight, it is still welcome of course. Thank you guys so much.

All this sounds like is you're getting co2 bite from trying the beer too soon, while it's not even carbonated, but has a lot of co2 floating around... The proper name is "Carbonic Bite"

And here's an explanation of what it is...

Especially if you're burst carbing the beer as opposed to letting the keg sit at serving pressure for a week and carb up slowly.

How does it taste in a week when the beer is actually carbed and balanced out?

A lot of flavors and aromas are stripped out initially when chilling and carbing, or masked by excess carbonic acid... but once co2 is in suspension, and the beer is at the right pressure, than everything is lifted.

Maybe rather than tasting the beer after only 24 hours in the keg.. you should wait a few days... you might notice that the only "problem" you're having is impatience.

BTW, my beer tastes bitter and metallicy when I burst carb it and pour a sample 24 hours later... but once it's carbed AND conditioned it tastes like it should.

 

[Revvy]

Brulosopher has some mention of carbonic bite in these articles...

Sparkle and Fizz

From Carboy to Cup, my kegging methods....

 

[bradleypariah]

When a hoppy beer is first kegged and still warm there is still a lot of hop oils and other stuff in suspension...once chilled...essentially cold crashed....some of those flavors drop out...they are probably masking your problem before the keg has completely chilled and stuff has dropped out.

That makes a lot of sense!

Can you post a recipe?

5 gallon batch

Steep at 152° F for 60 minutes:
1 lb 20L
1/2 lb flaked oats
Full disclosure, I'm a bag-squeezer. Beer doesn't taste like tannins, though.

Boil
9 lbs of light LME
2oz Cascade for 60 minutes
2oz Cascade for last 15 minutes

Flame out
2oz Citra, lid on, sit 25 minutes, then chilled with immersion to 75° F
Sloshy pour through strainer/funnel into 5gl carboy.
Cool water top off.
OG was somewhere around 1062
Two packs of San Diego Super Yeast

One week in primary, then rack to new, sanitized carboy, add 2oz Centennial
After two weeks in secondary, added 1 cup of Crater Lake Gin-soaked light oak chips.
Sit on oak chips for five days. CO2 push into keg.

How does it taste in a week when the beer is actually carbed and balanced out? ... Maybe rather than tasting the beer after only 24 hours in the keg.. you should wait a few days... you might notice that the only "problem" you're having is impatience.

That makes a lot of sense as well. The beer often does mellow with time, but it doesn't seem to ever get back to the hoppy level it came from.
Perhaps I need to drop a marble-weighted bag of hops into my keg, and let it pressurize at room temp for a few days before chilling?

 

[dyqik]

When a hoppy beer is first kegged and still warm there is still a lot of hop oils and other stuff in suspension...once chilled...essentially cold crashed....some of those flavors drop out...they are probably masking your problem before the keg has completely chilled and stuff has dropped out.
.

Yes, the one chloramine issue I had (town upped the levels to more than a quarter a Campden tablet per 5 gallons could deal with) got much more noticeable and recognizable on chilling and carbonating the beer. Warm at kegging in a pale ale it was closer to green beer taste. Cold it was obviously wrong.

 

[bradleypariah]

town upped the levels to more than a quarter a Campden tablet per 5 gallons could deal with

What did you do? Switch to bottled, or add more campden?

 

[BigJoeBrew]

I agree with Revvy that it might be carbonic bite. I have had numerous IPAs that I have tried soon after kegging to have the hop flavor diminish, but once carbed up in a week the beers tasted great. Give your CO2 time to do its job, then see if the off flavor is still there, then move on to other reasons it might be.

 

[Revvy]

That makes a lot of sense as well. The beer often does mellow with time, but it doesn't seem to ever get back to the hoppy level it came from.
Perhaps I need to drop a marble-weighted bag of hops into my keg, and let it pressurize at room temp for a few days before chilling?

That's two separate things... the first, which you answered that the beers "mellows with time" proves that you're sampling too soon and dealing with carbonic bite.

The other issue- hops fading... That happens all the time.. hops ALWAYS fade over time. That's just the way it is... You can mitigate it by hopping high initially.... Playing with things like First wort hopping and/or hopping bursting... adding a massive amount of dry hopping.

You can put hops in the keg like you said, but I'm always leery about doing that, throwing something in there that you might have to open the keg and fish out when they become "grassy" with age...

A better option is a "Hops Transducer" or as Dogfish Head, the inventors dubbed it the "Randall The Enamel Animal."

They're really easy to make out of water filter housings...

I have mine mounted inside my keezer, and I actually have it setup to split the beer from a keg- one directly to a tap, and the other running through the randall and to it's own tap.

It's got a quick disconnect so I can remove the randal to clean it, and/or bypass it entirely to have just 4 kegs running.

 

[bradleypariah]

A better option is a "Hops Transducer" or as Dogfish Head, the inventors dubbed it the "Randall The Enamel Animal."

That thing is amazing!! I want one!

 

[dyqik]

What did you do? Switch to bottled, or add more campden?

Add more Campden. I just use a whole tablet in the strike water and another in the sparge water, for a 5.5 gallon batch. The town was dealing with some organic contamination in the water system at the time, but has reduced the chloramine again. But having had one bad batch, I figure it's easier to just add more than get a bad batch again some time.

There's no need to worry about over doing Campden - 1 tablet in 5 gallons is no problem. The LoDO people actually recommend about 1-2 tablets if you preboil strike water to deoxygenate it, as the metabisulfite part of Campden scavenges oxygen that dissolves in after boiling.

 

[day_trippr]

While it's been evident that some folks might confuse carbonic bite with some other off-characters, I'd be surprised that "carbonic bite" and "band-aid" could be confused.
They are quite different tasting defects, with "band-aid" pretty much on its own limb of the defect tree...

Cheers!

 

[Revvy]

While it's been evident that some folks might confuse carbonic bite with some other off-characters, I'd be surprised that "carbonic bite" and "band-aid" could be confused.
They are quite different tasting defects, with "band-aid" pretty much on its own limb of the defect tree...

Cheers!

He says in his last post to me that "The beer mellows with time" if it were a chloramine issue it wouldn't go away....

And I've tasted strong carbonic bite, and I could see how it COULD seem bandaid/rubbery initially, especually since terms like Band-aid, Horse blanket, and actually subjective terms. Not many people have ACTUALLY chewed on a bandaid, or sucked on a horse blanket, yet we use these terms... and many people can't even make the metaphoric leap to even imagine those terms we use. So I'm usually hesitant to take someone's TERMINOLOGY at face value.. one persons band aid could be another's metallic taste- like one person has no problem with cilantro, and to another's palate they describe it as soap... So I often look for other clues... OR past experience with other people posting similar questions.. AND some of what he describe is the same thing that many new keggers start similar threads about... that tends to be carbolic bite...

We're all going to read things into it.. and we're all also going to project out "pet" theories.

But none of us will "Know" unless WE were actually tasting the beer ourselves. We're all just speculating here, based on OUR experiences... One doesn't need to be "snippy" about it.

*shrug*

 

[leesmith]

I agree with day_trippr...
The OP is brewing with and then topping off with cold tap water that's been treated with chlorine and since we don't know the details possibly chlorimine (which doesn't boil off)...

For one batch try bottled water.

 

[bradleypariah]

I'm thinking it's a combination of all of the above.
Beer is hoppy when it's warm and suspended.
Getting it cold drops my hop suspension and exposes the chlorine.
I'm tasting it too quickly after carbonating, so it's got a bite on top of losing it's hop aroma and exposing the bad flavor.
That's actually a train wreck of bad stuff to happen all at once.
I never would have thought of all that without you guys. This is so helpful.

 

[TheMadKing]

Thanks everyone for your input. If anyone else has further insight, it is still welcome of course. Thank you guys so much.

I'm curious about your CO2 source. Where did you buy it? Have you tried swapping your tank out for a fresh one? Are you sure you got relatively pure CO2 ~99.96%?

I don't buy carbonic bite killing hops or causing bandaid flavors, or chlorine manifesting only after kegging.

It either has to do with temperature or your gas.

So I would try cold crashing for a couple days before kegging and see if that kills your flavor pre-keg. If that causes the same issue then it's just stuff dropping out.

If your beer still tastes great, hook up the CO2, if it manifests then you know it's your gas supply.

You could also try carbonating some distilled water with your CO2 and see if it tastes funky afterward.

 

[zgja2]

I have to agree with day tripper as well. i have dealt with this same issue and it can make ya go crazy, especially because I am much more sensitive to it than other people.

I now treat water with camden and filter. same with star san.

 

[bradleypariah]

I'm curious about your CO2 source. Where did you buy it? ... It either has to do with temperature or your gas.

I buy it from AirGas. They supply most of the restaurants in the state. A local brewery owner told me he uses them too. It's a 5lb tank. As I said in the OP, just before this batch, I had my keg filled by a local microbrewery, and while it was carbonated by them, it was on my CO2 for serving for a couple of weeks. No off flavor ever surfaced. Not sure if that rules it out.

 

[dyqik]

I buy it from AirGas. They supply most of the restaurants in the state. A local brewery owner told me he uses them too. It's a 5lb tank. As I said in the OP, just before this batch, I had my keg filled by a local microbrewery, and while it was carbonated by them, it was on my CO2 for serving for a couple of weeks. No off flavor ever surfaced. Not sure if that rules it out.

It at least says that the CO2 isn't horribly bad. But beer carbonated elsewhere will be a lot less sensitive to CO2 contamination. Typically there's about 2 vols of CO2 in solution when carbonated, so that's about the same amount of CO2 added for carbonation as is added when serving a full keg at 15psi (gauge pressure, 30 psi absolute pressure).

 

[helibrewer]

I dry hop in the keg using a SS mesh cylinder, it eliminates a racking step that can introduce problems and allows you to easily swap out for fresh hops on subsequent dry hopping intervals.

Brew a batch using 100% RO with mineral treatment, assess the results.

 

[day_trippr]

He says in his last post to me that "The beer mellows with time" if it were a chloramine issue it wouldn't go away....

It's nearly a lock that brewing with chlorine/chloramine water sans countermeasures will cause a band-aid note.
Otoh, lots of folks burst carb without complaints.

Occam's Razor. If I'm wrong I can live with it

Cheers!

 

[Trail]

Make sure you post back once your next batch is up. Some of us get emotionally invested in "ruined beer" stories.

 

[bradleypariah]

Here's an early update:
The beer is a super clear, ruby red with a lot of character. The recipe is in this thread somewhere.

The beer just started to show signs of proper lacing last night, and a small amount of hop aroma has returned, surprisingly enough.
So, to go from "Wow!", to absolute tasteless, metallic band aid, back to, "Hey! This is pretty good!" took 90 hours.
I drank three glasses (about two pints-worth) last night, and I felt very nice. Perhaps/hopefully tonight it will be even better.

All that said, I am still not completely happy. Although the initial metallic bite is subsiding, and I have accepted my net loss in hoppiness, somehow there is still some kind of off flavor that disappoints me. It's the same one I was complaining about initially, but letting the CO2 settle has somehow unpublicized it. Some kind of astringent "thinness" that's hard to put my finger on is still lingering there, and based on my experience, it is not going to go away. I believe the keg will empty while still showing signs of it. It is preventing my beer from tasting "pro". Perhaps this is the flaw in my water.

So! Early impressions to all your guys' input are that just about EVERYONE was right.

• Dropping the temp forced the yeast to drop out of suspension, along with a lot of flavor-masking hop particles
• Pushing higher-than-serving PSI onto the beer yields a very metallic and chemical flavor between the second and fourth days, possibly over-signaling the beer's less desirable attributes
• Once the CO2 starts to properly absorb, the hop aroma begins to return, but as to be expected, never gets back to the glory aroma of the beer's warmer carboy days
• Too early to tell, but the remaining off flavor might be able to be solved with Campden

I have this full keg to go through, and I have another beer in the basement (unfortunately not treated with Campden either). As soon as I tap that beer in the basement, I'll brew my next batch, which should be within a month, so I'll most likely be able to share my Campden findings within the next six weeks. Thank you all for your time!

 

[oujens]

I might have missed it, but what steps do you take to minimize o2 pickup during transfer? I've finally solved my kegging issues and little did I know I was suffering from oxidation. Even the slightest bit of o2 will diminish your hops. Probably another difference between your commercial keg and home brew.

 

[Trail]

Even the slightest bit of o2...

I have to disagree with you, strenuously.

Loads of very picky people brew beer without going nuts about CO2. Hell, cask ale is actually served by displacing served beer with air, and while oxidation happens, it isn't overnight and oxidation-released off flavors don't improve with time, even a little bit.

An indistinct, thin, "meh"-ness of flavor is a classic symptom of water chemistry problems. Bradleypariah should get labs run and make the appropriate corrections, and I bet you a pair of twelve-ounce "yeast samples" the issue goes away.

 

[casualbrewer]

Although I agree that the water is most likely the culprit, he listed using LME in his recipe. Perhaps he is sensitive to "extract twang". I know I can tell a difference.

 

[oujens]

I have to disagree with you, strenuously.



Loads of very picky people brew beer without going nuts about CO2. Hell, cask ale is actually served by displacing served beer with air, and while oxidation happens, it isn't overnight and oxidation-released off flavors don't improve with time, even a little bit.



An indistinct, thin, "meh"-ness of flavor is a classic symptom of water chemistry problems. Bradleypariah should get labs run and make the appropriate corrections, and I bet you a pair of twelve-ounce "yeast samples" the issue goes away.

I agree it takes time for oxidation to present itself and the OP needs to check water. However, later there is a description of "metallic, no hops" and in my experience has been related to oxidation. Wouldn't hurt to review that process as well.

 

[Ashevillain]

Gonna start throwing darts here... I've heard from someone at a LHBS in VA that beer that gets below freezing can develop metallic flavors... Unsure if this is remotely true or if the flavor is lasting, the guy might have had no idea. I definitely know most beer tastes better at 38 or higher, and I have never really seen the value of crashing to near freezing after several tries vs 36-38.

 

[dyqik]

I have to disagree with you, strenuously.

Loads of very picky people brew beer without going nuts about CO2. Hell, cask ale is actually served by displacing served beer with air, and while oxidation happens, it isn't overnight and oxidation-released off flavors don't improve with time, even a little bit.

Cask beer recipes are formulated for cask serving, and cask beer only lasts a few days in the cask after tapping due to oxidation. Carbonation happens in the cask by secondary fermentation there, so oxygen pickup in transferring is mitigated.

American craft beer recipes are not generally formulated for cask serving. American IPAs in particular are very prone to oxidation.

 

[bradleypariah]

I might have missed it, but what steps do you take to minimize o2 pickup during transfer?

CO2 transfer to keg. I use carboy caps like this one:

I plug my CO2 into the diagonal tube, and I stick my siphon wand into the center tube. I turn on CO2 at about 1 or 2 PSI. At this point, the siphon is sticking out of the beer, so it's just straight CO2 going into the carboy, and making its way through the siphon and tube. The tube end of the siphon is sitting in the sanitized keg, and it reaches the very bottom.

After running CO2 for about five seconds, and I'm pretty sure there's hardly any oxygen left in the carboy or the line, I push the siphon wand down into the beer. I just leave the CO2 on at about 1PSI. I start the wand at about the middle of the carboy, and wait till the beer level gets close, then slowly push it down, inch by inch as the beer level drops. Once the beer is low enough, I can see right through it, and I can see how close the wand is to the yeast cake. I tip the carboy, and push the wand as close as necessary to maximize liquid output, but minimize pickup of waste.

I pull the tube out of the keg, and seal the top. I apply 30PSI to the keg to get a good seal, then start purging in pulses. I keep purging till I've
exhausted all pressure. I then let it fill back up to 15-20 PSI, or whatever pressure I feel like carbonating at.

Any of that sound bad? Thanks for the response.

 

[bradleypariah]

I've heard from someone at a LHBS in VA that beer that gets below freezing can develop metallic flavors... Unsure if this is remotely true or if the flavor is lasting, the guy might have had no idea. I definitely know most beer tastes better at 38 or higher, and I have never really seen the value of crashing to near freezing after several tries vs 36-38.

I don't crash. I transfer to secondary to harvest my primary vessel's yeast, and my beer clears while in secondary. I do closed transfers to secondary using nothing but CO2. Like this:

I'll check the temp of my kegerator.

 

[oujens]

CO2 transfer to keg. I use carboy caps like this one:

I plug my CO2 into the diagonal tube, and I stick my siphon wand into the center tube. I turn on CO2 at about 1 or 2 PSI. At this point, the siphon is sticking out of the beer, so it's just straight CO2 going into the carboy, and making its way through the siphon and tube. The tube end of the siphon is sitting in the sanitized keg, and it reaches the very bottom.

After running CO2 for about five seconds, and I'm pretty sure there's hardly any oxygen left in the carboy or the line, I push the siphon wand down into the beer. I just leave the CO2 on at about 1PSI. I start the wand at about the middle of the carboy, and wait till the beer level gets close, then slowly push it down, inch by inch as the beer level drops. Once the beer is low enough, I can see right through it, and I can see how close the wand is to the yeast cake. I tip the carboy, and push the wand as close as necessary to maximize liquid output, but minimize pickup of waste.

I pull the tube out of the keg, and seal the top. I apply 30PSI to the keg to get a good seal, then start purging in pulses. I keep purging till I've
exhausted all pressure. I then let it fill back up to 15-20 PSI, or whatever pressure I feel like carbonating at.

Any of that sound bad? Thanks for the response.

Are you purging your keg prior to transfer? Without active yeast you could picking up some o2 if the keg is not purged prior to transfer.