Sickly sweet taste after kegging

[nacnud]

Hi all. I have been brewing for the best part of a decade now but over the last couple of years I have brewed very few beers that I've enjoyed. The problem is a strong sweetness that comes on after kegging or bottling in almost all of my brews. The beer tastes great at the end of fermentation but over the next couple of weeks it develops this thick sweetness that makes it pretty undrinkable.

I've tried everything I can think of to get rid of it. I initially thought it may be diacetyl but there is no sign of it immediately after fermentation and I have been meticulous with my sanitisation so what ever it is seems to be developing at 4 degrees in the keg. I have simplified my brewing down to store bought AG recipes and have tried half bottling and half kegging a brew to see if it's something in the keg or lines but both came out the same. All styles have it, though it's more noticeable in the lighter styles.

After a bit of googling I have found a couple of people describing similar issues but no real explanation. So any suggestions are welcome.

It's really getting me down because I love brewing but I don't know how many more disappointments I can take before I give up entirely.

I brew AG, esky mash tun but have also done BIAB with the same issue. Fermentation is temperature controlled, usually 18 to 20 degrees for an ale and then cold crashed. Straight from primary to 19L kegs after about 2 to 3 weeks usually. Always hitting my FGs. Always tastes good at kegging.

 

[kadmium]

What do you wash your kegs with?

How long after kegging does the flavour develop?

What do you use to sanitise?

Do you take your kegs apart and thoroughly clean out the posts, threads, gaskets etc?

Have you replaced all the orings etc on the kegs?

Have you checked all disconnects including gas and liquid? Its possible you got some suck back into a gas QD and have an infection?

Have you changed your fermenter?

What do you transfer with?

It sounds to me like an infection, its possible that if you use starsan only you may have a resistant bug, perhaps give everything a really good PBW soak and then sanitise with idophor.

Not having a go or anything, just trying to maybe jog your memory or provide some avenues to chase down?

 

[kadmium]

Hi all. I have been brewing for the best part of a decade now but over the last couple of years I have brewed very few beers that I've enjoyed. The problem is a strong sweetness that comes on after kegging or bottling in almost all of my brews. The beer tastes great at the end of fermentation but over the next couple of weeks it develops this thick sweetness that makes it pretty undrinkable.

I've tried everything I can think of to get rid of it. I initially thought it may be diacetyl but there is no sign of it immediately after fermentation and I have been meticulous with my sanitisation so what ever it is seems to be developing at 4 degrees in the keg. I have simplified my brewing down to store bought AG recipes and have tried half bottling and half kegging a brew to see if it's something in the keg or lines but both came out the same. All styles have it, though it's more noticeable in the lighter styles.

After a bit of googling I have found a couple of people describing similar issues but no real explanation. So any suggestions are welcome.

It's really getting me down because I love brewing but I don't know how many more disappointments I can take before I give up entirely.

I brew AG, esky mash tun but have also done BIAB with the same issue. Fermentation is temperature controlled, usually 18 to 20 degrees for an ale and then cold crashed. Straight from primary to 19L kegs after about 2 to 3 weeks usually. Always hitting my FGs. Always tastes good at kegging.

Just re read and saw its bottles too. It could be from a soap residue depending on what you wash with, or an infected transfer tube or fermenter?

 

[nacnud]

HI Kadmuim,

I use Sodium Metabisulphate for kegs and lines, pull the posts off , tubes out and soak the lot each time. I sanitise everything else with Sodium percarbonate (no rinse).

I transfer with silicon tube straight from fermenter to keg. It also gets a soak in no rinse steriliser. The only source I can think of is the tap on the fermenter, which is exposed until transfer but I usually give it a squirt of no rinse 10 mins before transfer. haven't replaced rings etc but as you say, bottles have the same issue.

The taste comes on as soon as it's carb'd but gets worse over a few weeks.

I haven't had a new fermenter in a few years so that's my next plan.

Thanks for the help.

 

[kadmium]

Hmmmm. Perhaps there is something living in the fermenter.

You say as soon as carbed. Same as kegs? Or does it take a week or two?

Once it peaks, does it go away after a while or persist even after conditioning for weeks or months?

Do you take the tap apart, unscrewed from the fermenter and thoroughly clean it internally?

Sodium perc is usually a cleaner and sodium met (kmeta) can be used as a no rinse. Do you have them mixed up? I know sodium perc can theoretically be used but I think its perc for cleaning kmet for sanitising? Again not having a dig just trying to help you nail it down.

Sometimes, an infection can be super hard to track down. You may need to ditch the fermenter and get a new one.

 

[nacnud]

Yeah I'll try a new fermenter next time and some different sanitiser.

You're right, I did have my sterilisers mixed up. What I'm using is the local homebrews brand, just labelled No Rinse Steriliser (Sodium Percarbonate) and Keg and Line Cleaner (Oxygen bleach and sanitiser).

Kegs are sweet by the time they carb (about a week). It doesn't go away, if anything it only gets worse over weeks and months.

 

[kadmium]

Hmmmm. Interesting. Someone with more experience hopefully chimes in with perhaps what exactly is causing it, but if FG is hit I'm thinking an infection as opposed to under attenuating.

 

[razz]

Yeah I'll try a new fermenter next time and some different sanitiser.

You're right, I did have my sterilisers mixed up. What I'm using is the local homebrews brand, just labelled No Rinse Steriliser (Sodium Percarbonate) and Keg and Line Cleaner (Oxygen bleach and sanitiser).

Kegs are sweet by the time they carb (about a week). It doesn't go away, if anything it only gets worse over weeks and months.

Where are you located Duncan? I think you need to get someone with some experience to sample your beer. Local brew shop owner or local brew club members.

 

[nacnud]

I'm in Perth. Yeah, maybe I should take a bottle into the brew shop.

If it's an infection, wouldn't it be noticeable immediately after fermentation? Somehow it's happening under CO2 and at 4 degrees...

 

[razz]

Not sure about that. If you had a ****** tap in your fermenter then it could be from that but that should be evident at any temp. What fermenter are you using Duncan?

 

[TwoCrows]

https://learn.kegerator.com/off-flavors-in-beer/

 

[MHB]

Could be infection, there are a couple of other possibilities.
Can you give us your OG and FG from your last brew, type of yeast, was it a fresh yeast or recultured...
Mark

 

[nacnud]

I'm just using a 30ish L plastic fermenter with an airlock and screw in tap. Fermenting in a temperature controlled fridge.
Last brew was an IPA. Went from 1.062 to 1.008 over a couple of weeks. 2x US-05 rehydrated in 2 cups of room temp water. Pitched at and set to 19 degrees. Was bubbling away within 18 hours and had gone quiet by day 7. Cold crashed for a couple of days before kegging. Tasted good at the time. A week later I could detect the sweetness coming in. A couple of weeks after that it's like someone's dumped a tin of golden syrup in there.

 

[Nickedoff]

Break in the space-time continuum causing your beer to un-ferment?

 

[MHB]

Well you're getting very good attenuation which rules out a couple of obvious mash related possibilities.
Which does sort of point back at infection, always good to rule out options.
Might be a good time to invest in a replacement of everything downstream of the kettle that is made of plastic.
If you no chill, replace the cube, fermenter, all the hoses... the lot. Make sure there isn't a seat of infection in the kettle tap, there are some bugs that can survive pretty extreme conditions.
Clean the inside of the fermentation fridge with a strong bleach solution, give everything an uber clean and cross everything.

Might even be worth going ang getting a wort kit or even a cheap K&K brew and ferment that in the new gear, will prove the problem is fixed. or at least eliminate everything on the cold side.
Persistent infections can be real heart breakers, sometimes its something so small, seen an old spoon with a crack in it that cost dozens of brews, a bit of crud in a ball valve that smelt like blue chees. Worth noting that the number one cause of infections in commercial breweries is the heat exchanger, number two is flexible hoses, always assume the inside is in worse condition than the outside
Lots of luck just be ridiculously thorough.
Mark

 

[S.E]

Might even be worth going ang getting a wort kit or even a cheap K&K brew and ferment that in the new gear, will prove the problem is fixed. or at least eliminate everything on the cold side.

I would do that first but do it in the old gear not new, fermenter, keg etc first before replacing everything. If all good then look at chiller/cube and hoses used prior to fermenter. If it turns out bad then look at fermenter etc.

 

[nacnud]

Thats a good idea. I'll give averything a major clean with a different steriliser and then try a coopers kit. If that goes bad then it'll be new fermenter, hoses etc and another coopers kit.

Thanks for your advice everyone.

 

[chookherder]

Just another voice in the mix here as I had similar experience for about a year, in the end it was my heavy handed amounts of Light Crystal in the recipes. The sickly sweet caramel toffee notes keep creeping up and up slowly but surely. I don't even remember how I got into using so much, whether it was a recipe I saw and extrapolated or just trying to simplify to less types of grain in my recipes, but sure enough I got right out there on the extremities of drinkable. And it was easy to do because we would normally drink all the beer before it was 7 days old, before the sweetness really started to creep in. Give it 4wks and it was a talking point, give it 8wks and it was a toffee beer.

FYI I was using about 500g Gladfield Light Crystal in a 50L batch, and this was way too much. Now I'm down to 200g and happy. There was even one brew I found when I look back (a IIPA with 2kg and 23kg Pale Malt) that after 5mnths was so sickly sweet it was undrinkable.

Could be completely off-base but your experience sounded similar.

Cheeers,
Ben

 

[nacnud]

Thanks Ben, I had wondered if that was my issue. That's why I went to using off the shelf grain bills. Didn't solve my problem unfortunately. I think it must be infection. I just need to work out where it's coming from.

Cheers

 

[S.E]

Break in the space-time continuum causing your beer to un-ferment?

That was also my first thought. Easy enough to test with a hydro sample and see if FG has returned to OG.