Malty flavours fading

[Tricky Dicky]

I recently brewed a California Common and kegged it as normal. I started drinking it after a week in the keg and it tasted great, a nice caramel/toffee flavour up front with a hoppy mildly bitter finish, a really nice drop. Thing is a couple of days later and the malty /toffee flavour has almost disappeared, is this normal?

 

[Jack of all biers]

Likely oxidation. Did your hoppy aroma/flavour also mellow?

Oxidation can quickly remove aromas/flavours before any of the 'typically known tell tail signs kick in (cardboard flavours etc). Loss of aroma/flavour is an early warning sign. There can be many causes going back as far as malting, but transfers post ferment are the most risky and likely causes of quick oxidation. Making sure no splashing or sucking of air into pipe joints is a start. Purging kegs properly (see http://www.lowoxygenbrewing.com/bre...rging-transferring-stabilizing-finished-beer/ ) is another one that is often not thought about. A flavour loss in a couple of days indicates to me that you may not have purged your keg thoroughly and/or transferred with some splashing/sucking of air. The lowoxygen site has a fairly thorough run down of the hows and whatfors as well as prevention methods.

For this beer, keep it cold and drink it reasonably quickly. If your current process eliminates (or at least best you can) O2 from kegging, go back through your steps and think if anything was done differently that might cause it (used a different maltsters malts, used old out of date/old malt as a couple of examples).

 

[Tricky Dicky]

Thanks JOAB, reading through some of the info on the link you provided, would it be a good idea to prime the keg with some sugar after the fermented beer has been transferred to the keg, as apparently further action/fermentation by the residual yeast will consume any oxygen and also create co2. Once some pressure has built up in the keg by this priming it could then be hooked up to the co2 gas bottle as per normal and then chilled?

 

[keine_ahnung]

A week after kegging it tasted great, then a couple of days later completely oxidised....?
Sorry...but that logic does not add up

 

[fdsaasdf]

This doesn't sound like oxidisation to me - if the beer hasn't lost carbonation in the keg then I can't see how it's oxidising there.

At a guess, it sounds like possibly the keg partially froze and you were drinking concentrate for a while, and now the re-diluted beer appears to be less flavoursome by comparison.

 

[keine_ahnung]

Or it took a week to cool down
and now its finally down at 0.5°C and just doesn't seem as malty. haha

 

[pcmfisher]

If it last long enough, it will start to get better again towards the end. Mine do, and have the same symptoms earlier on.

 

[Tricky Dicky]

This doesn't sound like oxidisation to me - if the beer hasn't lost carbonation in the keg then I can't see how it's oxidising there.

At a guess, it sounds like possibly the keg partially froze and you were drinking concentrate for a while, and now the re-diluted beer appears to be less flavoursome by comparison.

The keg is in a temperature controlled serving fridge and is sat well away from the cooling panel inside the fridge so I doubt very much if it partially froze.

 

[Tricky Dicky]

Or it took a week to cool down
and now its finally down at 0.5°C and just doesn't seem as malty. haha

The keg is in a temperature controlled serving fridge so both samples tasted were at approx 10c.

 

[Jack of all biers]

Thanks JOAB, reading through some of the info on the link you provided, would it be a good idea to prime the keg with some sugar after the fermented beer has been transferred to the keg, as apparently further action/fermentation by the residual yeast will consume any oxygen and also create co2. Once some pressure has built up in the keg by this priming it could then be hooked up to the co2 gas bottle as per normal and then chilled?

You can pressurise your keg by priming (the same sugar/dex quantity as bulk priming for bottles) and leave for a couple of weeks before chilling. This should mean you don't need to hook it up to your CO2 bottle to carbonate, as it should already be carbonated (saving gas at the same time). Your keg will have heaps more trub (first two to four schooners will be murky), but I think of the extra vitamins and minerals I get by drinking this so don't mind (when I do it, which is rare). You can't guarantee that the yeast will consume all the oxygen in the head space/what was absorbed by transfer (method depending), so a good thorough purge of the headspace is still called for IMO (read the bit about purging kegs and ppb O2 in the lowdo website).

 

[Jack of all biers]

A week after kegging it tasted great, then a couple of days later completely oxidised....?
Sorry...but that logic does not add up

Not what I said. I said oxidation is the LIKELY issue. It could be something else, hence the question about whether the hop aroma/flavour had also been effected. Oxidation's where I'd look first, as I have noticed similar drop in flavour/aroma in my first kegging experiences. I would say 'completely oxidised' is not the same as the beer losing its flavour and aromas, which to me could indicate the first stages of oxidation, which takes more time to become 'completely oxidised' (ie sherry/cardboard flavours/aromas).

 

[Tricky Dicky]

I'm just about to naturally carb a 19L keg of California Common which was fermented at 16c. The keg will be in the same fridge as a fermentor which needs a temperature of around 20c for the brew that's in there. So the question is, is it ok to naturally carb a keg at 20c that was fermented at 16c?

 

[wide eyed and legless]

You can but need to cool to a temp to get the co2 dissolved into beer.
https://www.kegerators.com/carbonation-table/

 

[Tricky Dicky]

I've used that chart when I am carbonating via a c02 bottle but I assumed the lower temperatures would kill the residual yeast and natural carbonation would not occur?

 

[wide eyed and legless]

Heat kills yeast not cold

 

[Tricky Dicky]

Ah OK, so if I naturally carbonate at 20c in my fermentation fridge and I'm aiming for 2.4 volumes of c02 then according to my reference book for 19L I'll need 60g of sugar?

 

[labels]

I've had some similar experiences, not exactly the same but I do store my beer kegs at near frozen temps. This will cause stratification - with different compounds forming layers in the keg, especially if they have been stored for a few weeks. I simply gently invert the kegs once and it fixes the problem

 

[Tricky Dicky]

Just started drinking a second batch of California Common (same recipe as last time) from the keg after natural carbonation. It had two weeks of carbonating naturally and was ready to drink this weekend. The carbonation itself is great, I like the smoothness and tiny bubbles and no metallic taste that I think bottle co2 brings. However the malty taste is hardly noticeable,the hoppy finish seems stronger than the last batch and it's still a nice drop but any ideas why I am still short on malty flavours?

 

[captain crumpet]

Just started drinking a second batch of California Common (same recipe as last time) from the keg after natural carbonation. It had two weeks of carbonating naturally and was ready to drink this weekend. The carbonation itself is great, I like the smoothness and tiny bubbles and no metallic taste that I think bottle co2 brings. However the malty taste is hardly noticeable,the hoppy finish seems stronger than the last batch and it's still a nice drop but any ideas why I am still short on malty flavours?

you could start by mentioning the recipe and a bit on your process

 

[Tricky Dicky]

you could start by mentioning the recipe and a bit on your process

2.19 kg Pale Malt, Maris Otter (5.9 EBC) Grain 1 66.4 % 1.43 L
0.17 kg Crystal, Medium (Simpsons) (178.5 EBC) Grain 2 5.2 % 0.11 L
0.14 kg Amber Malt (43.3 EBC) Grain 3 4.2 % 0.09 L
0.80 kg DME Sparklinf Amber (Briess) [Boil] (20.7 EBC) Dry Extract 4 24.2 % 0.51 L
40.00 g Hallertauer [5.80 %] - Boil 60.0 min Hop 5 31.0 IBUs -
30.23 g Hallertauer [5.80 %] - Boil 15.0 min Hop 6 11.6 IBUs -
30.23 g Hallertauer [5.80 %] - Steep/Whirlpool 30.0 min, 79.0 C Hop 7 3.8 IBUs -
1.0 pkg San Francisco Lager (White Labs #WLP810)
Irish Moss @15 mins

I have a small set up so mash 2.5kg of grains BIAB and make up the difference for the MO required in the all grain recipe with DME added at the start of the boil.Mashed at 66C 60 mins. Mash out 75c 10 mins. Boiled 60 mins. Final volume in the keg was 18L. OG 1042 FG 1012.Naturally carbonated with 52g raw sugar in cup of boiling water for 2 weeks @ 20c temp controlled. Primary fermentation 20c temp controlled for 2 weeks.

Any observations are most welcome as to why malty taste is not present but identical recipe had nice malty forward taste which faded see OP.