Diacetyl

[phantom]

After 5 and a half years of making beer(please note chiller,I didn,t say brewing as i,ve never progressed past extracts) .I have only experienced diacetyl twice in my own beers and put it down to temperature.Recently i noticed it in a coopers pale ale on tap in Adelaide and was at a loss to describe why to a fellow beer drinker.He said it tasted weird,and i told him it was diacety ."What,s that he asked?" <_< .
Could some of you more learned and experienced "brewers" explain the causes and cures eg:diacetyl rest etc......
:blink:

Let the input flow and replace my ignorance with Knowledge,Phantom

 

[Sean]

You make it sound like diacetyl is always a fault - it's a legitimate flavour in many beer styles.

 

[Gulf Brewery]

Hi Phantom

Diacetyl is a product of fermentation or in some cases an infection. It can be cleared by a combination of the yeast and increasing the temperature of the wort.

Cheers

 

[JasonY]

I brewed an ale at xmas that developed a nice dyacetyl tang I believe it was cased by a combination of me racking it early and taking out of the fridge to make way for xmas foods .... the temp never got that warm though (22 ish)

i took it out of the fridge and skimmed some yeast from the krausen of my next batch and left it in the keg at room temp for 2 weeks. Diacetyl is now all cleaned up and the beer is much improved.

 

[Gulf Brewery]

JasonY

Diacetyl rests for lagers are usually performed at 15/16C. A lot of English ales have and need diacetyl in them for their flavours.

Cheers
Pedro

 

[JasonY]

I didn't like the dyacetly in this one, a few ppl tried it and seemed to agree (except Goat who liked it as is). I skimmed some Munich lager to use to remove the diacetyl and it did an excellent job although it has chnaged the flavour profile significantly. It now tastes like a coopers pale rather than the english style I was after.

This was my first effort using 1098 British Ale, wasnt expecting as much dyacetyl as I ended up with. It was interesting to actually remove the dyacetyl, be it right or wrong for the style.

 

[Guest Lurker]

I tasted that ale and there was way more than a contribution to the flavour, it was the dominant flavour. Great news that you were able to clean it up. Interesting that it was 1098, I just did an ESB with that yeast, will go and have a careful taste.

 

[fergi]

hi guys
well i have made up a grumpys german lager which i have in the fridge at about 12/14 deg,i am trying to keep it around about 12 deg but as i am relying on a timer to switch the fridge on and off i havent quite got it under control yet,anyway when it finishes the fermentation in primary should i give it one of those dyacetly rest thingies at a warmer temp for a couple of days before i put into my secondry at about 4 deg for a bout a month,if so what temp and how long do you recomend the D rest before i secondry,i am using w 34/70 yeast
cheers
fergi

 

[sosman]

I haven't done one for a while but 48 hours at 16C rings a bell. If you don't notice any diacetyl in a sample you can probably skip it.

 

[fergi]

thanks sosman
but i have no idea what a D tastes like so do you think i should just give it the D rest anyway
cheers
fergi

 

[sosman]

thanks sosman
but i have no idea what a D tastes like so do you think i should just give it the D rest anyway

Probably won't hurt.

OTOH if you don't know what it tastes like then there is one way to learn.

 

[big d]

tastes like butterscotch fergi.only ever tasted it once and was very pronounced to my palate.tasted it at an adelaide micro of all places.cant remember if it was a fault or meant to be there.never did get around to asking h34r: if it was purpose done.

cheers
big d

 

[mikem108]

John Palmers notes on whats different when fermenting lager is very informative it mentions in detail when to do the diacetyl rest.
Wish I'd read it before doing my last beer...
http://www.howtobrew.com/section1/chapter10.html

 

[thehipone]

I love the flavor in the right context. SOmething like Old speckled hen, mmmmm, just enought butterscotch and toffee flavors.

 

[Guest Lurker]

Hey JasonY. My ESB with 1098 is nearly gassed up and so I tried a bottle, and now that I taste it carefully, there is some diacetyl there, which I think, not that I know, is to style for an ESB, its not nearly as much as there was in yours, but its noticeable. I gave mine 16 days in primary which should have removed a fair amount.

But I am tasting more diacetyl than I ever did with 1968 which is supposed to be a big producer. Theres no mention of diacetyl on the wyeast site (see below) whereas they specifically warn about it with 1968.

Anyone else found 1098 to do this?


From the Wyeast site
1098 British Ale Yeast. The original dried yeast from Whitbread. Produces beers with a clean neutral finish allowing malt and hop character to dominate. Ferments dry & crisp, slightly tart, fruity and well-balanced. Ferments well down to 65F (18 C). Flocculation - medium; apparent attenuation 73-75%. (64-72 F, 18-22 C)

 

[JasonY]

Well in some ways thet makes me feel better that I ended up with a fair bit! I guess this yeast may bear a bit of watching with diactyl, I also didn't expect it to be an issue given the description.

Sounds like your ESB's are fine, I guess conditioning may even clear it up some more over time.

I wonder if others have had similar experiences with this one.

 

[sluggerdog]

I am doing a lager at the moment and I have it resting now.

My probem is I can only keep mine at about 22-24c at the moment so should I shorten the time for the rest to maybe 1.5 days? (instead of 3 days)

I have had it now which slowly rose from 10-12C to 24C over 24 hours.

 

[THE DRUNK ARAB]

I recently brewed an IPA using Wyeast 1056. It started at 1068 and finished at 1013. I racked it off after 2 weeks onto some Cascade pellets. It was dry hopped for 1 week then bottled. It has been in the bottle for 1 week and I cracked one last night and there is definately some diacetyl present. Does this normally dissapear after a while? And does 1056 normally give off diacetyl? It was an XL smack pack and I made a huge starter for it!
On reflection I should have left the beer in primary for one more week as it was a biggish beer.

C&B
TDA

 

[Darren]

TDA
Yep, 1056 does give off diacetyl. My experience is that it usually fades away after a couple of weeks. Bottle conditioning should help to clear it up too.
cheers
Darren

 

[THE DRUNK ARAB]

Thanks for that Darren.

C&B
TDA