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Diacetyl rest for ales

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Quick question on Diacetyl resting. Do brewers think it’s advantageous to do a rest for ales?

Normally I would raise the temps a little towards the end of fermentation to help the yeast clean up, so to speak. However with this last brew I didn’t and I’ve noticed an ever slight Diacetyl taste in this beer. 

 

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I have never experienced it with an ale although I have read that some ale yeast can produce more diacetyl than others.

I figured that I ferment in the D-rest range so if I leave it a few days post fermentation then I am effectively doing a D-rest.

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16 minutes ago, Hairy said:

I figured that I ferment in the D-rest range so if I leave it a few days post fermentation then I am effectively doing a D-rest.

Maybe ive crashed it too early then. 

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Indirectly i do a d rest for every batch. I ferment in the fridge and when its 4 or 5 points away i will take it out into the ambient to finish off and clean up.

Allows you to get another fermenter in the fridge a little earlier.

Edited by Greeny1525229549
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True. About the bottle d rest,

Just got me buggered where this syrupy taste is coming from. Unless the LHBS has put the wrong grains in the mix, which is totally plausible. 

Its only in this beer which is my normal hoppy pale grist. It has carapils in it, and it’s slightly darker than normal. Maybe they put another type of crystal in there. 

Edited by The Captain1525230099

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2 minutes ago, Ben 10 said:

never... but i always raise the temp anyway - same thing?

I guess it is. Gives the yeast a chance to clean up the beer.

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The yeast will clean up regardless of the temp being raised, it's just that raising it speeds it up a bit. 

I always do it but more for the speeding up than diacetyl. I've never once tasted it in either ales or lagers. 

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I did an ale with pilsner malt and skipped the diacetyl rest, I had bad diacetyl. I used m54 yeast and carapils. It was trying to get a brew ready for a comp in wangaratta, I had 24 days, I chose to do 10 days fermentation and 14 days in the bottle.  The beer didn't reach final gravity until day 8 and I chose to cold crash it instead of doing a d rest, I tasted a sample from the keg, didn't sample the FG sample because I was rushing out the door, and it tasted sweet with a buttery smell. I chose not to send in that beer, I didn't want to be THAT beer sample the judges passed around to taste the flaw! I have never had diacetyl but knew what it was from the smell and taste.

I fermented the M54 at 16c, lower than suggested, but I wanted to see what would happen, I expected a cleaner beer, but hindsight is 20/20, as I wanted it done in 10 days I should have fermented at 18c and then raised it to 22c when it hit 1.025ish. As there were a few things wrong with my process I have now decided to follow the suggested temp ranges for yeast and I will always do a diacetyl rest, unless it is a saison or something. 

Live and learn

Norris

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I think I’m going to have to think out a part of my process to work for me. Maybe it’s getting my wife to up the temp after a five  days sitting at 18-19. So then as to do a rest for a couple of days before I get home to dry hop and cold crash. 

 

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Hi Norris.

The yeast strain you have used for this brew is as it says on the packaging, "a unique lager strain". It is the strain used primarily for brewing "Steam" beers. It throws very unique flavours for a lager strain @ typical ale ferment temperatures. I've brewed this type of beer & it is very unique & different to other types of beer.

I admit I haven't fermented it at 16°C to know whether diacetyl would appear, but suspect you are experiencing a sweetness from this strain that you were not expecting, but is somewhat typical of this yeast strain combined with a typical steam beer malt grist. ?

If I were you, I'd go & buy a bottle of a well known brand Steam beer & compare what you taste from that with your brew. You'll know for sure whether it is diacetyl or the yeast, or even perhaps a combo of both by doing that.

It's all good learning moving forward.

Cheers,

Lusty.

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I have never heard a better suggestion! I will pick up some tomorrow.  I would love for it to be my ignorance and not my brewing...but I think both go hand in hand.  You have to know your ingredients and what to expect. I felt pretty comfortable using the yeast but it was my first time using pilsner lme so that kind of led me down the diacetyl route.

Cheers

Norris

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It could well be diacetyl Norris. I'm purely speculating on a sweetness you have encountered unexpectedly that I feel may be due more to the strain of yeast used that you haven't before.

Diacetyl is a very obvious flavour when it is present. Very strong & obvious butterscotch. I've had the misfortune of producing a beer that had it.

Cheers,

Lusty.

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Beware! The Mountain Goat Steam Ale isn’t actually a steam beer.

You will probably have to buy a US beer, such as Anchor Steam Beer.

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Keeping an ale at a stable temp is supposedly good enough but, because I bottle carbonate, I always increase the temp by a couple degrees, for a couple of days. It is not out of concern about diacetyl, but to make sure it has truly reached final gravity. Amounts to the same thing as a D-rest though.

Cheers,

Christina.

Edited by ChristinaS1
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Steam beer? Yuck. I always thought I disliked it because they contain Northern Brewer hops, but maybe it is the yeast / fermentation temp?

Cheers,

Christina.

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I tried an Anchor steam beer somewhere a few years ago and didn't really like it that much. But it's good to try different things to figure out what you like and don't like.

Keeping a lager at ferment temps it will eventually clean up any diacetyl as well; the temp rise is just to make happen faster.

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After reading all this I believe I may have just not left it long enough before CC.

Either that or infection. 

If anyone remembers I had a beer volcano out the top of my FV. I’ve never had this before in any other brew.

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If you taste diacetyl then I doubt it was an infection. 

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1 hour ago, Greeny1525229549 said:

What yeast you used mate. Had that with a few Belgian yeasts in my time. True top cropping yeasts.

That one was White Labs 001.

I actually don’t think it’s infection. I do think it’s slight Diacetyl. Not over the top just a little. However I also have never tasted Diacetyl so I’m not really sure. 

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Diacetyl at it's worst = obvious butterscotch & not like an under-attenuated beer that carries residual sweetness, & not like a beer that simply has too much crystal malt. Once you've tasted it, you never forget it. I rarely hear anyone mention it when using clean ale strains, except for the odd beer geek, or competition judge that over-analyse everything.

What was your actual FG vs expected FG?

Cheers,

Lusty.

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51 minutes ago, Beerlust said:

What was your actual FG vs expected FG?

Cheers,

Lusty.

Actual was 1.009 expected was 1.008.

so I’m going to give that spot on.

Im going to try again when I get back from work next Wednesday to see if it’s improved otherwise it’s out the back lawn 

Edited by The Captain1525230099

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