Diacetyl rest for ales

[Beerlust]

31 minutes ago, The Captain1525230099 said:

Actual was 1.009 expected was 1.008.

so I’m going to give that spot on.

Yeah FG appears good. The explosive ferment is a bit of a mystery, especially for this strain of yeast.

Purely speculating, but maybe this off taste is a byproduct of something relating to the abnormal ferment?

Cheers,

Lusty.

 

[The Captain!!]

3 hours ago, Beerlust said:

Purely speculating, but maybe this off taste is a byproduct of something relating to the abnormal ferment?

Yeah I really don’t know. But hey if it’s good when I get back, happy days

[Pezzza]

On 11/8/2018 at 6:38 PM, The Captain!! said:

Yeah I really don’t know. But hey if it’s good when I get back, happy days

What was the result Capitano?

[The Captain!!]

1 hour ago, Bearded Burbler said:

What was the result Capitano?

It was terrible and infected. My only infected beer. I stored it for sometime maybe 3-4 months, popped em open and all of em gushers. Out of control foam.

tasted and smelt even worse 

[Pezzza]

On 4/16/2019 at 10:32 PM, The Captain!! said:

It was terrible and infected. My only infected beer. I stored it for sometime maybe 3-4 months, popped em open and all of em gushers. Out of control foam.

tasted and smelt even worse 

Thanks Capitano.

Wow... that is sad to hear.  I have done many (most kit) and -- touch wood -- have only lost one where I unfortunately had enforced relatively poor brewing hygiene conditions, and then left it go for way too long in the Ferment Vat before bottling... even then it wasn't a gusher but it really did not taste so good to me so I poured it down the drain... 

But it certainly goes to show that wild yeast infection can change things radically... 

[Marty_G]

I do it  but it is more to do with keeping the same sort of routine for all my beers ...  I have just cold crashed an APA, E K Golding and Centennial hops, this afternoon after I arrived home but from a week away ... it had been at 18.5 for 9 days and the taste I did today when i checked the SG was pretty darn good so I crashed it... so from that I would say, no if you leave it long enough  ... I am of the school that the DA rest temp rise in lagers was to do with speeding up the process as lager fermentation is long and putting the temp  at the top of the ferment range just speeds up processes  ... 

[ChristinaS1]

On 11/5/2018 at 10:17 PM, The Captain!! said:

Its only in this beer which is my normal hoppy pale grist.

What is your process Captain? Don't you contain your dry hops in something and remove them before CC? Did you perhaps start the CC immediately after removal of the hops? If so, the diacetyl you are tasting might be due to hop creep. In that educational session on hops, on the Brewing Network, they talk about diacetyl being one of the hallmarks of hop creep (the other being a further drop in gravity). One of the work arounds is to let the beer rest for a couple of days at fermentation temps (or a couple of degrees higher) before starting the CC.

I can't say that I have ever noticed diacetyl in any of my brews,  not even back when I was still dry hopping commando style and leaving them in for the CC, but that might be more a function of my low dry hopping rates. But one thing I did notice is my bottles becoming more carbonated with the passage of time, and gushing towards the end of the batch.

After listening to the podcast, I decided to try both containing my dry hops in a bag and waiting to increase the temp by 2C until after I removed the dry hops, before starting the CC. I am hoping this will result in more stability of carbonation in the bottle.

Cheers,

Christina.

[The Captain!!]

Hey @ChristinaS1

Ive changed my process a little over time but at that time I was CC then adding contained hops. I never commando anymore due to the amount of hops I use. As one mentioned in other posts ended up as lawn food. 

Ive never tasted Diacetyl before well, to know exactly what that taste is anyway, so I don’t really know if it was that at all, had some green apple too. I’m going to call it a buttery fruit salad of funk. 

looking back I think it came from a starter I made that may have been left too long before pitching and got infected. 

 

[Otto Von Blotto]

I don't think hop creep is responsible for beer slowly overcarbonating over time. It sounds more like the yeast enzyme thing that breaks down previously unfermentable sugars. 

[Pezzza]

Forgive my ignorance - but what actually is 'Hop Creep' ?

[The Captain!!]

Basically, and please others don’t jump down my throat, I’m putting this basically.

there have been some studies that have had finished beer, then they have dry hopped those beers and the finished gravity has dropped. So being dryer. 

There are a number of reasons or factors that cause this but that’s the basics of it. 

Captain 

[ChristinaS1]

On 4/27/2019 at 2:39 AM, Bearded Burbler said:

Forgive my ignorance - but what actually is 'Hop Creep' ?

Here is a presentation about hop creep from Stone & Wood: http://brewcon.org.au/wp-content/uploads/2018/07/180628_1200-Final-BrewCon-Dry-Hop-Creep-21.6.18.pdf 

Cheers,

Christina.

Edited April 28, 2019 by ChristinaS1

[ChristinaS1]

I don't think hop creep is responsible for beer slowly overcarbonating over time. It sounds more like the yeast enzyme thing that breaks down previously unfermentable sugars. 

Thought I read that dry hops can lead to overcarbonation in the bottle. Hops contain alpha and beta amylase, limit dextrinase, and amyloglucosidase.  Most home brews don't pasteurize their beer, and some commercial breweries don't either. A lot of home brewers store their beer at room temperature, even after the bottle carbonation period. Enzymes can continue to work at ambient temperature, although some work better than others in this range. Some people also keep store bought beer at ambient temperature until shortly before use. 

What exactly is the yeast enzyme thing? An enzyme that breaks down previously unfermentable sugars sounds like limit dextrinase, but AFAIK yeast don't make limit dextrinase. What else could it be? Any enzymes from malt, and hops added during the boil, ought to be deactivated by the boil....

Cheers,

Christina.

Edited April 28, 2019 by ChristinaS1

[Pezzza]

19 hours ago, ChristinaS1 said:

Here is a presentation about hop creep from Stone & Wood: http://brewcon.org.au/wp-content/uploads/2018/07/180628_1200-Final-BrewCon-Dry-Hop-Creep-21.6.18.pdf 

Cheers,

Christina.

Thanks Captain.  Thanks Christina.  Makes much more sense now.   I would have thought adding hops that late is playing with fire at the best of times unless as a sterile hop tea... guess plenty brewers do it for the flavour and aroma... and I have been a plodding Kit Brewer for most of my time so not reaching those levels of excellence.

I think in my recent overcarbed wheat beer example it was nothing that exciting but more likely when I sampled the first bottle there were still unfermented fermentables - from a heavy malt load - in the bottles... the early bottles tasted ok... and behaved on the pour... but opening bottles much later... with the beer having been stored at ambient above 20degC...  had further secondary in-bottle ferment and ended up with overcarb...   I had a massive malt load in that brew which turned into a Weizenbok and was a bit too much really... 

 

[Otto Von Blotto]

I'm just wondering why it doesn't happen all the time. I've never experienced this hop creep overcarbonation in any of my beers and at least half of them are dry hopped. Maybe it happens in the fermenter before the cold crash, as I do leave it at 20ish for 2-3 days before cold crashing.

I also wonder if cold crashing denatures any enzymes that might be there in the same way heating the mash up to the high 70s does. If they work slowly, they might not have the time to really do anything before the temperature is dropped. Whatever the case, to me it seems like if the hops contain these things then it should happen most, if not all times, but that doesn't seem to be the case.

[ChristinaS1]

I'm just wondering why it doesn't happen all the time. I've never experienced this hop creep overcarbonation in any of my beers and at least half of them are dry hopped. Maybe it happens in the fermenter before the cold crash, as I do leave it at 20ish for 2-3 days before cold crashing.

AFAIK, cold temps do not denature the enzymes, just slows them down....pH plays a role. The enzymes are most active at pH 4.5, which marks the peak of the bell curve. There is still a good amount of activity at pH 4.0 though.

One thing I wonder about is how the duration of dry hopping plays into this. One of the charts in the Stone & Wood presentation shows the results of an experiment they did. They dry hopped the experimental arm of a batch of beer at around the 96 hour point (day 4) and the gravity continued to drop. Most of the drop happened by the 192 hour point (day 8), but it did not fully stabilize until the 240 hour point (day 10). Meanwhile the gravity of the control arm did not change after the 96 hour point. Reading between the lines it seems one should wait a minimum of 4 days after dry hopping before starting the cold crash, and up to 6 days....Up until now, my usual practice was to wait three days. 

Cheers,

Christina.

Edited April 29, 2019 by ChristinaS1

[The Captain!!]

From what I’ve been reading too is that it can be hop dependant. 

[Otto Von Blotto]

Well it's all largely irrelevant to me anyway. It's not gonna blow up or overcarb a keg even if it does happen

[The Captain!!]

1 minute ago, Otto Von Blotto said:

Well it's all largely irrelevant to me anyway. It's not gonna blow up or overcarb a keg even if it does happen

Exactly 

[Pezzza]

19 hours ago, ChristinaS1 said:

I'm just wondering why it doesn't happen all the time. I've never experienced this hop creep overcarbonation in any of my beers and at least half of them are dry hopped. Maybe it happens in the fermenter before the cold crash, as I do leave it at 20ish for 2-3 days before cold crashing.

AFAIK, cold temps do not denature the enzymes, just slows them down....pH plays a role. The enzymes are most active at pH 4.5, which marks the peak of the bell curve. There is still a good amount of activity at pH 4.0 though.

Agreed - I would suggest that the denaturing of enzymes caused by high temp would not take place at low temps re protein denaturation (most enzymes are proteins from memory... )

I think that Stone & Wood investigation did show it had probs re bottles and also quality control re client expectations.... 

But prolly not for you kegging brewers...  otherwise OVB - as you suggest - you could just give your keg slurping visitors their money back !?!

[Pezzza]

On 11/6/2018 at 7:09 PM, Beerlust said:

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.

Lusty my first AG Attempt is in the brew fridge at 18degC - and about half way through the planned ferment... copped this really interesting strong butterscotchy smell this arvo when I came back home... could that be the di-acetyl thing going on?  I plan for another 5 days and then to take it up to around 21-22 for a few days... my HB supplier/brewer reckons they do that as a routine... It really is just the key thing of ensuring you have gone through a full ferment and clean-up is it not - to avoid the di-acetyl festival? 

[Otto Von Blotto]

I'd bump it up tomorrow or the next day. No need to leave it another 5 days if it's already about half way through. 

I've never noticed diacetyl in any of my beers, ale or lager, tasting midway through fermentation and the obvious FG tests and finally in the glass. I don't really do anything special, just ferment temp then raise it a few degrees about ⅔ the way through, but I mainly do that to speed up the finishing off and cleanup. 

[Beerlust]

11 hours ago, Bearded Burbler said:

Lusty my first AG Attempt is in the brew fridge at 18degC - and about half way through the planned ferment... copped this really interesting strong butterscotchy smell this arvo when I came back home... could that be the di-acetyl thing going on?  I plan for another 5 days and then to take it up to around 21-22 for a few days... my HB supplier/brewer reckons they do that as a routine... It really is just the key thing of ensuring you have gone through a full ferment and clean-up is it not - to avoid the di-acetyl festival? 

Is it an ale or a lager yeast fermented brew? It sounds like an ale.

If it's an ale, I doubt you have anything to worry about. Ales are generally fermented in a higher temp zone than lagers where diacetyl is mopped up by the yeast almost automatically as part of it's cleanup of off flavours once FG has been reached. Being an ale brew it is already in a favourable temp zone to do this. Lager yeast fermented beers are in a cold temp zone & need to increase to that 18°C mark so that the yeast will mop up many of those off flavours including diacetyl.

I too like to let my ale brews free-rise toward the end of primary ferment, but it has nothing to do with diacetyl. It is to make sure the ale strain finishes off the ferment to expected FG levels, as I've encountered some strains that appear to get a little sluggish towards the end of ferment at lower temperatures.

If you do discover that horrible butterscotch flavour in the beer after primary ferment has completed, don't panic. Just make sure you secondary ferment (carbonate) the beer naturally using the yeast & make sure the bottles/kegs are stored at, or above 18°C. As part of carbonating the beer the yeast will mop up the diacetyl with it.  (A handy little tip there from PB2 a few years back) 

Cheers & best of luck with the brew,

Lusty.

[Otto Von Blotto]

Lager yeast will mop up diacetyl regardless of raising the temperature. It just happens faster if the temperature is raised. It's a misconception that it needs the temp raise to mop it up. 

The slow ramp down to lagering temps also facilitates cleaning up the beer, as the yeast will still work at 3-4 degrees. I've certainly noticed an improvement in my lagers since I started doing this instead of dropping them straight to zero.

[Beerlust]

4 minutes ago, Otto Von Blotto said:

Lager yeast will mop up diacetyl regardless of raising the temperature. It just happens faster if the temperature is raised. It's a misconception that it needs the temp raise to mop it up. 

The slow ramp down to lagering temps also facilitates cleaning up the beer, as the yeast will still work at 3-4 degrees. I've certainly noticed an improvement in my lagers since I started doing this instead of dropping them straight to zero.

That lager I brewed where I missed the diacetyl rest point & kegged it displaying that horrible butterscotch flavour did not improve one iota over a month to 6 weeks in the keg.

My kegs sit between 2-5°C. It's a mistake I won't be making again.

I dare you to test that theory. 

Cheers,

Lusty.