Butterscotch flavour from US05

[Damien13]

I went to a tainted beer tasting, and the beer dosed with Diacetyl tasted butterscotchy/werthery to me. Some people can't even detect it in bucket-loads. So I think the perception of it varies. weird. Don't actually taste the popcorny buttery thing people talk about. I taste sickly sweet caramel.
I HAVE had a few blows to the head in my time, which explains a lot

 

[Nick JD]

I wonder if the artificial butter flavour they added was sweetened, because diacetyl itself isn't sweet.

 

[manticle]

Just to clarify, diacetyl tastes like the smell of buttered popcorn, not like a Werther's Original.

Actually diacetyl, like many other compounds in beer will be perceived differently depending on the concentration, the beer it's in and the perception of the taster, including their threshold.

You might usually taste it as buttered popcorn but that isn't the only descriptor not is it the way it will always be perceived, even by you necessarily.

For example I have smelt and tasted acetaldehyde as the typically described green apple but more often than not, I get pumpkin skin and/or paint emulsion. Same chemical, different perception. This is both from doctored and undoctored beer samples.

If you ever do some kind of a fault/taint tasting session, taste the tainted beer at the beginning then leave the sample, covered till the end. re-taste. You may be surprised at how different qualities will be perceivable even after just an hour or so (suggesting temperature will also play a part as well as volatility).

 

[brad81]

This link: http://www.howtobrew.com/section1/chapter8-2-3.html might help to clarify why you might be getting those flavours. Are you finishing the ferment quickly based on the hydrometer readings alone?

I bought the hardcopy and read it a few times before I had any of my brewing gear in order. I heartily recommend it.

I've been leaving my ales fermenting (using US05 almost exclusively) in the primary fermenter for about 3-4weeks at a temp of about 20-22. I have yet to encounter any butterscotch/butter/diacetyl notes in any of them.

Like manticle pointed out, you'll notice some more fruit notes, but when using hops like amarillo and cascade, I believe it adds to the taste more than it takes away/overpowers.

 

[Nick JD]

How many people here can taste butterscotch in margarine? I sure can't. Tastes a lot like butter though.

What's the primary artificial flavouring in margarine....

 

[manticle]

I find marge and butter completely different. Similarity is colour (sort of) but flavour is not in the ballpark for me.

Flavour descriptors of compounds are often by psychological association too (although things like diacetyl are sometimes added to commercially avaiilable buttered popcorn, acetaldehyde is present in some acrylic paint emulsions, etc, etc).

 

[tiprya]

The best example of diacetyl for me is chardonnay, some just reek of it.

Smells buttery to me, not butterscotchy.

 

[Nick JD]

I used to do Boh Pils with a lot of melanoidin, as I got sick of pissing about with decoctions. I'm talking ~8% melanoidin.

In secondary, I'd always be resting the hell out of them, because they were very sweet and butterscotchy - 18C for days and days, and the "butterscotch" would invariably never fade. I gave up doing the rest because it made little difference. I even started thinking I might have a diacetyl infection, yet my APAs rarely tasted of butterscotch.

Then I made a Boh Pils without any melanoidin. Eureka ... tiny bit of diacetyl, eliminated by a rest. No butterscotch.

Started looking into what diacetyl actually tastes like. And what decoction-based melanoidins taste like.

Suddently occured to me also that I never ever got "butterscotch" in any beer that contained zero spec malts.

As always YMMV.

 

[Bizier]

I often associate diacetyl with a form of sweetness. It gives a similar rounding-out sensation to back-sweetening and significantly alters my perception of dryness. Depending on concentration I get different things, but at the highest concentration (riddled with vdk) I get butter menthols minus the menthol.

 

[Goose]

actually i struggle to asscociate diacetyl with popcorn, butterscotch or butter which are desirable tastes.... diacetly is its own vile animal in my mind and I can detect it at a thousand paces. I have always hated honey as a taste on its own and if you do you will be able to detect diacetyl's next of kin 2-3 pentanedione easily, and diacetly is very close....

 

[Goose]

Artificial Butter Flavouring Linked To Alzheimer's Disease Risk

The Huffington Post UK

Posted: 03/08/2012 12:01 Updated: 03/08/2012 12:38 | By Kyrsty Hazell







A buttery food flavouring ingredient found in microwave popcorn could intensify the damaging effects of abnormal brain proteins linked to Alzheimer’s, a recent study has suggested.




Diacetyl (DA), an artificial food flavouring that gives popcorn and margarine its distinctive butter taste, encourages beta-amyloid proteins in the brain to ‘clump’ together, according to findings published in the Chemical Research in Toxicology journal.
This damaging ‘clumping’ process is a hallmark for Alzheimer’s disease.

Artificial butter flavouring linked to Alzheimer's

Researchers from the American Chemical Society also warned that DA could easily penetrate the so-called ‘blood-brain barrier’, which prevents harmful substances from entering the brain.
Furthermore, the artificial flavouring also stopped a protective protein called Glyoxalase I reaching the brain – a key protein that safeguards nerve cells.
"In light of the chronic exposure of industry workers to DA, this study raises the troubling possibility of long-term neurological toxicity mediated by DA," researchers said in a statement, reports Science Daily.
However, researchers added that the study focused on factory workers who worked at microwave popcorn and food-flavouring factories, and were therefore more exposed to the chemical.What is Diacetyl?Diacetyl is a natural byproduct of fermentation.The DA chemical also forms naturally in fermented beverages such as beer, and gives some chardonnay wines a buttery taste. Diacetyl, at low level, gives beer or wine a slippery feel. At higher levels one can taste a butterscotch flavour.

 

[brentice]

I use Danstar nottingham ale yeast and have never had an issue with diacetyl. Only used US-05 a couple of times and it doesnt strike me as an amazing yeast. Then again its different strokes for different folkes :beerbang: :beerbang: :beerbang:

 

[manticle]

Battled a sweet/honey/butter aroma in beers using 05 for years before listening to a podcast interview with Dr Charlie Bamforth. Now I pitch a little extra yeast, and wait two weeks minimum before chilling.

Look up Vicinal diketones (VDKs). The two major VDKs of concern to the brewer are diacetyl (2,3-butanedione) and 2,3-pentanedione. Google Vicinal diketones and Charlie Bamforth.

Also had a similar result caused by an infection when open fermenting. Gave the inside of the fermenting fridge a good seeing to with bleach and vinegar solution, problem solved.

Screwy

I was going to start a new thread but found this post.

I have a vienna lager that has a massive amount of diacetyl pre-lagering despite pitching an active 6L starter (albeit from 1 smack pack) at 4 degrees and allowing to rise to 7, then d-resting for a few days as high as 20. Should probably mention it uses a wyeast munich lager yeast, not US05.

A couple of things I have probably done wrong - d -rest should probably have started earlier - 1/2 -3/4 the way through rather than so close to FG and maybe bite the bullet and use 2 packs or push for an 8L starter (1045 starting gravity, 22 Litres).

Anyway I'm trying to work out ways to reduce the levels that are there and came across the interview I think Screwy is referring to.

http://beersmith.com/blog/2012/01/29/diaceytl-in-beer-with-charlie-bamforth-beersmith-podcast-31/


Worth a listen. I have another lager which is a bit of a leftovers so I decided to use the yeast cake from the vienna, some of which I put into a 1030ish starter, diluted from the same wort. A portion of that active yeast has gone into the vienna which is at 15 degrees and I will slowly drop the temp to 1 degree and lager for as long as I can.

Even if my beer still tastes like butter, the interview is a good one.

 

[manticle]

An update on the above for anyone who cares. I top cropped some yeast from the next lager I got going (yeast cake from the first built into a starter) back into the first. I know lager yeasts aren't top cropping yeasts so no-one please try and tell me that.

Anyway the diacetyl is now reduced below my perception threshold so that works well. However the distant cousin - the 2-3 pentadione whatever thing that tastes like honey is very distinct. I don't hate it so i will likely just bottle it and drink it happily at home.

What is worth noticing is that the other batch was given a proper diacetyl rest. I raised the temp by about a degree a day once it was about 2/3 the way through, left it at 18 for 2 days and am now slowly dropping it back till it hits zero (again 1 - 2 degrees a day).

Not a hint of diacetyl or honey and exactly how I will do it again for all future lagers.

 

[Nick JD]

I recently made a diacetyl bomb German Pils by pitching big and warm.

No amount of resting got rid of it.

When I pitch small and warm, it's okay. And pitching big and cold is okay too.

Not sure what's going on, but I think a big warm pitch the yeast spend the first day just churning butter.

 

[KingKong]

I've finally worked out US-05 for my fermenting system. I used to get heaps of Butterscotch / honey . By doing everything I can to look after the yeast health and stress I have this far eliminated the butterscotch and honey taste for my perceptible levels.

Things I changed to get there

1. Re-Hydrating as per manufacturers instructions and temps instead of pitching dry. - This helped BIG TIME, but some honey still present until a couple of months conditioning.

2. Using a D-Rest - Upping my temp from 18 to 21 half way through fermentation, through to complete fermentation, then back down to 18 for a week of conditioning. Pretty much solved the problem.

3. Using pitching levels at the higher end of recommended levels.

Don't have any problems with butterscotch or honey any more.

Not sure if it will work for everyone , but for me getting US-05 right has been the most satisfying part of my brewing to date. I'm now confident to move onto other ale yeast that might not be as forgiving.

...Not advice just my experience.