Struggling with Pentainedione - Home Brew Forums
Register Now For Free!

Home Brew Forums > Home Brewing Beer > Fermentation & Yeast > Struggling with Pentainedione

Reply
 
Thread Tools
Old 03-06-2013, 02:40 PM   #1
-MG-
Recipes 
 
Dec 2011
Cedar Rapids, IA
Posts: 333
Liked 1 Times on 1 Posts



For my understanding Pentainedione is a bi-product of fermentation just like diacetyl, and are somewhat similar.

Any light beer or ale I make seems to suffer from this. It's not a bad buttery sweetness (may be desirable in certain styles). I noticed from my very first extract batch from 3 years ago, to now my all grain setup which is a Kal clone. It wasn't until recently that I really started to notice a similar taste in a lot of my beers. It is characterized by a caramel/honey aroma and initial taste, to a sweet buttery after taste, but its not an in your face buttery like diacetyl is. My friends love the beer and they don't taste bad, but if I attempt to make any light or medium body beer its dominated by this flavor and no matter the grain bill or hops, they taste the same.

I spent some time talking with a local beer club member who studies these things and we are kind of stumped.

Here are some things I do:

I cool the wort to pitching temperatures within 15-20 minutes.
I aerate the wort with pure oxygen and do the purge and shake method which according to a dissolved oxygen meter, gets the oxygen levels to 10ppm which should be plenty for the yeasties.
I just started pitching more aggressive rates, using .75 million cells/ml/degree of plato. Which is more than most of do, thinking my pitching rates were an issue.
I ferment in plastic carboys that always get a good oxy-clean soak for almost 24 hours after use, never used a brush inside them.

I tasted a blonde ale that had a few points of gravity to go and it tasted great, no signs of the issue, a few days later once I hit my FG, I took a sample and sure enough it was dominated by a honey/caramel flavor with that sweet aftertaste.

At this point I can pin point it to fermentation (as evidence by the above statement). Which makes since, since this is a bi-product of fermentation, but, why aren't the yeasties cleaning up after themselves? I usually ferment my ales in the mid 60s sometimes low 60s. I've never struggled with a stuck fermentation or not hitting my FG.

At this point I ordered some Biomat Dar from midwest supplies, which is suppose to suppress the creation of diacetyl and will try that, but its unbelievable to me after going through all of my processes that I am struggling with this.

I also am going to try krausening the blonde ale that I am talking about shortly here. While I'm not using it for carbing, I plan to make a starter with US-05, decant the liquid and pitch the active yeast to see if maybe they can clean up the issue.

I'm hoping that fixes it, but it just makes me wonder why I have to go through all of that to get a clean tasting beer.

Additional note, I mostly struggle with this issue with my ale's and usually use US-05.

Thoughts?

 
Reply With Quote
Old 03-06-2013, 03:18 PM   #2
gotsumbeers
 
gotsumbeers's Avatar
Recipes 
 
Apr 2012
North Beach, MD
Posts: 135
Liked 5 Times on 5 Posts


I was just getting ready to post on the forum about something similar. I have just made three batches of beer that all used 2nd generation washed S-05. All of the batches were primaried in the upper 60's for a couple of weeks or more, then crash cooled and kegged.

Each beer had a different grain and hop bill. Each beer has a noticable honey flavor. Blind tasters have commented that I should scale back honey or honey malt when none was used. It is not disagreeable and most everyone liked the beers, but is is not intended.

I suspect the S-05 is the culprit. I have a split batch fermenting one with same S-05 and the other with WLP550. Will post results.

Anyone have other ideas?
__________________
"Tastes like mom's"

 
Reply With Quote
Old 03-06-2013, 03:21 PM   #3
krackin
Recipes 
 
Nov 2012
, NH
Posts: 1,098
Liked 258 Times on 184 Posts


I thought you were wrestling with a Greek Goddess. Never mind.

 
Reply With Quote
Old 03-06-2013, 06:20 PM   #4
-MG-
Recipes 
 
Dec 2011
Cedar Rapids, IA
Posts: 333
Liked 1 Times on 1 Posts


Quote:
Originally Posted by gotsumbeers View Post

I suspect the S-05 is the culprit. I have a split batch fermenting one with same S-05 and the other with WLP550. Will post results.

Anyone have other ideas?
I haven't really thought much about this, only because so many people use US-05 and don't have an issue. But its possible that something about the water chemistry or what have you and the us-05 isn't blending right.

I will be very curious on your results, whats the time line for your fermentation?

 
Reply With Quote
Old 03-06-2013, 07:06 PM   #5
gotsumbeers
 
gotsumbeers's Avatar
Recipes 
 
Apr 2012
North Beach, MD
Posts: 135
Liked 5 Times on 5 Posts


It is almost a week in to primary. I plan on having it kegged by the end of the month. I have soft water I run through a charcoal filter and add a little gypsum to my hoppy ales.

We'll see.
__________________
"Tastes like mom's"

 
Reply With Quote
Old 03-06-2013, 07:14 PM   #6
gotsumbeers
 
gotsumbeers's Avatar
Recipes 
 
Apr 2012
North Beach, MD
Posts: 135
Liked 5 Times on 5 Posts


Also, I've used S-05 straight from the packet and it is great. Clean and crisp no off flavors. All these beers used the washed yeast, which is still clean and crisp but with a touch of honey.
__________________
"Tastes like mom's"

 
Reply With Quote
Old 03-06-2013, 07:17 PM   #7
maida7
Recipes 
 
Nov 2009
Asheville, NC
Posts: 2,827
Liked 48 Times on 41 Posts


Pitch cool but try fermenting a little warmer like upper 60's Also, try warming the fermenter into the low to mid 70's as the actions slows down. Warming towards the end will keep the yeast active so they can clean things up.

 
Reply With Quote
Old 03-06-2013, 08:36 PM   #8
-MG-
Recipes 
 
Dec 2011
Cedar Rapids, IA
Posts: 333
Liked 1 Times on 1 Posts


Quote:
Originally Posted by maida7 View Post
Pitch cool but try fermenting a little warmer like upper 60's Also, try warming the fermenter into the low to mid 70's as the actions slows down. Warming towards the end will keep the yeast active so they can clean things up.
I've looked down this route as well, and even had a few beer ferment in the mid 70s and still get this taste.

It's not diacetyl because the flavor is characterized more by the honey/caramel flavor than the sweet after taste. I'll probably brew another blonde ale and try a different yeast strain like a kolsch yeast or something else.

It's not a bad taste either so I find it hard to believe its oxidation or some other common off flavor. I need to listen to the brew strong episode where they talk about this.

I don't want to try WLP001 since I understand that its basically the same strain as US-05. To be honest there are only few things in common from my first extract days to now they are:

Water
Yeast
Plastic Carboy

I soak all my carboy's overnight with warm pbw and never use a brush inside so I find it hard to think it the carboy. I've never heard of anyone saying the water would cause this and I have excellent brewing water.

At the same time though, I brewed an oktoberfest and used WLP820 and it had some bitter flavor that was somewhat in line with this as well, but different. I took the kegs out of the lager chamber and they have been at room temperature the last month. I'll give it a taste to see what that looks like. I have a hard time comparing that though since its a lager yeast.

 
Reply With Quote
Old 03-06-2013, 08:44 PM   #9
maida7
Recipes 
 
Nov 2009
Asheville, NC
Posts: 2,827
Liked 48 Times on 41 Posts


I assume you use some sort of sanitizer after you rinse out the PBW...

perhaps it's just your taste buds. Our minds can play tricks on us when it comes to tasting things. I'd have some experienced beer judges taste it. Maybe enter a few comps.

If Pentainedione is a real problem in your beer, I suspect it's related to how you manage the ferment. Reading your OP the first thing I'd change is the temp.

 
Reply With Quote
Old 03-06-2013, 10:08 PM   #10
dawgmatic
 
dawgmatic's Avatar
Recipes 
 
Nov 2011
Milwaukee, WI
Posts: 517
Liked 35 Times on 34 Posts


http://www.homebrewersassociation.or...-beer-gone-bad

Homebrewers association attributes pentanedione as one of the unfortunate results of oxidation.
__________________

Quote:
Originally Posted by Revvy View Post
People's brains are interesting....and tasty too.

(See what I did tthere? ;))

 
Reply With Quote
Reply
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Struggling with a DIY stirplate Havacore Chillers & Stir Plates 9 01-15-2013 04:41 AM
Struggling with BS2 on new system enricocoron Brewing Software 0 11-08-2012 09:08 PM
struggling with all grain 70Cuda383 All Grain & Partial Mash Brewing 8 01-08-2012 03:33 AM
Struggling jldc All Grain & Partial Mash Brewing 2 06-19-2011 12:21 AM
Struggling with calculations GLWIII Beginners Beer Brewing Forum 3 06-08-2008 03:25 PM


Forum Jump