Unwanted Candy Flavours In My Lagers

[huisbrouwen]

I've just finished four batches of various lagers.. a marzen, munich, pilzner and dark.. all give a sweetish rock candy finish on the back palate... all have been brewed meticulously from extracts, bitter hopped carefully in a half hour rolling boil with partial liquid extract, adding aroma hops and remaining dry and liquid extracts at the end of the boil, ensuring all are thoroughly dissolved, and added while the boil is rolling. I have only sparingly used corn adjuncts in a few of the brews, and all were feremented at around 12C with a saflager yeast over 14 days, ensuring all have fermented right out. 750ml bottles were primed with white cane suger and have matured for between 8-4 weeks respectively.

What is giving this, not unpleasant, but unwanted flavour in what should be hoppy dry beers? it's only present on the back palate and dominates the hop flavour... there are no unpleasant esthers indicating hygene is not a problem (I'm an experienced brewer using diluted bleach, rinsed) , and body and head retention are excellent.

Any help gratefully recieved.
G

 

[tangent]

extract = unfermentable dextrins
nice for stout, crap for lagers

you sound like you have the smarts to make porridge and wash the sugars from it, come over to the dark side

 

[redgums500]

I've just finished four batches of various lagers.. a marzen, munich, pilzner and dark.. all give a sweetish rock candy finish on the back palate... all have been brewed meticulously from extracts, bitter hopped carefully in a half hour rolling boil with partial liquid extract, adding aroma hops and remaining dry and liquid extracts at the end of the boil, ensuring all are thoroughly dissolved, and added while the boil is rolling. I have only sparingly used corn adjuncts in a few of the brews, and all were feremented at around 12C with a saflager yeast over 14 days, ensuring all have fermented right out. 750ml bottles were primed with white cane suger and have matured for between 8-4 weeks respectively.

What is giving this, not unpleasant, but unwanted flavour in what should be hoppy dry beers? it's only present on the back palate and dominates the hop flavour... there are no unpleasant esthers indicating hygene is not a problem (I'm an experienced brewer using diluted bleach, rinsed) , and body and head retention are excellent.

Any help gratefully recieved.
G

G

Maybe have a look a the temp which you are storing the bottles. Perhaps not all the priming sugar has fermented out. Although you did mention that the head retention was good. Maybe place them in a warmer spot for a few days before lagering them again. I haven't used bottles for years so probably I'm out of my depth here Tangents right... the best lagers come from AG. But trying to fing the time is the biggest hurdle.

cheers

Redgums

 

[Enerjex]

the brews extract/partials i've made with liquid and dry malt extract have all had a strange sweetness on the back of the palate. it's most likely the malt extract doing it. it's done it to me with dried, coopers liquid and black rock liquid.

 

[Mr Bond]

Yep Tangents on the money. Extract.

It will never attenuate down low enough ,no matter what yeast or how much aearation.The manufacturing process sees it mashed at higher temps than an AG lager maker would use.
Never had an extract lager pilsener yet that was crisp and clean
Learn to like the character or start mashing basically

 

[jayse]

You don't really have to mash to make a crisp dry lager you can always just use some dextrose for some of the fermentables to help with the lower attenuation expected from some extracts.


For a Australian lager Full mash beers have been beaten by beers made with a can of bilo draught and dextrose in comps before in fact the bilo can has placed first. Not very likely that would ever happen with a munich style beer though. <_<
Just pointing out that telling extract brewers the only way they can help their beer is to go full mash is not always true. There are other thing to look into aswell.
Personally I think a bit of grain should go into every beer if your after making the best beer possible but thats another story.

One thing to note,
There are ways to find out the expected attenuation of extracts such as forced fermentation at high temps of a small amount of the batch with lots of yeast etc.

 

[tangent]

actually, uncle Kenny made a drinkable extract lager.
I'll take a bag of Wey Pils anyday though.

 

[Wasabi]

Did you raise the temp at the end of the ferment? You didn't mention it in your description.

The sweet flavour could be diacetyl and if you didn't give it a diacetyl rest (ie raise the temp to get the yeast to get rid of the diacetyl) after you hit your FG there could still be quite a bit floating around. I'd describe it better as butterscotch, but rock candy might be appropriate.

 

[wildschwein]

I agree with Wasabi. When I read this post the 1st thing that came to mind was diacetyl. It leaves a sweet butterscotch-like flavour in beers. Could be the problem,as Wasabi says, just raise the temp at the "end" of fermentation (when FG is achieved) to about 18C for 2-3 days for the yeast to knock it off.

 

[Ross]

I agree with Wasabi. When I read this post the 1st thing that came to mind was diacetyl. It leaves a sweet butterscotch-like flavour in beers. Could be the problem,as Wasabi says, just raise the temp at the "end" of fermentation (when FG is achieved) to about 18C for 2-3 days for the yeast to knock it off.

Not quite - raise the temp once the gravity drops below 1020 (for a typical brew). If you wait until Fg is achieved, the likelyhood is the yeast won't have enough grunt to clean it up.

Cheers Ross

 

[huisbrouwen]

Not quite - raise the temp once the gravity drops below 1020 (for a typical brew). If you wait until Fg is achieved, the likelyhood is the yeast won't have enough grunt to clean it up.

Cheers Ross

Interesting.. no, i didn't raise the temp at the end... but I will try it with the next one.. also the bottles have been stored at pretty low temperatures (it is a lager after all). And come to think of it one of the stouts I've done from extract has also a very small sweetist hint.. it's not quite butterscotch, more like a boiled lolly,

thanks all for your sage advice.
G

 

[SJW]

I tend to agree with Tangent. If u are using extract you have no idea or control over what mash condition were. So I would have to say if everthing else went to plan, ie. fermentation temps, priming temps ect... the only thing left would be the extract.
Time to come over to the dark side.

Steve

 

[matti]

I've managed to get really dry lagers with extract and partial mashes.
I make sure the liquid malts is relative new and a good brand. (Black rock)
I make sure i use very small amount of crystal grains if any.
A diacetyl rest and bulk prime with Dextrose.
helps but not nessecary.

 

[floppinab]

remaining dry and liquid extracts at the end of the boil, ensuring all are thoroughly dissolved, and added while the boil is rolling.

Have been doing a few extract brews lately and have not been doing this because I've been worried about a high amount of sticky liquid malt hitting the bottom of a very hot vessel and potentially doing something weird to those concentrated sugars before they get a chance to dissolve properly into your wort. Intuitively it fits your rock candyish flavour description). I tend to throw my LME in once the boiled wort has cooled just a little from the boil.

Not discounting anything already said and I may be way off the mark but maybe another theory to throw in.

 

[Wasabi]

Not quite - raise the temp once the gravity drops below 1020 (for a typical brew). If you wait until Fg is achieved, the likelyhood is the yeast won't have enough grunt to clean it up.

Cheers Ross

Hmmm...not sure I fully agree with you there Ross, but logistically it's probably easiest to start the rest at 1020, especially if you are using artificial chilling. Just switch it off and let the yeast heat up the beer for the final few days.

 

[Tseay]

Classically fruity ester flavours are the result of under-pitching, yeast style and fermentation temps.

http://www.byo.com/referenceguide/troubleshooting/

If you used the S-23 variant then that may be part of the issue as fermentis reports fruity ester flavours with some lagers. Is it possible that you fermented at below 12 C ?

have look at the comments on the fermentis site :

ttp://www.fermentis.com/FO/EN/06-Ales/30-10_product_hb.asp

 

[Ross]

Hmmm...not sure I fully agree with you there Ross, but logistically it's probably easiest to start the rest at 1020, especially if you are using artificial chilling. Just switch it off and let the yeast heat up the beer for the final few days.

Just quoting Dr Chris White from Whitelabs

[dgonzalez] i think some of the guests might find this topic interesting. can you describe, in simple terms, how a diacetyl rest works? it's benefits? and downfalls of not doing one?
[cwhite] yeast make a compoud called acetolactate.
[ale] Excellent question, DG.
[cwhite] This goes outside the cell, where it is later oxidized to diacetyl.
[GSchmidt] ?
[cwhite] If yeast are still there and are metobolicly active, they will reabsorb it. If the yeast are removed, or are done, they might not reabsorb the diacetyl.
[cwhite] For lagers, you need to raise the temperature to ~65 for 1 week, starting when the beer is about 1.020. If you go much lower then that, the yeast will not be working strong enough to take up the diacetyl.
[cwhite] For ales, you only need to go 24-48 hours post terminal gravity, since you are already at ~65 F temperatures. This is why lagers will taste buttery later, you can't taste the precurser, and once you remove the yeast, it will turn into diactyl later.

Cheers Ross

 

[Wasabi]

Just quoting Dr Chris White from Whitelabs



Cheers Ross

Interesting..... At this point in fermentation the yeast are still actively producing acetohydroxy acids and being decarboxylated to diacetyl, so I would have thought that even though they scavenge the Diacetyl faster than they make acetohydroxy, they are still taking two steps forward and one step back. Kunze reckons that diacetyl removal happens 10 times faster than production once the oxygen has been consumed and fermentation is well on it's way, so most gets removed before the diacetyk rest anyway.

Plus if the yeast is still active enough to bottle condition, I'd have thought it was still viable enough to consume diacetyl, especially if you are using a hardy lager yeast. I wonder if huisbrouin is bottle conditioning his lager, and therefore producing even more diacetyl. Especially so if he is just gravity filling his bottles and introducing more oxygen which results in more diacetyl...perahos beyond the ability of the yeast to remove it in bottle conditioning.

I think there are also a lot of other factors particular to the yeast strain. Yeast is better at diacetyl reduction when it's still in suspension, so perhaps a low flocculant yeast would be better at it?

In a Biochemist Vs Microbiologist war I reckon only the text book publishers would win!


Might see if my supervisor will let me do a little experiment. Grab some beer at 1020 and diacetyl rest it and again at 1010 and diacetyl rest that. Then run both samples through the GC and see what the diacetyl levels are like.

B)

 

[huisbrouwen]

Averything is pointing towards diacetyl.. this is how John palmer describes it on his website...

"Diacetyl
Diacetyl is most often described as a butter or butterscotch flavor. Smell an unpopped bag of butter flavor microwave popcorn for a good example. It is desired to a degree in many ales, but in some styles (mainly lagers) and circumstances it is unwanted and may even take on rancid overtones. Diacetyl can be the result of the normal fermentation process or the result of a bacterial infection. Diacetyl is produced early in the fermentation cycle by the yeast and is gradually reassimilated towards the end of the fermentation. A brew that experiences a long lag time due to weak yeast or insufficient aeration will produce a lot of diacetyl before the main fermentation begins. In this case there is often more diacetyl than the yeast can consume at the end of fermentation and it can dominate the flavor of the beer."

Heaters now on in the final stages of my dark lager.. lets see if it works.

thanks again guru's

 

[Weizguy]

Just in case you have a barley sugar flavour, rather than a butterscotch one, I find that all my DME beers have it when young.
It may need a little time to go away, and that's probably dependent on warmer conditioning temp.

I have made a number of delicious wheat beers with DME and actually quite enjoy the complexity of the barley sugar flavour when young, especially in an otherwise dry, well-attenuated beer.

If your "candy" flavour is not going away, just try and leave a few bottles in a warmer part of the house for 2-4 weeks. Then chill and sample.

My 2 cents
Beerz
Seth