Infected Ag (40ltrs And 6hrs) Down The Toilet

[wedge]

So on Sunday, nice and excited i did two batches of lager AG.

Sparged and boiled one, got temp down to 30oC then waited till next day to pitch yeast, at 23oC.

Sparged the other, and waited to today (2 days later) to boil as i ran out of time!

Both beers have a 'corn' flavour, only one has been boiled, what's the deal?

Any help or comments will be appreciated. Maybe it's not really infected

 

[johnno]

geez wedge,
I hope it goes ok. Sorry I'm not experienced enough to offer any advice on this. I will pray to the beer gods though.
It would be a bummer to lose all that beer.

all the best with it.

 

[JasonY]

hmm by corn flavour so you mean really pronounced like you would expect when your eating a cob of corn!

Can't say I have had anything like this, whenever I taste mine after boiling I find them sweet but with a very bitter bite from the hops which mellows dramatically with fermentation.

If you post the recipe some people may have something to add, maybee with the grain and hop bill you get a funny taste.

If it were me I would pitch some yeast in the boiled one and see how it goes, store the second unboiled one or boil and pitch there too. Taste it after primary and see if it is any better .... :unsure:

 

[wedge]

its funny because when he gave me some of my grain there was a piece of corn in it? Coincidence, most probably.


I wonder what oxidation taste like, i really doubt that after a 110min boil there would be any infection!

 

[big d]

well im up to ag #4 and other than two in the fermenter the other two are cc-ing.
hope they end up all right as other wise i will be joining you wedge trying to work out where i went wrong.
not much help on the corn taste .
maybe you can post your grain bill and what yeast you used.may help track down a culprit

cheers
big d

 

[Batz]

Could it be husky/grainy flavours?

these can be more evident in AG brews , due to poor grain crushing or sparging pracitices.
Perhaps grain husks were shredded during crushing

CC for a month or two will often cause these harsh compounds to settle out with the yeast

from Palmers book

 

[wedge]

this could be very much it Batz, a very strong sweet (of course) grain taste!

When i bought the grains from the shop (a shop that should know better) i thought the crush was pretty average.

The only problem is that i dont know a lot about crushing grains!

I kept the munich lager, but i've chucked the pilsner :angry:

We can only hop!


Recipes where basically 5kg each recipe
700g and 300g munich each
100g rye and 100g wheat each


I dont think is was my sparge, i did it the same way i always do it. But i can only be prepared to adapt.

 

[Batz]

I would try the CC treatment , if only a few bottles to prove a point

I did a partial Corona a while back , tasted **** out of the keg , I was sure it was infected so tipped it out , I usually do a couple a stubbies of each brew to try after a few months.

Tried one of these last night....you guessed it , was exellent

 

[Jovial_Monk]

Corn flavor does not sound like an infection. It is a taste some lagers have after fermentation and (I think, books are at home) is due to DMS. Just lager the beer a few weeks and you will be fine.

Did you boil covered? HB lore says that will trap the DMS/corn taste though I am not convinced.

Wish I could be more help but I brew 99% ales, however, I will look the corn taste tonight at home.

To repeat, corn does NOT sound like an infection


Jovial Monk

 

[wedge]

i had my doubts about the infection as one batch had been boiled and the other hadn't though both had this sweet corn/grain taste!

Thanks for the ideas guys

 

[Justin]

Just a snippit I found a minute ago. Hope it helps.

DMS
DMS, or dimethyl-sulfide produces the aroma and taste of cooked vegetables, notably corn, celery, cabbage or parsnips. In extreme cases, it may even be reminiscent of shellfish or water in which shrimp has been boiled. DMS is normally produced by the heat-induced conversion of S-methyl-methionine, but most of this evaporates during an open, rolling boil. A closed boil or slow cooling of the wort may therefore lead to abnormally high levels. Some DMS is also scrubbed out during a vigorous fermentation, which is why lagers and cold-conditioned ales may have slightly higher levels than warm-fermented ales. Wild yeast or Zymomonas bacteria may produce high enough levels of DMS to make the beer undrinkable. Low levels of DMS are appropriate in most lagers, particularly American light lagers and pre-prohibition pilsners, but are not desirable in any ale style.

Cheers, JD

 

[big d]

total stab in the dark here but could the rye have something to do with the corn taste.
probably wrong but you live and learn.

cheers
big d

 

[Jovial_Monk]

Slow wort cooling sounds like the suspect.

Do you have a chiller, wedge?

taste threshhold of DMS is 30 parts per billion, sounds low to me. some yeast strains form it as a by product, some bacteria produce copious DMS, but I bet it is the slow wort cooling

Jovial Monk

 

[wedge]

ok, one batched dropped to 30oC in about 20mins with my copper coil.
Then over 12 hours dropped to 20oC.

The other batch was thrown straight into the fridge without cooling after the sparge.

The rye was only in one batch, yet this taste in both.

It was a ridiculous 44oC when i brewed, my boiler has a fully opened top and only one batch had yeast pitched.

I really stumped, i think it could have been the crush!

 

[big d]

i would discount the crush other wise most ag info would be saying in all manuals etc to avoid a particular size crush.else you end up with corn tasting beer.
just out of curiosity wedge you may have a bad mix of grain.
ive noticed while measuring out my jw pale malt there is the occasional odd looking grain that is not barley.round shaped so is some other type of grain/bean.
might be worthy of the x-files.

cheers
big d

the mystery deepens

 

[Barry]

Good Day
As been said by others the DMS is at much higher levels if the cooling is slow ie more than 30 mins. The commercial breweries cool the wort in a matter of seconds. Pilsner malt tends to have higher levels of DMS than pale malt.
All the best, Barry

 

[Andrew Clark]

Hi Wedge,
I think the problem you are having with the corn aroma stems from not boiling your second batch ( if I read your post right). It is absolutely essential to boil the wort of an all grain brew, this stops enzymes from continueing to work, it allows the hot break material to seperate form the wort, hot break can lead to corn flavours and aromas as well. Plus if you didn't boil the second batch it would not have contibuted any bittering to the brew intself, which would have further enhanced the corn flavour /aroma..
Regards
Andrew

 

[Jovial_Monk]

Bit puzzling, I used to cool to 30C, pitch and let it cool overnight to 20C, no cooked corn flavor

But I bet it is DMS, slow wort cooling or you have an infection after all, the one that produces bulk DMS.

A crush or mix of grains, even 500g of flaked maize do not produce a corn flavor, DMS does. The yeast may be able to eat up the DMS with any luck


Jovial Monk

 

[wedge]

took a sample to a fellow who knows quite a bit!

He cant even tell, the best he could say was, that something is wrong but what and why..................

Hoping Lagering will remove the flavour