Iodine Off Flavour

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Hi all, have a terrible off flavour in a dark Vienna pseudo lager I brewed a week ago... recipe below:
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I sparged with a 5L jug which was 1.5 L of boiling water and the rest hot tap water (which is not very hot in this property). the sparge was 12 L and I did the first two as described and the final 2 litres was mostly boiling water, so this may have caused tannin extraction... Lesson learned.

However the off flavour in the beer does not what taste like what I've read derives from a hot sparge.
This is a back of the throat very unpleasant iodine flavour. It was there after the boil so I can rule the yeast out.

Google suggests two sources for that particular off flavour:
1. iodine sanitisers - I used the kegking Stellarsan and no differently than I would any other batch.
2. Chloromines in brewing water. Given Melbourne's excellent water quality and low treatment this was not something I would have suspected.

The ferment seems to have slowed maybe stalled at 1.016 is there any hope of the yeast cleaning this flavour up?
Dump or persevere?

Any thoughts?
 
If it's a medicinal detol type flavour I would suggest chloraphenol which comes about from either Chlorine or Chloramine.

Melbourne water is not generally chloraminated (its less effective than chlorine but lasts longer) however after the recent water quality scare they may have bumped up the chlorine in the supply pending big storms etc.

Once you have the compounds in the beer I am sorry to say but its there for good. If its unbearable you will probably have to dump it. Others may have ideas but I'm at least 7% sure its not a recoverable flavour.

The best treatment is prevention. Use a little Potassium Metabisulphate (KMeta) in your brewing water. Add it before mashing in, the effect is almost instantaneous. It will remove both Chlorine and Chloramine from the water, as well as scavenge some free oxygen from the water.

I use about 0.15g in 30L but if you don't have scales that accurate get yourself some Campden tablets. 1/2 tablet will do a full batch including all mash and sparge water (should do up to 50L)
 
If it's a medicinal detol type flavour I would suggest chloraphenol which comes about from either Chlorine or Chloramine.

Melbourne water is not generally chloraminated (its less effective than chlorine but lasts longer) however after the recent water quality scare they may have bumped up the chlorine in the supply pending big storms etc.

Once you have the compounds in the beer I am sorry to say but its there for good. If its unbearable you will probably have to dump it. Others may have ideas but I'm at least 7% sure its not a recoverable flavour.

The best treatment is prevention. Use a little Potassium Metabisulphate (KMeta) in your brewing water. Add it before mashing in, the effect is almost instantaneous. It will remove both Chlorine and Chloramine from the water, as well as scavenge some free oxygen from the water.

I use about 0.15g in 30L but if you don't have scales that accurate get yourself some Campden tablets. 1/2 tablet will do a full batch including all mash and sparge water (should do up to 50L)

Cheers, never had an issue with Melbourne water before, but yes, I don't want to dump another batch, so makes sense to take precautions.
 
StellarSan isn't Iodine based so you can probably rule that one out.
Chlorophenols are always a possibility, any municipal water will have enough Cl or Chloramine to cause noticeable harm, they need to to insure the water arrives at your tap bug free or relatively so.

Tannin extraction will always occur if you sparge over 80oC. Whether or not its enough to 'Ruin your beer is questionable.
Alkaline sparge water will increase tannin extraction, large sparges say over 1/2 of your total mash water, poor sparging technique (usually means channeling (a lot of the water going in one direction not all going through evenly)) and over sparging (trying to get too much extract) will all give you mor tannin extraction

When it comes to off flavours it isn't all ways just one thing, it could be a bit of Chlorophenol and a bit of Tannin acting together making something not too tasty.
There are a couple of infections that can throw some very nasty flavours, again sometimes they can interreact with other flavours.

Not really treatable (sorry)
Hard to tell what your L:G is as you haven't given batch size which would help

Best option is to treat all your brewing water (plus a bit just incase), I normally filled an HLT the night before add (as above) Met if you aren't carbon filtering all my salts and some acid (lactic) by brew time there wont be any Cl and probably very little O2 in the water, these days using Baumeister's I fill the BM do the same then run off some water to what will be the no-chill cube before mashing in, water in the cube for sparging, wort dilution, toping up kettle if evaporation is a bit high...

Kveik is an interesting choice for a Lager pseudo or otherwise
Mark
 
StellarSan isn't Iodine based so you can probably rule that one out.
Chlorophenols are always a possibility, any municipal water will have enough Cl or Chloramine to cause noticeable harm, they need to to insure the water arrives at your tap bug free or relatively so.

Tannin extraction will always occur if you sparge over 80oC. Whether or not its enough to 'Ruin your beer is questionable.
Alkaline sparge water will increase tannin extraction, large sparges say over 1/2 of your total mash water, poor sparging technique (usually means channeling (a lot of the water going in one direction not all going through evenly)) and over sparging (trying to get too much extract) will all give you mor tannin extraction

When it comes to off flavours it isn't all ways just one thing, it could be a bit of Chlorophenol and a bit of Tannin acting together making something not too tasty.
There are a couple of infections that can throw some very nasty flavours, again sometimes they can interreact with other flavours.

Not really treatable (sorry)
Hard to tell what your L:G is as you haven't given batch size which would help

Best option is to treat all your brewing water (plus a bit just incase), I normally filled an HLT the night before add (as above) Met if you aren't carbon filtering all my salts and some acid (lactic) by brew time there wont be any Cl and probably very little O2 in the water, these days using Baumeister's I fill the BM do the same then run off some water to what will be the no-chill cube before mashing in, water in the cube for sparging, wort dilution, toping up kettle if evaporation is a bit high...

Kveik is an interesting choice for a Lager pseudo or otherwise
Mark

Thanks Mark,
appreciate the advice!

I wouldn't think it was an infection as it was immediately apparent after the boil.

Using a Guten 40L with 22L of mash water and 12 of sparge to get 25L into the fermenter.

Guess dumping is the outcome :(


I've used Oslo for a couple of attempted VB style =pseudo lagers, in an attempt to get my brother in to the hobby (he only drinks VB) and it does produce a clean beer, though seems to leave the beer a little dry to be comparable to that VB sweetness.

Guess dumping the v is the outcome. :(
 
Sux to lose a brew, but better than drinking ugly beer.
I would look at your sparge water treatment, all brewing liquor must be de-chlorinated, carbonate/bicarbonate will really ramp up tannin extraction as will being too hot, Chlorinated, Alkaline and too Hot is really asking for trouble.

If you want a bit more sweetness (maltyness) you could mash a little warmer say 67-67 or get some of that corn out of the grain bill, it tends to promote very light dry beers (mostly used as a protein dilutent), personally I would replace it all with a decent ale malt, the BB you are using would do.
Mark
 

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