Serious DMS in Czech Lager

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carter840

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Well I have a Lager on tap now with some serious off taste, I thought it was oxidation, but I just got some comments back from a local competition and both judges said they got a lot of DMS. Now that I have read about it I agree that DMS is my problem with this batch. From what I have read DMS is a larger problem in pilsners because of the ingredients, and also because DMS is more perceivable in a light flavored beer like a lager. I read that allowing for a strong boil and not covering the beer is the proper solution as well as proper cooling.

Here is my issue: I brew on an electric stove!

I often need at least partial coverage on my kettle to keep a boil going. Has anyone found a method for reducing DMS in situations like mine. I am thinking about a kettle lid that somehow absorbed the water vapor rather than letting it drip back in the kettle. A long boil also seems like a possibility.

Thanks
 
Yup DMS can be prevalent in those style beers and because they are so light there is really nothing to hide the off flavor. To prevent DMS you really need a vigorous boil, no lid and some recommend a 90 minute boil as well.

If you cannot achieve these things on your set up then you either need to adjust your set up to account for these pitfalls or not brew this style of beer until you can account for it's production requirements
 
Yup DMS can be prevalent in those style beers and because they are so light there is really nothing to hide the off flavor. To prevent DMS you really need a vigorous boil, no lid and some recommend a 90 minute boil as well.

If you cannot achieve these things on your set up then you either need to adjust your set up to account for these pitfalls or not brew this style of beer until you can account for it's production requirements

So lets make this a hard reality. Not brewing pilsners if alright, but honestly I'd like to try for a solution before I completely disregard light lagers altogether. So maybe there is a way we can think of a solution. For example a longer boil going from 60 minutes to 90. Perhaps putting a lid on but allowing a 1/4" gap around the entire perimeter and slanting the lid so that condensing vapor does not fall back in the kettle.
 
The thing about DMS is it has to be boiled off and most people insist on a 90-120 minute hard boil. I'm not aware of any other way of getting DMS out than hard boiling for a long time. I'd be interested in hearing what others post though.
 
You do 5 gallon batches on the stove? That has to take for ever to bring to a boil. Get a propane burner and your DMS problem is solved.
 
If you can't do propane, you can split your batch into 2 pots to reduce the volume to something your stove can handle.
 
You can put a partial lid on, you just have to rig it so that the condensing water drips off to the side instead of back into the pot.

You can certainly boil longer to try to make up some of the difference.

You can pitch a lot of healthy yeast to have a more vigorous fermentation. The CO2 drives off DMS just like a boil.

You could do half batches or split your boil up so you aren't heating as much wort.
 
Cooling it quickly is also important after the boil, as DMS keeps being produced while the wort is hot. So if you're not boiling, you're adding DMS (until you get below 100 F or something like that)
 
Cooling it quickly is also important after the boil, as DMS keeps being produced while the wort is hot. So if you're not boiling, you're adding DMS (until you get below 100 F or something like that)

And make sure you don't cover the pot during the chill! I think the SMM to DMS reaction stops at 140 or under, so try to get to under 140 ASAP while chilling.

I'd either get two pots and split the boil, or boil outside on a propane burner. That would fix the DMS issue.
 
Look in to getting a 1000 watt bucket heater. I've read that some brewers use them to help the stove along.
 
Sorry to bring this up again but I just had a glass of this lager. It's like drinking corn, simply undrinkable.

Someone mentioned using CO2 to strip the DMS. I know I would switch the CO2 to the dip tube side, but can anyone tell me how much CO2 I need to do this, and what pressure to push through it. The beer is already carbed and is currently cold. I am thinking about just tossing this batch, but if it can be saved...
 
Someone mentioned using CO2 to strip the DMS. I know I would switch the CO2 to the dip tube side, but can anyone tell me how much CO2 I need to do this, and what pressure to push through it. The beer is already carbed and is currently cold. I am thinking about just tossing this batch, but if it can be saved...

That was me. It doesn't take a lot of pressure. Just vent the keg and bubble the CO2 slowly. Honestly, it's been awhile since I tried it, but I remember it seemed like a lot of CO2. There are some other threads on here you can search for, but there wasn't a ton of info on it when I did it. Sorry I can't be too specific. Start with the gas barely flowing for 10-15 minutes, taste, and repeat. I know it took me a couple of sessions to get there.
 
Think of it this way:

The half-life of DMS in a boil is 40 minutes...every 40 minutes of a boil reduces DMS or its precursor by 50%. So a two hour boil will remove 90% of DMS in your beer...a 90 minute boil removes 80%. So there is twice as much DMS in a 90 minute boil as a 120. Seriously, just do a longer and more vigorous boil and you will be in the clear.
 
Think of it this way:

The half-life of DMS in a boil is 40 minutes...every 40 minutes of a boil reduces DMS or its precursor by 50%. So a two hour boil will remove 90% of DMS in your beer...a 90 minute boil removes 80%. So there is twice as much DMS in a 90 minute boil as a 120. Seriously, just do a longer and more vigorous boil and you will be in the clear.

That's fine for the future batches, but right now I have like 4 gallons left of a beer that I have babied and temp controlled for 10 weeks. I was hoping to drink and enjoy it.

I will try to bubble it this weekend and see what happens. In the future all my pilsners will have 2 hour boils.

Also I already do have a propane burner, but i brew in a small apartment in a city. So I can't use it for most of my brews. Looking to get into an electric heating element in the future.
 
That's fine for the future batches, but right now I have like 4 gallons left of a beer that I have babied and temp controlled for 10 weeks. I was hoping to drink and enjoy it.

I will try to bubble it this weekend and see what happens. In the future all my pilsners will have 2 hour boils.

Also I already do have a propane burner, but i brew in a small apartment in a city. So I can't use it for most of my brews. Looking to get into an electric heating element in the future.

I brewed a Czech Pilsner and had the same problem. At the time I was brewing stove-top on an electric stove as well. I ended up chunking the batch:(

For subsequent batches I found that wrapping the kettle in insulation and placing the kettle over two burners helped immensely with getting a decent boil. Brewing smaller batches, doing partial-boils, or using a heat stick will also help.
 
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