Pilsner dms

For DMS, it can be easier (and cheaper) than that. Get a can of creamed corn. Open. Smell.

 

Does it remind you of celery?

 

I use a lot of Weyermann and I always do a 70 minute boil, but that is in part due to brewing on a commercial system where my boil off rate is only about 6%. With a homebrew system and the large surface area of most boil kettles, if you aren't using a lid, it should be pretty difficult to get DMS.

However, with the increased use of systems like Grainfathers and Robobrews, those normally need the lid to reach a full boil and the hole in the lid is pretty small, making it more similar to a commercial set up with a vent stack. If that's the case, I would do a 70-90 minute boil.

 

Extending your boil duration to 90 minutes is not necessary if you live at a modest elevation or lower. Its the brewers that live at high elevation that MIGHT need to consider extending their boil duration. SMM conversion rate to DMS is temperature dependent. As you probably know, water and wort boil at lower temperature at higher elevation and that can eventually leave your wort with too much SMM and DMS.

The main thing that I find brewers for that have DMS problems in their beer is that they aren't boiling 'effectively enough'. You can have your kettle completely covered during the early stage of wort 'boiling' and actually only have the wort lightly simmering. That converts SMM to DMS just as effectively as a volcanic boil. However, its the late stage of boiling that your kettle must be open and every molecule of your wort needs to have an opportunity to be at the atmospheric interface at the top of the wort. For that to occur, your wort needs to ROLL across the entire surface of your kettle. A haphazard, volcanic boil may not provide you with that. Offsetting your kettle slightly off the center of your heat source can help heat one side of your kettle and that helps promote the rolling wort action. Its not the volcano, its the roll that you want.

Of course, your kettle must be uncovered during the DMS volatilization stage. Its the exchange with the atmosphere that rids the wort of its DMS content.

The final consideration for DMS reduction is to get your wort chilled below 185F as soon as possible when you've brewed with high pils content. Any unconverted SMM remaining in the hot wort has an opportunity to convert to DMS and it isn't going to get the chance to leave the wort since there is little exchange with the atmosphere when its sitting still in your kettle.

For most brewers in the world, the need for a 90 minute boil when brewing with pils malt...is a myth.

 

A comment on Rolling Rock. It was used as an example of DMS when I took BJCP training not that many years ago. It was brewed by ABInbev at that time. The sample had high amounts of creamed corn aroma. Find a bottle or can and try it.

 

I would have guessed that Rolling Rock was primary 6-row malt (at least back in the day) not Pilsner malt, and that the corn aroma was coming from the fact that they actually use corn in the grain bill.

 

Corn aroma can come from things other than DMS, think about a corn tortillas' aroma, it is a corn aroma, but not DMS.

Other breweries used 6-row and corn. RR was said to have process issues in the brewhouse, what I don't know exactly.

 

Jeff, @Peter_Wolfe posted the below in a past thread discussion (a reply to me) with emphasis in bold by me:

“Target for rolling rock, iirc off the top of my head, is between 60-90 ppb (not ppm), and it's usually on the lower end of that (~65-70ish). The limit for all other ABI beers is <10 ppb. The higher level is achieved via a special boiling profile since having a separate malt stream would be really annoying. They (the ABI brewers) actually went to great lengths to "maintain the defect" and not alter the beer profile when they brewed the beer at locations other than the "glass-lined tanks of old Latrobe" or whatever it was that the bottles said.

Threshold for most people is 40-50 ppb, though some talented folks can detect it down to 15 ppb. Most things with a sulfur atom involved have thresholds in the ppb/ppt range as opposed to ppm.”

Cheers!