Shorten the boil?

[doug293cz]

The big drivers of DMS precursor (SMM) levels are the variety of barley used (higher nitrogen correlates to higher SMM produced, 6-row produces more than 2-row, etc.) and the degree of kilning, i.e. more kilning dives lower levels of SMM. These factors are pretty widely known.

But modification is not the same as kilning, and higher modification doesn't correlate (positively) with low SMM levels. https://www.tandfonline.com/doi/abs/10.1094/ASBCJ-45-0053?journalCode=ujbc20

According to the abstract:

"High barley protein content and good modification during malting were shown to increase levels. Indexes of malt modification revealed barleys that produced low levels of SMM under a given set of malting conditions were inferior in terms of modification."​

​

So, higher levels of modification increase levels of SMM, all else being equal. This is appears to be the opposite of what many people assume.

Brew on

 

[VikeMan]

So, higher levels of modification increase levels of SMM, all else being equal. This is appears to be the opposite of what many people assume.

For some reason, a lot of people think of modification and kilning as the same thing, and I suspect that's where the confusion originated.

Another good read on DMS (that's not behind a paywall) that gets into all the factors, is a 1982 paper by Charlie Bamforth, "DIMETHYL SULPHIDE—A REVIEW":
https://onlinelibrary.wiley.com/doi/epdf/10.1002/j.2050-0416.1982.tb04101.x

 

[Sammy86]

The big drivers of DMS precursor (SMM) levels are the variety of barley used (higher nitrogen correlates to higher SMM produced, 6-row produces more than 2-row, etc.) and the degree of kilning, i.e. more kilning dives lower levels of SMM. These factors are pretty widely known.

But modification is not the same as kilning, and higher modification doesn't correlate (positively) with low SMM levels. https://www.tandfonline.com/doi/abs/10.1094/ASBCJ-45-0053?journalCode=ujbc20

Interesting, can always count on you @VikeMan to drop some knowledge! Thanks for the info!

 

[BeerHolic]

Hi,

I brewed a Dry Irish Stout today - Brewfather - and boiled 30 minutes as suggested at 10m45s here:

Thinking about shortening the boil from 60 to 30 for this: Electric Pale Ale ... hop additions start late in the boil at 20 minutes. Is it a good candidate for a 30 minute boil?

Do you have experience with shorter boil times? What were the results?

I have been doing 45 minute boils for over a 150 brews with no issues, including grain bills with high amounts of Pilsner malt.

 

[landoa]

I did a 30 minute mash 50/50 Pilsner to White wheat and had no issues with DMS.

Remember the malt we are using now is highly modified...the sacred 60-90 minute boil for pilsner malt is for better or worse becoming defunct.

You did a 30 min mash and/or 30 min boil?

I thought the DMS issues were uniquely related to length of boil.

 

[cubalz]

I have done many 20-minute boils with no ill effects. I still do a full 60 for my pilsner recipes where most, if not all of the grist is pils malt due to SMM

 

[Sammy86]

You did a 30 min mash and/or 30 min boil?

I thought the DMS issues were uniquely related to length of boil.

Both, no issues.