60 min vs 90 min boils

[Pennine]

Thank you. A sensible and reasonable discussion, rather than a rant that other people are wrong


Wort concentration can be important for some cases. Other people can get the same result by just adding more grain. Both are equally valid approaches, and cost/time may vary depending on your situation.


This is something I've not witnessed, because I haven't repeated the same brew and done side by side comparisons, though have heard about it. Can you describe the difference between "mild" and "harsh" bitterness in more detail? I find all bitterness harsh. How does the bitterness change as you boil (and can you say how I can appreciate it without sending me comparative samples)?


Others have different experiences (which doesn't make yours or their's "wrong" or "bad advice for beginners"). I have a feeling your altitude means the coagulation takes longer time because your boil is at a lower temperature. This seems to agree with both the respected science and the wealth of empirical evidence. I have noticed that homebrewers (on average) boil a lot harder (volume for volume) than commercial breweries, so wonder to what effect the coagulation/drop-out/clarifying happens faster at the homebrew scale, so the full 60/90 minutes isn't as necessary at these harder boils. It's something I haven't found an answer to, and could help explain why homebrewers experiences (which shouldn't be discarded out of hand) differ from the experiences/practises/advice from pro-setups, where they brew in much larger volumes


Agree. DMS seems to be a non issue for homebrewers these days, even at a 30 minute boil. I've only heard of people warn of it from brewing texts, rather than first hand experience.

Does anyone know when the oft-quoted "modern malts" came into being? I have no idea, and can't find anything. Was it in the last 5 years? 10? 50?

About the bitterness a simple way to describe it for me is one that lingers more and it seems fuller. A shorter boil makes the bitterness effect fade quickly, I also notice more fruity aroma and flavour with shorter boils.

By modern malts I take it to mean new varieties that are grown and more consistent malting processes.

But honestly I have no idea though and should stop parroting until I do.

I do accept some of the findings from brulosophy as they are likely the closest process wise to what I would experience as a homebrewer. If they have measured and find no DMS present after 30 min it's likely accurate.

Also from Scott Janish's DMS page I am pretty sure we are all overpowering our boils and likely most DMS is boiled off quicker than we imagine. This is just an assumption though.

http://scottjanish.com/how-to-prevent-dms-in-beer/
The vigor of a boil also contributes to final DMS levels in beer. One study looked at the power input of a boil and the impact on DMS. The authors found that the when the power input used for boiling increased, the levels of DMS decreased (in a DMS water solution). During a 60 minute boil almost no DMS was detected at 1,500 watts where at 1,000 watts approximately 175 ppb of DMS was detected. At 500 watts, about 300 ppb of DMS was detected.

 

[Pennine]

What I don't understand is why so many believe whatever breweries do is what homebrewers should do? I'd much prefer to rely on other homebrewers experience that brew with similar parameters to me than thinking a 1,760l brewery batch would act similar to my humble 10l batch.

 

[Agentgonzo]

If they have measured and find no DMS present after 30 min it's likely accurate.

I didn't realise that they actually measured it in a lab as well as doing their perception tests: Update: Lab Data on Pils Malt Boil Length exBEERiment

 

[Sadfield]

If they have measured and find no DMS present after 30 min it's likely accurate.

I didn't realise that they actually measured it in a lab as well as doing their perception tests: Update: Lab Data on Pils Malt Boil Length exBEERiment

I think the no DMS in both samples could show that fermentation removed DMS in both, rather than there was none after the boil. In most cases I think homebrew evaporation rate does answer the question more than boil duration. What I do find interesting is the blue and red lines in the small snapshot of the chromotagram do not track, and it would be interesting see the full graph and what the peaks represent. Clearly boil length does make a difference in some of the other peaks.

for

SMM levels would be interesting to see, as it would have a direct impact on DMS produced after the boil. My concern is when the advice for short boils go hand in hand with advice on long hop steeps at c80C.

 

[Beerwegoagain]

When I do my washing I always press the quicker wash button,
Is that ok ??

Possibly...if it comes out clean yes if not wash quickly again?
DMS in this case stand for Dirty Man-Sock? (no offence)

 

[Cheshire Cat]

I think the no DMS in both samples could show that fermentation removed DMS in both, rather than there was none after the boil. In most cases I think homebrew evaporation rate does answer the question more than boil duration. What I do find interesting is the blue and red lines in the small snapshot of the chromotagram do not track, and it would be interesting see the full graph and what the peaks represent. Clearly boil length does make a difference in some of the other peaks.

for

SMM levels would be interesting to see, as it would have a direct impact on DMS produced after the boil. My concern is when the advice for short boils go hand in hand with advice on long hop steeps at c80C.

Have you ever done a short boil?

 

[Sadfield]

Yes thanks. @Cheshire Cat

.... and no boil..... and 120 minutes boil....all valid methods......all different.

 

[Cheshire Cat]

And?

 

[Sadfield]

And?

Not necessarily. For me short boils are a bit bland. I bit like making toast, if it's barely colours it just tastes of hot bread.

Less depth of flavour, less colour development. Less stability in flavour over time.

 

[Sadfield]

Would you expect the same outcome between.....

Brewing tea for 1 minute and 2 minutes?

Grilling a steak for 5 minutes and 10 minutes?

Heating sugar syrup to make brewers invert sugar for 45 minutes and 90 minutes?

Or, Cooking an oxtail stew for 2 hours and 4 hours?

Why would wort behave differently and remain unchanged when the applied thermal energy is doubled?

Why is discussing any difference viewed as an attack on one particular arbitrary time?

 

[foxy]

I think the no DMS in both samples could show that fermentation removed DMS in both, rather than there was none after the boil. In most cases I think homebrew evaporation rate does answer the question more than boil duration. What I do find interesting is the blue and red lines in the small snapshot of the chromotagram do not track, and it would be interesting see the full graph and what the peaks represent. Clearly boil length does make a difference in some of the other peaks.

https://www.researchgate.net/public..._delayed_onset_of_boiling_during_wort_boiling

 

[Agentgonzo]

Also from Scott Janish's DMS page I am pretty sure we are all overpowering our boils and likely most DMS is boiled off quicker than we imagine. This is just an assumption though.

This is what I've been thinking for a while now. Compare photos of the surface of boiling wort from commercial breweries and homebrew.*

I've started (in the 6-12 months) reducing the power of my boils so that it's not on full tilt anymore. This, combined with a partly covered kettle, results in the necessary amount of aggitation/rolling in the boil but with the huge advantage of my utility room not ending up like a sauna with water dripping down the walls.


* You can also do a simple comparison of boil-off rates, which are normally a lot higher in homebrew than commercial. And you can also just look at the power input and wort volumes if you can get figures. Just looking at the Four Priests YouTube vids, @chopps uses a max (often less, maybe under half of this value) of 4 (16 amp) elements in 7 firkins (from memory) of wort. Which is 14.7kW in 286L, or 50W/L homebrew is a single 13A element (3kW) in (typically) 30L, or 100W/L.

And that's for electric. Those on propane get MUCH higher heating

 

[Sadfield]

And that's for electric. Those on propane get MUCH higher heating

Where does that extra thermal energy go? What effect does it have on all the compounds other than dms in wort?

 

[Weizenberg]

The low surface to volume ratio of our vessels should make DMS expulsion more efficient than considerably larger vessels.

Shame they did bit measure the effects if power and boil length on the Thiobarbituric Acid Index (TBI). I would expect thermal stress to vary significantly.

 

[Weizenberg]

Same here. I reduced boil time from 90 to 60 to reduce thermal stress (slightly brighter) and a small bump in body.

It is a lot more noticeable in pale brews.

I also experimented reducing the intensity (power) during boils.

 

[Philthebrewer]

https://www.researchgate.net/public..._delayed_onset_of_boiling_during_wort_boiling

thanks for the link, Foxy, which sent me down the rabbit hole of citations. It seems that there has been a fair amount of research on DMS. The research seems to be trying to answer the question of how much can you reduce power and still achieve a removal of most of the DMS. The focus is on commercial brewing with methods like "delayed onset of boiling" and reduced current boil (where a boil is defined as low as 95 degrees).

As others have commented, we little people in the land of 10 to 50 litre batches throw lots of power at our boils, achieve 99 or 100 degrees and a good rolling with lots of evaporation. It is not surprising if the removal of volatile compounds such as DMS is accelerated in home brewing under these conditions.

Great thread, thanks all. I for one will keep experimenting

 

[foxy]

thanks for the link, Foxy, which sent me down the rabbit hole of citations. It seems that there has been a fair amount of research on DMS. The research seems to be trying to answer the question of how much can you reduce power and still achieve a removal of most of the DMS. The focus is on commercial brewing with methods like "delayed onset of boiling" and reduced current boil (where a boil is defined as low as 95 degrees).

As others have commented, we little people in the land of 10 to 50 litre batches throw lots of power at our boils, achieve 99 or 100 degrees and a good rolling with lots of evaporation. It is not surprising if the removal of volatile compounds such as DMS is accelerated in home brewing under these conditions.

Great thread, thanks all. I for one will keep experimenting

Well it isn't about, reducing DMS more on the precursor of SMM leading up to the boil. The way science is taking us is towards brewing with none malted grain we wont have to worry about DMS.

 

[Sadfield]

Same here. I reduced boil time from 90 to 60 to reduce thermal stress (slightly brighter) and a small bump in body.

It is a lot more noticeable in pale brews.

I also experimented reducing the intensity (power) during boils.

Is reducing thermal stress always beneficial though? From a technical perspective, yes. However if a brew was traditionally done with a long, vigorous boil, does thermal stress and its affects become part of its flavour profile?

 

[Weizenberg]

Is reducing thermal stress always beneficial though? From a technical perspective, yes. However if a brew was traditionally done with a long, vigorous boil, does thermal stress and its affects become part of its flavour profile?

I'd treat it as a possible lever.

To which extent, is up to the bewer.

It does have a flavour impact. I'd imagine that eventually it might turn negative. I doubt this would happen within generally accepted ranges.

 

[Agentgonzo]

I would expect thermal stress to vary significantly.

What exactly is "thermal stress", and what happens (from a chemistry point of view) that affects the beer?