What are your ways to split up your brew day/s?

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Okay... But is boil time the same for all volumes or can it be adjusted according to surface area/ intensity?

I.e. Do you need to boil 2 litres of wort for 90 minutes?
 
Same for volume, not necessarily intensity. The obvious reasons for boiling for a time period are IBU extraction/conversion, but there are far more important reasons, which effect the stability of the resultant beer. I obtained a useful sheet on the reasons for the boil (on my phone so can post later this evening if MHB doesn't beat me to it).

90 mins is not mandated and 60 min boils are quite common. I think you could get away with an intense 45 min boil, especially if the beer is consumed fairly quickly, but short cuts have consequences.
 
Would be interesting to get lab results for parameters (e.g DMS) and graph them against length of boil for different volumes.
I suspect running 4x 3L intense boils (12L total) would be quicker than doing my current 12-13L 90min boil.

edit: I can run 4 x 3L boils simultaneously (the boil off volume after 10min would be similar to 12L 90 min boil).

Hop additions could be added separately (e.g. dry hop in fermenter) or a small liquid addition.
 
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Here you go. I've thrown in a couple on Beer stabilisation also.
 

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  • 04 - Beer stabilisation part 2.pdf
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  • 01 - Beer Stabilisation part 1.pdf
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Thanks, very interesting read. I shall ponder over it.

It would be nice to see some data (appears missing in above literature) on boil volumes and surface area on chemistry and speed/change of volatiles.

Another technique is potentially not boiling at all, thereby reducing likelihood of precursor molecule to DMS at all. Open fermentation seems also to reduce DMS compared to a conical a few ways to skin the cat it seems.
 
If smm is not transformed and evaporated during the boil, it can be transformed during fermentation and the resulting dms will remain in the beer.

Many, many other good reasons for boiling - colour and flavour development are the two high on my list but wort sterilisation and hop isomeration aren't far behind.

You might get away with 4, hard short boils for gravity, colour and flavour but I believe smm (or dms) has a half life that requires time, regardless of volume. Modern malts have less precursor but with so many good resons for a proper length, I find it hard to be convinced that dropping below 60 is wise.

Not sure how protein coagulation behaves in shorter, intense, low volume boil.
 
Cool but once again I question the "regardless of volume" statement? Where is the data?
 
Cool, but I'd like to read what the experimental procedures were during which the half life was determined? What was the ramp up to temp time, sampling and storage protocols prior to testing?
What volumes of wort (or liquid?). Many possible covariates.
 
There's enough information there for you to do your own research.
You may end up deciding your short boul idea is fine.
 
I just like to see the data rather than dogmatically following a quoted figure who's experimental factors aren't being explained.
If someone has done the reading let us know or I'll try and get up to speed if time allows.
If the data doesn't exist on small volume boils I may find time to run some experiments and submit to the lab at my work.

Edit: This appears to be one of the papers many are quoting. Boil volume is not recorded in the methodology. It was a lager with two malts.

http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.1979.tb06845.x/pdf
 
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So brewed a Tripel using the methods suggested last night.

Setup my 2v HERMS the night before. Put a timer on so that the mash was at strike temp when I got home. Chilled overnight in Melbourne weather and the wort was 22c in the morning ready to pitch. Easy.

Next time though I'll mash in cold, as for some reason my kids don't respond to "you really need to go to sleep now as I have to dough in"?
 
I've got a ton of fresh AG ingredients eating a hole in my pocket... Would pain me to do an extract brew (not that I'm against it).
 
I split my brew day at the boil, I bring the brew to a boil then seal up the kettle and leave overnight or longer, it is sterile at this point and will not go off, when I resume the boil it is sterilized again, it also seems to drop out more hot break this way.
 
This one's methodology is slightly better,volume is provided: e.g. (500 mL) but uses an unidentified 'lager' malt.

However, it also states that the boil was "under reflux" which means that volatiles were not allowed to escape the vessel (no evaporation) so I'm not sure how close to real world that is likely to be. I'm not sure why reflux was used, possibly because boiling such a small volume could not have continued for the time frame of the experiment. However the technique could have influenced the results.

/Dickenson-1979-Journal_of_the_Institute_of_Brewing.
 
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If you're looking to accelerate the reactions in the boil, then it would be worth understanding the reaction kinetics (if anyone's actually done that research; it would be rather difficult). I think what a lot of people in this thread are angling at is: Yes, there is no data regarding boil volume, but the fundamentals of chemical reactions are well understood. Vessel volume does NOT have a direct influence on reaction kinetics. The only way it would affect it is via mass flow characteristics (increased the interaction rate of the molecules from differing boil seeding and convection), which is indirectly. This would only increase the reaction rate if the reaction is indeed limited by the work input. However, like most reactions, my understanding is that the SMM--> DMS is an equilibrium reaction, and that the reaction rate is primarily dependent on temperature. (EDIT: Try a pressure cooker to get a higher temperature and faster reaction?)

While I understand you want to (dis)prove your hypothesis, I believe a more holistic optimisation approach would be better.

Eg, you may find that an external boiler with a kettle pump will give you higher energy efficiency and mimic higher boil intensity due to the far greater turbulence. This is in fact how industrial brewing kettles work (they are often under partial vacuum with vapour recovery too).
 
What it boils down to (yeah nice pun) is that most research is aimed at commercial practices to ensure customers receive the best possible product while production costs are kept as low as possible. If commercial brewers could get a way with shorter boils, which would significantly reduce their energy expenditure, then they would.

Home brew is a different kettle of fish (pushing it with that one) altogether. You can get a way with some shortcuts with home brew and still have acceptable beer.

If you wan tot strive for the best beer you can make, then I wouldn't recommend shortcutting things like boil times. If you want to make acceptable beer in less time to improve your brew/life balance, then I say go for it.

Worse thing that can happen is that the beer is sub par.
 
If your interested in spreading a brew over multiple days, maybe consider over night mash.

Mash in just before bed, set at around 70c, insulate well. Will probably be sitting at about 63c or so in 7-8 hours time. Sparge and boil. You should have a cube filled within 2 hours the next morning.

Fill brewery
Heat liquor
Mill grain
Mash in

Sleep *zzzzzzzzzzzzzz

Sparge
Boil
Cube
Clean

Pitch when your ready.

You can have multiple cubes ready to go too so you can keep your fermenter going. It's easier to find time to pitch as it doesnt take long. Brew when you can, even if you're well stocked because you can never have too much wort ready to go. Do back to back brew if you plan to spend a day brewing.
 
This study doesn't really say much more, except the obvious high temperature = faster breakdown of SMM to DMS:
http://onlinelibrary.wiley.com/doi/10.1002/jib.156/pdf

It also backs up a ~30min half life of SMM at 98.5°C.

It's quite possible that you can exceed 100°C in the lower areas of your kettles, though I think this is more likely in a taller kettle. The additional convection will help big-time with the actual boiloff of DMS though - so my scientificish opinion is that no-chilling with a reduced boil would lead to more SMM hanging around and being metabolised to DMS by the yeast, = bad.

Keep in mind as well that different malts have different amounts of SMM to begin with. Gladfields pils, in a few beers I tasted, seemed to have a heap. A well modified, lightly kilned malt will have the 'most' amount of SMM vs a less modified, darker malt (which has been kilned at higher temperature - the kilning driving off some DMS). So your Weyermann Munich II will have bugger all, whereas some of your extra-pale pils will likely have a lot.

Keep the malt in mind when doing your recipes and you may get away with it. With a pale pils, 30min boil and no-chilling though I KNOW that you will have DMS issues.
 
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