20-minute mash, 20-minute boil

[Oliver]

I was talking to a commercial brewer on the weekend who said that for one of his beers (and possibly all - I didn't clarify) he mashes for 20 minutes then boils for 20 mins, with an addition of hops at 20 and a flamout addition that he whirlpools for 15 minutes. He does this to save time and is how he used to brew the beer as a homebrewer, before he went commercial with it.

He told me the recipe and I'm going to give it a shot at some stage - knocking 1-1.5 hours off my brew day is certainly an attractive proposition!

I'm familiar with the concept of such late hopping (hop bursting?), but has anyone tried a 20-minute mash and/or a 20-minute boil and if so what was the result?

Do any of you do it as a matter of course?

Oliver

[weizgei]

I'm guessing many of us will have done 20 minute boils with extract brews, I have a few times. Some people get confused with un-hopped extract, they assume it's been boiled for 60 minutes like a kit extract has been, but my understanding (and I confirmed this with Coopers and Briess a while back) is that un-hopped extract has only been boiled very briefly post-mash, and usually under vacuum so it doesn't even reach 100C. So technically, if you think you have to boil mashed grain for 60 minutes, then you should assume you need to boil un-hopped extract for a similar amount of time.

That being said, there does seem to be a long-held belief (with grain at least) that you have to boil the wort post-mash for 60 minutes or more to drive off volatiles, coagulate protiens, etc etc. But I remember researching this a while back, and it seems it's one of those assumptions that's been challenged successfully by new-world brewers, much like everybody thought you had to chill your wort quickly after the boil...yet now heaps of guys are doing no-chill. From an IBU perspective, with the high alpha hops that are perfectly suitable as late additions, such as Citra, Centennial, Columbus...no reason you couldn't use them in 15/20 minute boil situations to give you the IBU you need, and you have the bonus of all the hop flavour and most of the aroma still being around.

The 20 minute mash intrigues me though...I assume you can't extract the same amount of sugar in 20 minutes as you can 60 (or even 75 if you include a mash-out as I do with BIAB). Does this commercial brewer you spoke to simply increase the amount of base grain he uses to give him his desired pre-boil gravity? i.e. If you'd normally use 4kg of base grain mashed for an hour to get 1.040 pre-boil , how much grain do you need to mash for 20 minutes to get that same 1.040? 6kg? 8kg? Grain is cheap, especially when you're buying it at commercial volumes, I'm guessing he's paying less than $2 per kg....so if it's just a matter of upping the volume to save the time, why not?

Although I'm limited by my equipment, as are you...if you need 50% more grain to get the same pre-boil gravity, wouldn't that be an issue for your 20l braumeister? Or do you just have to brew smaller batches?

Can you post his recipe up for us to have a look?

EDIT: Just spotted this via Google, seems Charlie Papazian himself reckons 20m is enough for good quality malted brewing grain. Wow eh?
http://www.homebrewtalk.com/f36/20-minute-mash-302811/
There's a podcast you can listen to from Basic Brewing that compares the results of a 10m, 30m and 60m mash (the link in the post above is broken, use the one below):
http://media.libsyn.com/media/basicbrew ... shtime.mp3

[emnpaul]

I was given a spec sheet for some Weyermann Pils malt a while ago that claimed conversion in under 20 minutes, might even have been 15 if memory serves me correctly. I did an iodine test at 30 and it was all converted. I still mash for minimum 60 minutes and piss about with step mashes most of the time but I can't see a problem with very short mashes as long as you can confirm that conversion is complete. This is a bit of a generalisation however. I would still expect conversion to take a little bit longer at very low mash temperatures and when using large amounts of adjuncts, but I'm happy to be proven wrong.

Not sure about the boil. I've only ever boiled for a minimum of 60 mins and hadn't heard of anything less than 45 until I read Oliver's post above.

[weizgei]

On the boil, there's a lot of talk around what type of malt can be 'short boiled', the general agreement is that pilsner malt needs boiling longer to avoid DMS, but ale malt is a good candidate for short boil times as it has less of the precursors.