BIAB Mash Time and Boil Time (noob warning)

[Yuz]

I'm planning on another partial BIAB batch, just wanted to clarify - would it be ok to leave the esky for a couple of hours mashing?

From what I've read, BIAB mash time is between 40 and 90 minutes (I've been doing 70 minutes) - would any longer have an ill effect?

Also, these batches being half can / half BIAB - can I reduce the boil time to say 40 minutes for BIAB wort without any adverse effects? I'm boiling in a 12L pot so I'm trying to minimise the evaporation losses and overall brew time...

Thanks

 

[MHB]

An ill effect, maybe both a longer mash and a shorter boil will have an effect.
Same as asking will a shorter or longer steep affect the flavour of a cup of tea, we all know it will whether or not its an ill effect is open to debate.

I wouldn't go shortening the boil, my default is 90 minutes. quite a lot of what happens in the boil is time dependant like SSM > DMS > ejection, the SMM breakdown is a half-life reaction, about half of the SMM will breakdown every half an hour (very roughly, its closer to 37m), so at the end of 30minutes boil you have half the SSM (50%), at 60minutes 25% of what you started with, at 90minutes its 12.5%.
You cant change that process easily or safely, and its all down to how much you can taste DMS and how much SMM was in your malt to start with.
That's just one example, there are more, in another thread I posted some good information on what goes on in a boil, well worth reading
Mark.

 

[MHB]

oops.
Mark

 

[clibit]

I'm doing 30 minute mash and 30 minute boil brews. I know other people have cut their mash and boil times down significantly. Denny Conn is even doing 20/20. And says he is writing a book that will include it.

https://www.homebrewinguk.com/post/30-minute-mash-and-boil-8501821?trail=15&highlight=20+minute+boil

 

[MHB]

Have a read of what Kai has to say "Effects of mash parameters on fermentability and efficiency in single infusion mashing"
Just roughly, it looks like without changing any other mash parameters you loose about ~3-5% mash efficiency (V 60&90minut mashes). and your attenuation limit falls by 5-8% (same times).
So when you get less extract, and finish a few points higher than your recipe calls for, no doubt you will be starting a thread blaming the yeast, the water chemistry or the crush from your HBS - anyone and anything but the decision to half the mash time.
Mark

Oh - I had a play with the raw data at the bottom of the article, cant post an excel spreadsheet but here is a Snip

 

[clibit]

I'm not getting less efficiency, or higher gravity finishes. That's my experience. I was surprised. Denny has said the same. I'm looking forward to his book coming out later this year. It's a bit much saying I will blame anything but the real cause. How do you know I would do that?!

 

[MHB]

Based on experience!
There are lots of things you can do in brewing, but what people forget is that there is always a consequence.
Whether it is enough to affect what you think of your beer is perhaps a different question, but someone (say a beer judge) tastes your beer and goes "a bit hazy -one" "not really clean finishing -another point or two" "Touch of DMS, not to style -another one"... Pretty soon a good solid beer is out of the running.
If you have ever read the response to comps, you will see lots of whinging about how poorly peoples beer has done compared to what they expected, how it went in a local comp, the state comp.

Seriously people forget the law of unintended consequences - everything you do ends up in the glass, choose the cheapest malt V the best malt for a job (i.e. Belgian Pilsner when making a Belgian Triple) it wont taste the same, not saying it will taste bad, just less like the beer you are modeling.
Badly adjusted mills give you lower yields. You have to buy more malt to reach the same OG, lautering will be slower (or too fast), you may well get more tannins as the husks are shredded more...
Shorten the mash time, you will have a higher proportion of unfermentable dextrins, (can be measured)
Shorten the boil, you wont (can't) get the SSM>DMS>Removal that you get at a longer boil, you will get more DMS. Whether or not that matters to you is again a different question, but you will have more DMS.
You wont get the optimum removal of high molecular weight protein, which will affect clarity, mouthfeel and stability (not might will - in measurable ways)
Pitch less yeast - well we could go on but why.

If you think shortening your mash and boil wont have an effect on your beer you are wrong, it will. The only question is whether or not its going to affect your drinking pleasure (which becomes a question about your palate).
If the only beer you want to make is IAPA where you cant taste anything other than hops, well you will probably get away with it.

Locally I have about half a dozen commercial breweries that I'm familiar enough with to say with confidence that they all mash and boil for 60+ minutes and mostly boil for 75-90 minutes.
Is it reasonable to think that professional brewers at least double the mash/boil time because they are all stupid/ignorant, or that they know the benefits and are prepared to invest the time and money to make better beer?

Worth noting that wort boiling is the biggest energy consumer in brewing, if it was possible to make good beer with half the energy cost - do you really think no one in the industry would have noticed.

 

[Yuz]

MHB, makes sense. However, I'm somewhat limited in terms of hardware and space - hence the question.
ATM with one hour boil I end up with about 9L of BIAB wort (losing up to 2L), this gets mixed up with a can of Coopers Lager and chilled water to make a 28L batch. Obviously not a "proper" way to brew but still end up better than a K&K approach

 

[MHB]

It doesn't matter how much you reduce the volume in the kettle (well within reason obviously), you just make it up with more water when you do your kit dilution. The extract is still in the kettle, its just in less water.
Takes the same hardware and space, the only thing that changes is the time you boil.

Coopers have an interesting brewhouse, they have 2 mash mixing tanks (one when I was there last), a Mash Filter and 2 Kettles, one is a smaller kettle where the hops are boiled in a small volume of wort, the other is a stirred high efficiency kettle and a Whirlpool (this is from memory of a tour nearly 10y ago), I think the main wort boil was only 45 minutes, the hop boil was I think 60 minutes before its pumped over to the main kettles.
They can do 12 brew a day (I think they run on 10/d as standard) at about 100% brewery efficiency.
It is possible to do shorter boils, but if you aren't willing to sacrifice quality it requires huge investment in equipment, have a look at merlin wort strippers ($M and up).

60/60 is regarded as short mash/boil, read any good book from only a decade or so and 90/120 minute was regarded as "Standard". You can get good results with shorter cycles (remember that 50-75 years ago a 400 minute cycle was the norm). What has changed is the malt quality, the breads of malt we have, the precision and consistency of the malting.
Weyermann Premium pilsner has a coarse/fine difference of less than 1%, 20 years ago that would have been viewed with suspicion, brewers would have been asking if the malt was over-modified. The brewing equipment has also improved.

Make better beer if you do it properly.
Mark

 

[yankinoz]

I'm planning on another partial BIAB batch, just wanted to clarify - would it be ok to leave the esky for a couple of hours mashing?

Couple of hours mashing no problem, but why use an Esky for a BIAB partial mash? One of the handy things about BIAB is that you can do it in the kettle. I drop mine in a box lined with earth wool, which saves calculating temperature loss. Or does your kettle go in a big Esky?

If you do step or Hochkurz mashes, having the bag in the kettle facilitates heating, but make sure there's a colander ring or somesuch in the bottom to prevent scorching the bag.

Thanks

 

[Yuz]

Well, there's no need to insulate the pot or setup false bottom of sorts with the Esky.
Less to clean up and since I'm still learning I'm taking baby steps... Here's my 13L "mash tun" lol

 

[DrewCarey82]

So its a good idea to increase my mash time to 90 mins?

 

[clibit]

60/60 is regarded as short mash/boil, read any good book from only a decade or so and 90/120 minute was regarded as "Standard". You can get good results with shorter cycles (remember that 50-75 years ago a 400 minute cycle was the norm). What has changed is the malt quality, the breads of malt we have, the precision and consistency of the malting.
Weyermann Premium pilsner has a coarse/fine difference of less than 1%, 20 years ago that would have been viewed with suspicion, brewers would have been asking if the malt was over-modified. The brewing equipment has also improved.

Exactly. Mash and boil times required have continued to fall.

 

[wide eyed and legless]

Exactly. Mash and boil times required have continued to fall.

If you want to decrease the time and don't mind the quality cut out the boil all together.

 

[MHB]

Exactly. Mash and boil times required have continued to fall.

You ignore the part about $million brewhouse to achieve shorter boils without giving up quality at your peril.
Fortunately I don't have to drink your output.
Mark

 

[citizensnips]

Mash time is also relevant to mash temperature. Look into it.

In my opinion you can shorten your boil to 45 mins when using quality (most) fully modified malt as well as maintaining a rolling boil. The importance of maintaining a quality boil is just as important as the length of time, do some research. Also The volume of DMSP in most modern day malts is very low so the likely hood of ending up with DMS in your beer is low if you maintain a good boil.

My 2c

 

[garage_life]

My 2c is do it right, then do whatever the hell you want if your just a home gamer, learn the differences the variable makes and then you have some fist hand knowledge on the subject to make better decisions. Time is always the enemy I guess so use it wisely. I didn't know about the extended times from the older brewing techniques. A lot of the recipes I've looked at of clones and styles I like often have 75+ boils, first wort hops etc. No one's wasting time if they don't have to I guess.

 

[clibit]

Wow. A fair amount of aggression and condescension evident. Can't we have a civilised discussion? Seriously? Disagree, by all means.

If Denny Conn is doing 20 minute mash and 20 minute boils, and is very happy with the results, maybe you could take it up with him? Would you drink his output?

 

[Chap]

Fact is, taste is subjective. And like MHB said, everything you do ends up in the glass. If you’re happy with your results and it works for you, awesome.
I’m no pro, and I’d drink anyone’s brew if it tasted good. Point is if it’s being submitted to competition or being judged based on particular guidelines, it’d be found out pretty quickly for reasons already mentioned.
But again, I’ve taken shortcuts to get a brew down and ready for an occasion (luckily for me they’re all swill drinkers and couldn’t taste an ipa from a stout). Taste is subjective. If you like your product then go nuts

 

[Yuz]

Gentlemen, I wasn't meaning to start a shitfight, but for the purpose, and as a compromise, I will do an hour and a half mash in the esky and a 40-minute boil. Pale Ale base malt and some Crystal. I will then ferment it, and in time - drink it. Good? Done