Overnight mashes... pros and cons?

[graysalchemy]

If you mash in a coolbox or other well insulated tun, it's the one bit of the process where you can go and do something else completely for 90 mins or whatever

You are missing the point it takes more than 90 minutes to do a mash you have to heat water its more like 3hrs for me. You also seem to be making the assumption that everyone is doing 23l brew lengths and have a full day to brew, which simply isn't the case.

I brew 55l in my business premises during the normal working day but it is simply too tight to fight it all into one day.

I cannot use a timer to set my heater so it takes approximate 90 minutes to heat up my water so realistically I can't get the mash started before 10.00am.

Mash is 90 minutes, takes me to 11.30 am.

It then takes 1 hr sparging at 1l/min so realistically I cannot get the boil on until 12.30 at the earliest.

Next the boil takes another i hr r to get up to temp so that is 1.30pm before the boil starts. 90 minute boil takes me to 3.00pm.

55L of wort takes approximately 1 hr to cool down to 27c, so I am already at 4.00 pm.

Now that does not take into account 15 minutes here and 15 minutes there between different operations or a stuck mash etc etc.

I still then have to transfer the 55L into the FV (which has in the past with lots of hops take 45 minutes) physically move 55l FV into another room at the other side of the workshop wait till the wort is actually 20c, rig up the coiling coil heater and temp controller, pitch the yeast, oh and tidy up. and do all that before I leave at 5pm to beat the traffic to get home to one of my kids various extracurricular activities. :grin:

 

[Aleman]

I have just changed from overnight mashing with BIAB to a 90 minute mash and 3 vessels. The reason being that I suspect that it produces a more fermentable and slightly thin beer. I've produced wort with a higher OG and lower FG than I would have expected, great for higher ABV beer but I'm after body now.

My reading has suggested that both the looser grist ratio and the long mash might have contributed to the lack of body.

I think that hits it pretty much on the head Nic, the other thing that should perhaps concern us as brewers is the extraction of tannins from the grain. I've heard tell of overnight mashed beers that have a harshness that goes away when mashed for 90 minutes.

Beta Amylase doesn't like thin mashes or high temperatures . . . but just because that is so does not mean that it is destroyed completely, it only takes a low level in an extended mash to thin out the beer/body

Not that the beers have been bad just that they might have been better done another way.

Yet another brilliant observation, if it's working for you . . . don't change it, if there is an issue then change something and see if things improve.

 

[adomant]

Sounds like you have no other option then :thumb: I'm not suggesting you should risk the day by not doing it, but just some thoughts on time saving tips (sorry if they are obvious and you've already tried)

I cannot use a timer to set my heater so it takes approximate 90 minutes to heat up my water so realistically I can't get the mash started before 10.00am.

If I'm in a hurry, I'll just heat the mash liquor volume in the HLT and heat the sparge liquor while the mash is on.

It then takes 1 hr sparging at 1l/min so realistically I cannot get the boil on until 12.30 at the earliest.

can't cut down sparge time, but could start the boil with first 20 litres and add in installments to get boil started faster

Next the boil takes another i hr r to get up to temp so that is 1.30pm before the boil starts. 90 minute boil takes me to 3.00pm.

If a rolling boil is achieved then 60 minutes boil from there would be fine

55L of wort takes approximately 1 hr to cool down to 27c, so I am already at 4.00 pm.

I'm guessing there are water supply / run off issues in your premises which rule out a wort chiller ?

 

[graysalchemy]

If I'm in a hurry, I'll just heat the mash liquor volume in the HLT and heat the sparge liquor while the mash is on.

That is what I do

can't cut down sparge time, but could start the boil with first 20 litres and add in installments to get boil started faster

And I already do that

If a rolling boil is achieved then 60 minutes boil from there would be fine

Disagree there 90 minutes to secure the hot break there has been a lot of discussion on that recently, I am not going to compromise the clarity of my beer for shorter boil times.

I'm guessing there are water supply / run off issues in your premises which rule out a wort chiller ?

Why would you think that, that is with 15m of 8mm copper wort chiller going with the water supply first running through a maxi 310 in summertime.

 

[markmark]

Aleman beat me to the point.....but I think I have fallen out with overnight mashes due to tannin extraction.
The last beer I made I had to throw away.....all 40 litres of it
The only thing I can tie it down to is overnight mashing and an inclusion of crystal malt (I rarely use crystal malt).
Some other overnight mashes have been acceptable, but like others have mentioned....the lower FG can thin out what would otherwise be a great beer.
I won't be brewing again until after Christmas, but it will be the timer switching on the HLT and an earlier start for me from now on.

 

[morethanworts]

If you mash in a coolbox or other well insulated tun, it's the one bit of the process where you can go and do something else completely for 90 mins or whatever. I'm only on AG3, so I still make use of that time checking what I'm doing and making sure everything is ready for for the sparge onwards.

I can't see where I'd save much time by overnight mashing. I guess the brew day itself would end an hour or two earlier, but the mashing in etc would have been time spent the previous evening, and the mash time itself is time I can use anyway.

:thumb: I guess it depends on your own schedule.

It's the sparge onwards that I need to get much shorter myself.

You are missing the point it takes more than 90 minutes to do a mash you have to heat water its more like 3hrs for me. You also seem to be making the assumption that everyone is doing 23l brew lengths and have a full day to brew, which simply isn't the case.

I brew 55l in my business premises during the normal working day but it is simply too tight to fight it all into one day.

I cannot use a timer to set my heater so it takes approximate 90 minutes to heat up my water so realistically I can't get the mash started before 10.00am.

Mash is 90 minutes, takes me to 11.30 am.

It then takes 1 hr sparging at 1l/min so realistically I cannot get the boil on until 12.30 at the earliest.

Next the boil takes another i hr r to get up to temp so that is 1.30pm before the boil starts. 90 minute boil takes me to 3.00pm.

55L of wort takes approximately 1 hr to cool down to 27c, so I am already at 4.00 pm.

Now that does not take into account 15 minutes here and 15 minutes there between different operations or a stuck mash etc etc.

I still then have to transfer the 55L into the FV (which has in the past with lots of hops take 45 minutes) physically move 55l FV into another room at the other side of the workshop wait till the wort is actually 20c, rig up the coiling coil heater and temp controller, pitch the yeast, oh and tidy up. and do all that before I leave at 5pm to beat the traffic to get home to one of my kids various extracurricular activities. :grin:

I think you've made the assumption that I was making assumptions! I was talking about my own timings and set up really and I did say in my first post that it would save an hour or two on brew day.

If I may though, adopting the brace position, it sounds like a good time saver would be to throw a few more kW at the HLT and at getting from sparge to boil, if you're going to do batches of that size, costs permitting. Better than the thin or tannin heavy beer that others are concerned they've had from overnight mashes. I recall PD recently having a Black Sheep clone go down to some unexpected FG after an overnight mash, though I think he still liked the beer. I reckon my heating-up times are half to a third of those and my cooling time has been around 25mins to 18C from flame out.

Yes, I do 23L batches or so. I guess there is a batch size/frequency of brewdays/size of production wanted/equipment costs balance. Maybe it depends on all those factors.

 

[graysalchemy]

My point MTW was regarding your comment which i highlighted in my post and you seem to have missed out.

I am quite happy with my beers I have no issues with tannins in them and the thinness is related to not reaching a high enough mash temp due to the cold nature of where I work and brew.

And yes it does certainly take longer to brew a larger batch of beer but much shorter than brewing two separate 23l batches.

 

[morethanworts]

Well I don't know what you mean I've missed out - I deliberately copied the whole quotes so as not to - but you've been helpful to me in the past, so I'm not going to get any more defensive about it!

And yes it does certainly take longer to brew a larger batch of beer but much shorter than brewing two separate 23l batches.

Most things are scalable, but two shorter batches would certainly take longer. I can see it's worth burning the candle at both ends a bit sometimes. :thumb:

 

[gl0ckage]

So I mash for 1 hour in my biab setup. I made a stout and added Malton dextrine but it feels like water. The brew I did a few days ago was mashed for 2 hours with carapils and around 66 Celsius.

So why is my brew watery if what your saying is I shouldn't have a light body if I mash for a short time?

 

[rpt]

So I mash for 1 hour in my biab setup. I made a stout and added Malton dextrine but it feels like water. The brew I did a few days ago was mashed for 2 hours with carapils and around 66 Celsius.

So why is my brew watery if what your saying is I shouldn't have a light body if I mash for a short time?

What was the gravity?

 

[jonnymorris]

So why is my brew watery if what your saying is I shouldn't have a light body if I mash for a short time?

You need to mash long enough to extract the sugars but potentially not too long so as to make your wort too fermentable (not that I've noticed the latter being a problem).

You want more body... mash higher than 66degC.

 

[rich27500]

My mash starts at 68c and will drop into the 50's over 8 hours. Typically I will get at least 1.050 from a 5kg grain bill for a 23l brew length. My FG rarely goes under 1.010. Never had thin watery results. The BIAB forum will tell you grist ratio is a myth. I doubt that because commercial brewers are so convinced about it. I suspect at 23l it's not an issue. For the 'stat that counts' I'm consistently told I make nice beer.