Mashing Out

[boozy_shoes]

I'm just updating my notes and noticed that some recipes printed in various books call for you mash out to 75-76oC while some do not. This has got me thinking but I can't seem to find much information on the science behind it.

What effect does this have compared to beers that are not mashed out with regards to efficiency and flavour profile?
Is there a rule of thumb for when to mash out?

 

[pittsy]

mashing out at 75c is for 2 reasons as far as i know , 1 is said to have a better run off when emptying and the other is to stop any further enzyme activity , once you raise the temp when mashing any previous activity like protein rest for example can no longer happen even if you lower temp etc , that's as much as i know about it .

 

[craigite]

mashing out at 75c is for 2 reasons as far as i know , 1 is said to have a better run off when emptying and the other is to stop any further enzyme activity , once you raise the temp when mashing any previous activity like protein rest for example can no longer happen even if you lower temp etc , that's as much as i know about it .

+1 :thumb:

Enzimes have a temperature at which they will permanently stop working, their denature temperature. Or something like that.

 

[kev]

How do you mash out? Do you dump in your sparge water?

K

 

[jonnymorris]

As I understand it, you can either add some sparge water during the last 10mins of your mash heated to about 90degC to raise the mash temp to 75degC or just sparge with 90degC water to raise the mash temp whilst sparging.

 

[boozy_shoes]

I always do it by putting the pot back on the hob or turning on the element underneath, but if your mash tun hasn't got a heat source then this wouldn't be possible unless you add some sparge water or run off some into a pan and heat on the hob before putting it back in the tun.

Thanks for the replies. Am I right in thinking then that all the mashing out does is make sparging easier by taking the temperature further away from the point at which the mash would "set" and stop the enzyme activity which might help hit a gravity more accurately but potentially lower the efficiency? Does anybody know if mashing out makes the wort less fermentable in the same way a higher intial mashing temperature does?

 

[pittsy]

After you have mashed in the sacc temps for around 45 mins all starch is converted to sugar , so efficiency is more down to getting those sugars out of mash tun rather than more converting needed . You can test this my doing a iodine test , it is quite surprising just how quick mashing is done (at sacc temps) . If it's a hassle to raise temp for mash out then don't , it ain't gonna make a difference just sparge as normal , p.s i would be more concerned about sparging with hot water above 80c (or it might be 85c) as this is getting into extracting tannins danger temp .

 

[jonnymorris]

p.s i would be more concerned about sparging with hot water above 80c...

Agreed but I was suggesting raising the temp of the mash to 75 rather than sparging at 90+. Clearly, once your mash temp is up you don't want to continue adding 90+ water.

 

[graysalchemy]

p.s i would be more concerned about sparging with hot water above 80c (or it might be 85c) as this is getting into extracting tannins danger temp .

It depends on what your mash temp is after the mash, with my overnight mashes typically my temps are 52-56c so I have started sparging at 90c to get a mash out temp of 75c (not that you need to denature the enzymes after 16hrs of mash they have done their job ) to assist the flow of the mash.

:thumb: :thumb:

 

[cwrw]

I often leave mashes for a standard 90 minutes (and is this too long?), top up and do a second batch sparge with near boiling water, as the temperature tends to drop rapidly - brings up the point of for how long and at what temperature is enzyme function lost/ harm done?

 

[graysalchemy]

You should raise your grain bed to 75c this usually means raising the sparge water to 85c. if you raise your grain bed into the 80's then you will extract tannins. :thumb:

 

[Good Ed]

as grays says :thumb: I try to get the grain bed between 72 & 76C; I fly sparge with a spinny sparge arm and for a 66C mash use a strike temperature of 90C and monitor the temperature of the grain bed when sparging

 

[Hirsty]

http://braukaiser.com/wiki/index.php?title=The_Science_of_Mashing

This website has some good info on the matter.