overnight mashing

[Brewberoza]

I have had heard a few brewers remark that they leave their mash overnight then sparge and boil the next day. I know brewers in former times had long mash time of 3 hours in some case but what advantage is there to leaving it overnight? Is it a brewing technique with a specific aim in mind or just a convenient way of living life around brewing? Also, how does one get temperature for sparge water, an insulated hlt or just heat it afresh in the morning?

And another question. What is acceptable temperature loss?

 

[RobWalker]

It speeds up your brewday, which imo is the main advantage. Youll also get drier beer, at least wiith biab - not sure if sparge will remedy that. While its good for saisons, dry stouts etc and will increase your efficiency, its not so good for sweeter beers.

 

[Brewberoza]

It speeds up your brewday, which imo is the main advantage. Youll also get drier beer, at least wiith biab - not sure if sparge will remedy that. While its good for saisons, dry stouts etc and will increase your efficiency, its not so good for sweeter beers.

Thanks

Why not so good for sweeter and does not so good mean bad or mean not an advantage to?

 

[RobWalker]

I'm not into the science so this is probably incorrect somewhat, but my understanding is that overnight mashing has more time to turn some of the tougher sugars into fermentable sugars. You can still produce plenty of dextrines in the first 1-2 hours, so it's entirely doable, just not advantageous like you say. I know aleman goes out of his way to get lower efficiency on the idea that it produces better bodied ale.

I've noticed beer is drier, but honestly, the efficiency increase and knocking a few hours off your brewday heavily outweighs a small matter of taste, unless you making a milk stout or whatever.

 

[Brewberoza]

How important is keeping temperature so the the enzymes are under control? Or am I missing the point. Blah, blah, blah, science his science that, but makes life easier.

Was thinking or reusing water left over from heat exchange to brew twice in a day. Just finish the job on day 2.

 

[RobWalker]

Mine's dropped to 40 overnight and the beer was still good!

 

[rpt]

I overnight mash for convenience. You want the temperature to stay above 50C as below that bacteria can get to work making off flavours. Although the boil will kill them it won't eliminate bad flavours.

 

[Brewberoza]

I overnight mash for convenience. You want the temperature to stay above 50C as below that bacteria can get to work making off flavours. Although the boil will kill them it won't eliminate bad flavours.

And do you agree better for dry styles?

 

[Jeltz]

Overnight mashes tend to give higher efficiency producing wort which is slightly more fermentable, hence the fermentation finishes a at little lower gravity giving a drier beer. The down side of that is that the beers can also end up tasting a little thinner than ideal.

When I did them the aim was convenience.

 

[dennisking]

The few times I have mashed overnight has resulted in a better efficiency but for some reason I've had a stuck mash each time.

 

[jonnymorris]

I've done about 10 over-night mashes and not had a stuck one yet. I do find getting the temp up for the mash out tricky and would prefer to do a plain 90min mash but it's just so convenient.

 

[rpt]

I haven't noticed any difference in the FG but I haven't done enough to say for sure especially as most of my brews are different recipes and OGs.

 

[Brewberoza]

I overnight mash for convenience. You want the temperature to stay above 50C as below that bacteria can get to work making off flavours. Although the boil will kill them it won't eliminate bad flavours.

So potential bacteria problem eh? What about using first wort hopping? They say it imparts no noticeable flavour to beer (maybe changes the PH slightly). Would the antiseptic properties of hops help here? Again I am thinking brewing once then recycling the warm Heat Exchange water so why not throw in some spent hops?

 

[jonnymorris]

If it's going to survive a 90min boil I don't think FWH are going to make much difference.

 

[Brewberoza]

If it's going to survive a 90min boil I don't think FWH are going to make much difference.

WAS thinking prevention rather than cure

Oh wait did I say First Wort Hopping? I meant mash hopping.