AG Mash Question

[mbbransc]

I've tried Google'g this but am coming up empty.

Are there any drawbacks to conducting the mash in advance? I'm thinking if I used extract to boil and make my wort, wouldn't it be sort of the same thing to do my mash in advance, let it cool, and then the next day bring it to a boil and continue brewing?

Any drawbacks, if it is possible?

thx

 

[JLem]

Since grain is covered in bacteria and wild yeast, letting the mash sit overnight you run the risk of having your wort go sour on you...I would say there is a high likelihood of this. Best bet would be to mash, lauter and sparge, and then at least bring the wort to a boil for 10 minutes to sterilize it. Cover it and then you can let it sit overnight.

 

[TANSTAAFB]

What would you be mashing in? I have heard of people doing overnight mashes in cooler MLTs with good results. The long mash would produce a highly fermentable wort so I would brew a style that calls for that like a Belgian or an IPA. You do have to make sure it doesn't turn into a sour mash though!

 

[brewkinger]

I have seen and posted in a couple of recent threads with regards to this matter. The risk of natural bacteria and infection is quite real. One recent thread included a picture of a wort that had been sitting less than 12 hours I think and it already had a thin oily film on the surface and very faint white web-like thready beginnings of a pellicle.

 

[mbbransc]

Hmm, sounds like a no-go. I thought since the wort would need to be boiled the next day anyway, it'd kill off any bacteria that developed.

thx all

 

[freisste]

Hmm, sounds like a no-go. I thought since the wort would need to be boiled the next day anyway, it'd kill off any bacteria that developed.

thx all

It will kill the bacteria, but the taste of the infection may remain.

 

[brewkinger]

It will kill the bacteria, but the taste of the infection may remain.

Which from my understanding of sour brews can be a positive thing. Could perhaps be an award winning beer if you let it.
Like Dirty Harry said "you feel lucky?"

 

[freisste]

Which from my understanding of sour brews can be a positive thing. Could perhaps be an award winning beer if you let it.
Like Dirty Harry said "you feel lucky?"

I'm not into sours, but for those who are this could be a good experiment.

I'm just wondering... The process for a sour is to make a beer, then when it is done fermenting you would add a different yeast or bacteria to ferment further. If you allowed it to get infected before boiling and pitching yeast, the bacteria would go through some of your initial sugar, possibly changing how your initial fermentation went (then your alcohol would boil of when you boiled hops). Not sure if all of his is an issue or not - again, I'm not into sours. Maybe this will be the new thing in sours....

 

[VonAle]

I've done a couple of overnight mash's, with success.

I doughed in at like 10 pm. 153 degrees. wrap the MT in blankets, etc.
Go to bed and get up at 4 am, heat the sparge water and resume.
My first runnings were about 130 degrees.

The beers turned out tasty, thin in body but not sour.
One was a saison and the other was a Belg IPA.

 

[woozy]

The story of a batch that had gone through a wild fermentation (without hops) in the 12 hours was enough to convince this doesn't work.

In theory, I think you can bring the runnings to boil and store them covered over-night but I don't know of anyone who has done this.

Hmm, sounds like a no-go. I thought since the wort would need to be boiled the next day anyway, it'd kill off any bacteria that developed.

thx all

Yeah... the point of killing the bacteria is to kill it before it does any damage. If you let it do damage for 12 hours, you can kill the bacteria but you can't undo the damage it's already done.

I suppose it's debatable just how much damage it can do in 12 hours. But the wild fermentation is pretty extreme.

 

[TANSTAAFB]

When conducting a sour mash you intentionally introduce lactic acid bacteria into your mash so it can give the wort a sour tang. You can control that process by pitching the bacteria from a culture directly into the mash or by adding acidulated malt after the main mash. Check out the latest Zymurgy article on Kentucky Common...you actually have to work pretty hard to get the mash to sour, it is more tart than sour in the finished product, and the boiling does kill the bacteria and stop the acid production which results in the tartness.

I think an overnight mash, especially conducted in a cooler which will hold temps and using a mash out to initially raise temps would be fine. There is not a lot of time for the bacteria to take hold and you could minimize that with a late night mash and an early morning boil. The biggest noticeable effect would be a beer with less body and perhaps a bit of tartness. In the correct style that would be perceived as an added dimension of complexity rather than a flaw. Hell, brew a Kentucky Common!