Overnight mashing with oven on to raise to mashout

[32Brew]

I've read several threads on the internets on overnight mashing where the mash temps lose some heat to some degree, and in the morning you carry on with the rest of the process. One area that I could not find any articles on is overnight mashing in the oven with it on the lowest setting so the mash will slowly rise in temp overnight.

During my regular process, I mash-in in a kettle and throw it in my preheated oven set to it's lowest temp at 170°F. (5gal batch size) I let the mash ride and the heat of the oven maintains the kettle temps. I've had "life" happen in the past and have gone as long as 2 hours with the mash going in the oven and have only had a degree or 2 increase in mash temps.

This leads to my set up and question. I could leave the mash in my oven and let it ride at 170 overnight. The mash would convert in the desired temp range in the first couple of hours and slowly mash out overnight to about 170. Would there be any negative affects on the mash if it sits at mashout temps for several hours before I get to it in the morning and sparge and boil? Is there something I'm not thinking of in this process?

 

[RM-MN]

The main idea of a mash out is that not all conversion is done and to preserve the profile of the sugars you quickly raise the temperature to 170 to stop conversion at that point. Then you slowly do your fly sparge to maximize the amount of sugars collected. You cannot raise the temperature quickly enough with your oven set at 170 so any conversion not completed will continue. You would be making a very long mash as the temperature rose slowly.

It shouldn't hurt nor help much except that your mash would be hotter so you can bring the wort to a boil quicker.

For nearly all situations, the mash out probably doesn't do what people expect it to and it is just done because they heard that someone else did it so it must be the right thing to do.

 

[balrog]

I suspect you'd end up with more fermentable wort, since the enzymes won't denature quickly without quick hot temp change so it'd be like you mashed lower, bringing with it changes in dryness, mouthfeel/body. Oh, I see RM-MN beat me. Again.

 

[soccerdad]

Palmer makes the point in How To Brew (Aspects of Lautering) that a mash out step is optional and often not necessary. He also makes the point that one way to perform the MO step is to add boiling water to get up to temp.

Presumably you could pull the kettle from the oven, stick a probe in, read something below 170, and add water at 200 or so degrees until you get to your desired 170.

Brew on

 

[32Brew]

Just like the others that mash overnight, I was looking to split up my brew day to work around family/kids etc. Would wort sitting at 170ish for multiple hours have any detriment?

 

[Sadu]

I have done a few overnight mashes before with good success. No mashout and despite the super long mash didn't find they finished too dry despite dropping several degrees overnight.

I can't see an issue with the OP's plan, so long as it doesn't get too hot and start extracting tannins from the grains.