Mash out and denaturing of enzymes

[hoppyscotty]

So I tend to do a mash out at the end of the mash. Not entirely sure why, just something I learned about when I first started and seemed to be the normal thing to do on the instrucitonal videos I was watching. My understanding is that the purpose of a mash out is to denature the enzymes to stop any enzymatic conversions ahead of the sparge that can increase the viscosity of the mash and increase risk of stuck sparge...especially helpful if you've got lots of gummy grains in there like Oats or Rye. Probably a bit more to it that that, but idea is after your mash raise temp to 75 degrees C for ten mins or so.

My system is a RIMS system and I replaced my heating element with a lower wattage one recently. No issues maintaining normal mash temps, however seems to struggle getting the mash temp upto the elevated temp for mash out. The temp of the wort exiting the RIMS tube gets upto 75 degrees, but it seems to take ages for the body of the mash grist to come upto temp. Usually have about 14kg or so of grain in there.

However the hypothesis which I am after confirmation of, is that it is not necessary for the mash grist to get upto mashout temp...it should be sufficient for just the wort passing through the RIMS tube to get upto mashout temp and over ten minutes or so the entire volume of the wort should pass through the RIMS tube and get upto mashout temps and denature the enzymes???

What do you think?

 

[Agentgonzo]

I think that at the homebrew scale the mashout isn't necessary. It takes 10-20 minutes to sparge not-a-lot of additional conversion will happen over that time (your mash will have already converted starches to sugars).

Just people heat the kettle whilst sparging and so anything that's in the kettle will be denaturing the enzymes anyway.

A lot of pro breweries don't do a mash out. I saw very little difference/no difference between going from my 3 vessel setup with an insulated mash tun to a GF. I only do the mashout because it's zero effort and night theoretically help with wort viscosity/sparging

 

[Brewed_Force]

I think the key phrase is " just something I learned about when I first started and seemed to be the normal thing to do". I'm sure many of us when starting brewing just went with the prevailing ideas at the time, without questioning them.
There's many things in homebrew like that, probably having been borrowed from the brewing industry willy-nilly without any real thought about their effectiveness at the much smaller scales involved.
I know its not everyone's cup of tea, but the Brulosophy website has busted a lot of the myths surrounding the black arts of brewing.

 

[MashBag]

I dropped mash out years ago, as my unit takes 30 mins to get to boiling so seemed it was in the area long enough.

 

[AJA]

Main benefit of the mash out is to reduce the viscosity of the sugars to help them drain out. Hotter = thinner. Same benefit as using a hotter sparge.

 

[dmtaylor]

It is simply not necessary for most homebrewers. It only takes a few minutes to heat our batches up beyond 75C on the way up to the boil. Not hours like it might take for some commercial breweries. Waste of effort for most of us homebrewers to stop for a mashout rest before taking it the rest of the way up to the boil IMO.

 

[peebee]

I had to lay to rest this mashout idea after decades of thinking it was important. Some major breweries don't bother with it either.

I still let my mash heat up to 75C after mashing while I get on preparing the boil (so I still do a "mashout" ... gharg!).

 

[crescent city Mike]

Main benefit of the mash out is to reduce the viscosity of the sugars to help them drain out. Hotter = thinner. Same benefit as using a hotter sparge.

If you've mashed to produce a lot of dextrins, the mash-out would "set" the wort. Otherwise, as AJA notes, the mash-out simply thins the wort so that the sugars are more easily rinsed from the mash.

Some brewers don't have an apparent way to mash-out as they use a plastic ice chest as a mash tun. All they have to do is heat a portion of the sparge water to stir into the mash to raise the temp to 77 C degrees or so. There are calculators all over the web for that. These few extra minutes will improve your brewhouse efficiency. As I always say and can't stress enough, don't forget to acidify your sparge water down to 5.8 or 5.9 pH. That will alleviate astringency.