I am not too sure what to do about mashing out. I am supposed to raise the temperature of the mash. It seems the only way to do this is to use boiling water. Is this true? Do you circulate first, then add hot water. Does this mean that the mash tun has a lot of water? Or do you start draining while you add hot water? Why would you mash out with higher or lower temperatures, what does that achieve? Any comments would be great.
Paul
Are you batch sparging? If so, you really don’t need to do a mash. Mash out raises the temp of the grain to stop enzymatic activity that could continue over time while fly sparging. When batch sparging, run off takes so little time, there is not much concern with this. The only time I do a mash out is if I’m do a 12 gallon batch, and cannot heat all my strike water in my 7.5 gal kettle. And, when I have done a mash out, I typically heat the water to about 180* or so, and just mix it in. (carefully, remember HSA)
I add boiling water to mash out, and then recirculate. Yes, I have a lot of water in the tun – I usually add around a gallon to raise the temp for mashout. (Most decent brewing software will give you an exact calculation of the amount). When I start sparging, I Iet the level drop a bit before starting the flow of the sparge water.
If you have a direct fired mash tun and can recirculate that is all you need. You can also use a infusion or a decoction.
Add the boiling water, then vorlauf and drain. Or just skip the mashout. It has little no to benefit most of the time.
Try your beer without a mash out, At worst it will make your beer a little drier, if too dry raise your mash temp, if not dry enough drop your mash temp. If this fails (and it usually doesn’t) then try a mash out.
Fred
A mash out will thin your mash and help prevent stuck sparges. At least it does for me.
In addition to stopping enzymatic activity, a mash out supposedly makes the sugars thinner and allows them to flow more easily.
In addition to the other things mentioned, one option worth trying is to dough-in with less water. That makes for a thicker mash, and then when you add the water to bring the mash up to the mash out temp it isn’t quite so thin. There are trade-offs with each option, so it is good to try a few different variations and see which one produces the beer you like.
It doesn’t really matter about mash thickness by the time you get to mashout.
Not for conversion, but a thinner mash will run faster than a thick one.
Not according to experiments done by Kai Troester.
I don’t know anything about that, but I know that some boiling water right before vorlauf has always helped me achieve a fast runoff… In fact that’s the only reason I do it, because I never get it hot enough to denature.
And on the other side, my runoff speed doesn’t change whether I do a mashout or not. It’s a very fast runoff and it’s never stuck.
That’s because you don’t make wheat beers 
And damn proud of it! :) But I do use a fair amount of rye.
BURN!!!
I am fly sparging and have never done a batch sparge. How hot would the water be that you use for a batch sparge, same as the strike water? Do you get better efficiency for a batch sparge? I don’t know what HSA means either.
You should give batch sparging a try, at least one batch. If you batch sparge, no need to mash out. But, I do believe a msh out is done with boiling water.
Results vary from system to system, brewer to brewer, on batch vs. fly sparging. Use what works for you and don’t worry about it.
HSA is hot side aeration. It can be a problem in some breweries, but the guys at Basic Brewing Radio did some experiments that showed no difference unless you really whip the mash. YMMV.
I’ve not listened to any radio programs about HSA, but personally do not believe it is a problem pre-boil. Once my valve started sucking in air and aerated the runnings. For a 5 gallon batch (7 gallons of runnings) I had a completely full converted keg of foam pre-boil. The beer did not oxidize, nor stale prematurely. I cannot think of a better test pre-boil for HSA than that. Post boil I’m a believer in not splashing, but pre-boil, I’m not convinced it happens. YMMV