To mash out or NOT to mash out

I'd just like to hear from other experienced brewers. Do you mash out? Is it really necessary? Please give additional info to support your position. Thanks very much!!

For fly sparging it's pretty much a necessity IMO. For batch sparging it's totally optional, and IMO the water could be better used to increase sparge volume.

I get slightly better efficiency with a mash out. If I'm lazy I just start heating the runnings up the minute the kettle bottom is covered, which should help stop or slow enzyme activity.

I always mash out. I am a fly-sparger and it helps the mash run more smoothly.

I always mash out when fly sparging, and it increased my efficiency by 10% (from 75% to 85%)
I never mash out when batch sparging (which I only do if I am in a hurry). But I do heat the mash water hot enough to get the grain bed up into the upper 160's when batch sparging.

-a.

I batch sparge and don't do one unless I'm decocting a German lager. It dosen't increase my efficiency. It can if you don't have complete conversion.

I mash out. At the very least the temp increase helps thin out the sugars in the wort so it can flow easier.

I don't worry about it, and put the water into additional batch sparge volumes. Too much work for me. Kyle

I mash out as that wort has to be heated to boiling anyway. The BIAB grain becomes much more fluid, which I think makes the dunk sparge easier to extract remaining sugars.

I batch sparge. Tried with and without and didn't see the point of doing it. The first sparge addition is normally hot enough to raise the temp of the grain bed.

I don't see how it's possible to mashout properly with batch sparging in a cooler as many are doing. It's too much mass to heat up with just boiling water. You would have to fill the entire cooler with boiling water to get 3+gallons plus 10+lbs of grain plus cooler up to ~168*. This would leave you with no water to sparge with and/or require an extra long boil.

For batch sparging with a cooler, Yooper's method of doing the first sparge with extra hot water after draining first running seems much more practical and would achieve similar results. With this method, those first 3+gallons are drained so you only have to raise the temp of the grains and the cooler to ~168* which can be done with a reasonable amount of water.

I tried this method last week with a batch of pumpkin porter and even with 1st sparge at 190* water, I was only able get it up from 152* to just over 160*. I have to admit, this scared me a bit with worries of tannin extraction but Yooper said it works so it must be true. Krausen is just starting to settle down so we'll see how it turns out.

If you have a direct fired MLT, a traditional mash out is much more feasible. Just turn up the heat.

It's completely doable in my 10 gallon MLT for a 5 gallon beer, on average it's something like 2.5-3.5 gallons of added boiling water to hit 168+. Which leaves me with not a whole lot of sparge water. If you mashed tighter than the pseudo standard 1.25 qt/lb, you wouldn't need nearly as much.

If you're using a cooler MLT and want to do a mash out without sacrificing sparge volume, you can do it through decoction. If you're batch sparging in a cooler, I see absolutely no point in performing a mash out, but YMMV.

I brew via-BIAB and while I do not believe it is "necessary" to mash out, I do raise my temp to 168F before draining the bag. My feeling is that the extra heat will lower the viscosity of the wort and allow it to flow from the grains and out of the grain bag more easily. I don't know if it makes a difference scientifically, but it makes me feel better.

I prefer to not 'mash-out'. Mostly for safety reasons, because I do a slightly unusual lautering method method which requires me to transfer my kettle and pour the hot wort into my lautering tun. I would rather transfer and pour 150°F wort than 170°F wort. Sure, I would get slightly higher efficiency if I did the mash-out, but I'd prefer the safer and easier option.