Help with next AG batch: Mash out and Batch Sparging

I know that both of these subjects have been touched on quite a bit here, but I would like to revisit this subject so I am clear on how to approach my next batch.

I was reading through an older BYO article last night that discussed batch sparging. In the article they mashed using a 1.25 qts/lb ratio and at the end of the mash he added 180-185 F water (~5.5 qts) so he could obtain half the preboil volume (7 gal) from the mash and half from the sparge water (180-185F).

Ok, so I am clear on everything so far. However, in my case I would like to do a mash out because on my last two batches I ended with high attenuation. According to what I have read on HBT, the only way to control the attenuation is to either mash out or get the wort up to temp as fast as possible. Obviously, I am unable to do the latter because that didn't happen on the last two batches.

My next AG batch will contain 11.6 lbs of grain. If I mash at 1.25 qts/lb then I would end up with 3.6 gal in the mash tun. I assume I would loose 1.5 gal due to grain absorption and therefore be left with ~2.1 gal water. If my preboil is 7 gal and I want half from the mash and half from sparge then I would need to add 1.4 gal to the mash tun. However, if I want to do a mash out then I would need to add 2 gal at about 206 F to get the grain up to 170 F. That would give me 4.1 gal in the MT and leave me to sparge with 2.9 gal.

An alternative would be to mash in at 1 qt/lb instead of 1.25 qts/lb. At 1 qt/lb, I would need 3 gal for my strike water then loose 1.5 gal to the grain. In this case, I can do a mash out with 2 gal of water for a total of 3.5 gal in the mash tun. Therefore, allowing me to sparge with 3.5 gal for an even split between the two.

I hope all this makes sense. What is the best approach here?? Thanks in advance..

Controlling attenuation is much more coupled to the temperature during the initial 15-30 minutes of the mash than anything else. Yes, denaturing afterwards helps, but why not just raise your mash temp by 2 degrees.

My recommendation is to simply mash at a ratio that will naturally yield about 1/2 the preboil volume just on running off after vorlauf, then use a single batch sparge with 185F water and call it a day. The actual time it takes to do the sparge is about 15 minutes and it will be on the flame after that. In other words, it's not a concern like it is in fly sparging where the runoff may sit collecting for 45-60 minutes.

My first AG mashed at 152 and I still hit 80% attenuation and the second was mashed at 147 F and ended with 87% attenuation. I think it's taking me a long time to get the pot on the flame and up to temp because I am still learning the whole process.

I'm with Bobby on this- mash higher.

What yeast are you using? Maybe consider trying a different strain that attenuates less?

I guess it obvious but only change one thing at a time or you might not be able to tell why you are getting those results.

Both of them are belgian beers, so a higher mash temp wouldn't be appropriate for the style. If higher temp is what you are referring to. I know many Belgian brews have high attenuation, but I just want to be able to control the attenuation. In Brew Like a Monk, they say that low mash temps AND no mash out will allow the enzymes to continue working and therefore increase the fermentability...unless I misunderstood.. My understanding was that even with a higher mash temp, the enzyme continue to work until you get the temp up enough to halt their activity. Previously, on other HBT forums the consensus seemed to do a mash out...so..I am more unsure..

Lower mash temp yields more fermentable wort. Longer mash times can also lead to more fermentable wort. If fermentability is drifting more than you expect a mash out could help but its much easier and more productive to just mash higher.

also as said before try a less attenuative yeast

To me it sounds like your belgians are turning out nice and dry already like they should.

I get you. Sounds like you have a good handle on what the temps & changes in process will do for you. For those Belgians you cited before, well done! I'm always making an effort to make them dry enough. Did those batches have a significant amount of simple sugar? If so, that would play a factor in the attenuation you are experiencing.

I think the process you outlined to mash out would work fine. For me and my system, it would be easier to raise the mash temp or add some carapils than to mash out since I don't have a way to raise the mash temp easily. I like to keep the water to grain ratio consistent in an effort to hit my mash temps with repeatability.

Well, let's back up a second. How confident are you in your thermometer?

I would expect 87% attenuation with mashes in the 147F area for some yeasts. The only thing I'm suggesting is that the long-haul mash temp is much more influential than mashing out for that 15-20 additional minutes the wort may sit. But also, hot sparging will denature at least half of the wort almost immediately anyway. Mashing out with batch sparging is a bit of a pain because you're juggling two different pots with two different temp water at about the same time.

I have a thermometer installed in my MT and I check that with another thermometer. Both have agreed with one another. I will try increasing my mash ratio to maybe 1.5 qts-1.75 qts/lb, vorlauf, drain, then batch sparge with 185-190F water to get a total preboil volume of 7 gal. This should give me 50/50 split. Does this sound about right?