Batch sparging a large beer

My normal mash efficiency is about 72% and the biggest beer I have done is about 1.070. I’m brewing a 1.090 beer for Extreme Beerfest and am wondering what I can expect for efficiency? I’m planning on mashing in at 1.1 instead of about 1.35 so that I have room to mash out…I figure mashing out will help extract some more sugar from the grains. When I batch sparge I stir the mash after the mashout addition and wait 10 minutes. Then, recirculate and drain the tun completely. Then, add sparge water equating to 1/2 my preboil volume, stir, and let it sit for another 10 minutes. Then, stiry again, recirculate and drain.

Any advice would be great.

Thanks!

Mark

You will probably take a 5% hit. Why don’t you brew a 1.070 beer and add some DME to the boil? That way you’ll have room to do a normal mash and sparge.

Yes, that came to mind. I do know it takes about 40 grams of DME to raise the OG one point for my setup. I thought about just draining and sparging twice to get all the sugars I could and then do an 90 or 120 minute boil.

DME is the way to go I think.

Thanks!

Mark

Why not just do a second batch sparge/third run off? You’ve already paid for the grain in the tun and dme isn’t cheap.

I could but I would have a bigger preboil volume and would need to probably double my boil time. I thought about doing a parti-gyle but did one a few weeks ago and is a pain in the butt with my current setup.

Mark

Do what I suggested and save the rest of the grain for another batch. Do it! :cheers:

This brings to mind that old BYO article about a hybrid continuous/batch sparge system that is supposed to be hyper efficient and supposedly supplanting continuous sparge systems in Germany.

In brief, it goes like this: You keep the grain bed submerged, but you keep supplying it with small batches of water proportionate to the volume running out of the tun.

Apparently, there was some sort of efficiency involved in this system. Although what it is, I can’t seem to remember. I’ll see if I can dig up that old article, it’s been bouncing around in the back of my mind lately.

http://www.homebrewtalk.com/f36/hybrid- ... ews-76516/

I remember reading fly sparging can cause channeling if using a bazooka screen type of lautering setup. But, others in my homebrew club have never run into that problem. I think hybrid sparging is definitely worth trying.

Mark

If you increase the pre-boil volume to compensate, your efficiency won’t drop.

If you’re getting 72% efficiency on a 1.070 beer, then your conversion efficiency is 90-95%, depending on pre-boil volume. Assuming that stays constant, then for a 1.090 beer at the same pre-boil volume you’d hit 64-67% efficiency.

Can you explain how you get 90-95 percent? How do you calculate conversion pct based on mash efficiency?

Thanks.

Mark

Reiterated mashing.

Mash half your grains as normal. Then use the wort to mash the 2nd half of the grains. Add additional water as needed to make up for grain absorption.

Probably not as well as Kai: http://braukaiser.com/wiki/index.php?ti … Efficiency

Kai’s Batch Sparge SImulator is a really easy way to calculate Conversion Efficiency, and to predict your OG (once you get a handle on your Conversion Efficiency) based on your grain weight and sparge volumes.

First, how do you quote a post?

I still do not understand how you can figure out CE based on the information I gave. 72% mash efficiency for 1.070 doesn’t seem like enough information. To calculate CE I need to divide measured mash OG by max potential. The 72% I gave is calculated by multiplying CE by lautering efficiency.

Slothrob, Kai’s simulator doesn’t calculate CE. You need to provide that.

Mark

^^^ This ^^^

Sparge twice, and boil 120 minutes, and your efficiency will be in the 70s. If you don’t, your efficiency will be 60 or less.

Dave, thanks.

Yes, that. :slight_smile: How do you do that? On other forums I use there’s a button called “quote post”.

Mark

There are different options to view the forum. In my view, there is a “Quote” button in the bottom right corner of every single post. Hit that, and it will allow you to quote and reply. If you don’t see this button, then you’ll need to configure your options (probably on User Control Panel or something like that).

EDIT: Yep, on Board preferences, set your “board style” to “subsilver2”.

Well, you can’t; that isn’t enough information. But the rest of the variables don’t have a huge impact. I assumed a 5.25 gal post-boil volume, and a weighted average potential extract of 36 point-gal/lb. So the grist weight would be: 5.2570/(36.72) = 14.2 lb. That sets the grain absorption at 1.7 gal, at which point calculating lauter efficiency for a double batch sparge is simple. For a 6.0 gal or 7.0 gal pre-boil volume, with equal runnings:

0.9*((3.0/4.7)+(3.0/4.7)(1.7/4.7)) = 0.78
0.9*((3.5/5.2)+(3.5/5.2)(1.7/5.2)) = 0.80

You can see that pre-boil volume doesn’t make much of a difference. The 0.9 is a fudge factor to account for the volume contributed by dissolved sugars. So the conversion efficiency is the overall mash efficiency divided by the lauter efficiency: 0.72/0.79 ~ 91%. Throwing in a little wiggle room for all the assumed values, you can still be almost certain the conversion efficiency was in the 85-95% range.

Kai’s spreadsheet would let you determine that, BTW. You just have to plug in all your numbers and then adjust the conversion efficiency until the OG lines up with what you got.

[quote=“dmtaylo2”]There are different options to view the forum. In my view, there is a “Quote” button in the bottom right corner of every single post. Hit that, and it will allow you to quote and reply. If you don’t see this button, then you’ll need to configure your options (probably on User Control Panel or something like that).

EDIT: Yep, on Board preferences, set your “board style” to “subsilver2”.[/quote]

Gravy! Thanks! You can take the rest of the day off. :slight_smile:

Mark

Well, you can’t; that isn’t enough information. But the rest of the variables don’t have a huge impact. I assumed a 5.25 gal post-boil volume, and a weighted average potential extract of 36 point-gal/lb. So the grist weight would be: 5.2570/(36.72) = 14.2 lb. That sets the grain absorption at 1.7 gal, at which point calculating lauter efficiency for a double batch sparge is simple. For a 6.0 gal or 7.0 gal pre-boil volume, with equal runnings:

0.9*((3.0/4.7)+(3.0/4.7)(1.7/4.7)) = 0.78
0.9*((3.5/5.2)+(3.5/5.2)(1.7/5.2)) = 0.80

You can see that pre-boil volume doesn’t make much of a difference. The 0.9 is a fudge factor to account for the volume contributed by dissolved sugars. So the conversion efficiency is the overall mash efficiency divided by the lauter efficiency: 0.72/0.79 ~ 91%. Throwing in a little wiggle room for all the assumed values, you can still be almost certain the conversion efficiency was in the 85-95% range.

Kai’s spreadsheet would let you determine that, BTW. You just have to plug in all your numbers and then adjust the conversion efficiency until the OG lines up with what you got.[/quote]

Thanks for this, I was missing how to calculate lautering efficiency. I also figured out how to maniupulate Kai’s batch sparge simulator by adjusting CE to figure out brewhouse efficiency.

Should I add deadspace to the above formula? Or, doesn’t it make a big difference in lautering efficiency? Also, it appears the simulator assumes you drain before adding any sparge water. What I do is add water to ensure the first drain is 1/2 my preboil amount. To simulate this should I add the top-off water to the mash water field?

Thanks again!

Mark