Is Sparging Obsolete?

[Black Island Brewer]

OK, 20 lbs of grain will absorb 2-1/2 gallon of water (1/8 gallon per pound). Water weighs 8.3 lb per gallon so that's 20.75 lb for a total of 40.75 lb. To get back to 20 lb, you'll need to remove 20.75 lbs of sugar from 20 lbs of grain.

Something's not adding up.

No, you need to remove a combination of 20.75 pounds of sugar AND water.

The assertion was made that you'll never be able to squeeze all the water out of the grain, which is true. But you also don't have to squeeze it all out in order to end up with the same weight in your bag than you started with.

The dry-basis course grind is a measure of how much non-starch (husk & protein) remains behind from a congress mash. So if a grain has an 80% DBCG, then one pound of grain would yield .2 pounds of remaining material once it was dried back to it's original moisture level.
Of course, we don't get that ideal, but we get close: 60, 70, 80, 90% depending on our mash/lauter efficiency. So assuming 75%, that pound of grain mashed, lautered and dried would be reduced to 0.4 pounds (0.8 pounds x .75 efficiency = .6 pounds extracted, 1.0-0.6=0.4 pounds) So in a 20 pound mash, at the end of lautering, we'd have 20.75 pounds of water and 8 pounds of husk/protein/unconverted starch. Squeeze one gallon of water out of the bag and you're pretty much back to your initial grain weight.

Of course, maybe I'm completely wrong.

 

[peterj]

No, you need to remove a combination of 20.75 pounds of sugar AND water.

The assertion was made that you'll never be able to squeeze all the water out of the grain, which is true. But you also don't have to squeeze it all out in order to end up with the same weight in your bag than you started with.

The dry-basis course grind is a measure of how much non-starch (husk & protein) remains behind from a congress mash. So if a grain has an 80% DBCG, then one pound of grain would yield .2 pounds of remaining material once it was dried back to it's original moisture level.
Of course, we don't get that ideal, but we get close: 60, 70, 80, 90% depending on our mash/lauter efficiency. So assuming 75%, that pound of grain mashed, lautered and dried would be reduced to 0.4 pounds (0.8 pounds x .75 efficiency = .6 pounds extracted, 1.0-0.6=0.4 pounds) So in a 20 pound mash, at the end of lautering, we'd have 20.75 pounds of water and 8 pounds of husk/protein/unconverted starch. Squeeze one gallon of water out of the bag and you're pretty much back to your initial grain weight.

Of course, maybe I'm completely wrong.

Well said.

The way I just calculated it was that in the same volume of water I can get about the same OG from 13 pounds of DME as 20 lbs of grain at 75% efficiency. So there must be 13 pounds of sugar that I can get out of the 20 lbs of grain. So after I rinse 13 pounds of sugar out that leaves 7 pounds of material behind. Which allows for 13 pounds of water to be absorbed. (13lbs)/(8.3lbs/gallon)=~1.5 gallons or 6 quarts. So that's an absorption of 0.3qts/lb which is just about exactly what I get when I do BIAB (I'm also a 2 method brewing abomination!)

 

[jbaysurfer]

This post is for Pricelessbrewing. Thanks for the math:

Seems like +/- 20% is a huge margin for error. But please double check since somewhere in this quote there is a mistake/typo.

The smallest grain absorption rate I've seen quoted under an extreme squeeze was 0.07 or so. I'm going to go with my calculators default of 0.8.

Is that .07 or .7? and what does that represent? .07G/lb of grain? In general it's about .125 per lb using the normal gravity drain method, which, I've found in my BIAB, given enough time is every bit as efficient as squeezing.

 

[wilserbrewer]

The above seems on par with my observations, my last batch I just let it hang high on the pulley above the kettle till about halfway through the boil, so maybe an hour in total draining...the bag of spent grain was surprisingly light. FWIW, I try to avoid the temptation to squeeze the bag, maybe for small batches, but for larger batches I find it easier and just as productive to let gravity drain the bag....jmo

To jbaysurfer, typical absorption is .07 - .08 gal / lb grain....I think priceless made a typo

 

[pricelessbrewing]

This post is for Pricelessbrewing. Thanks for the math:

Seems like +/- 20% is a huge margin for error. But please double check since somewhere in this quote there is a mistake/typo.


Is that .07 or .7? and what does that represent? .07G/lb of grain? In general it's about .125 per lb using the normal gravity drain method, which, I've found in my BIAB, given enough time is every bit as efficient as squeezing.

Sorry supposed to be 0.07 and 0.08 gallons/lb of grain. 0.125 is typical for a quick drain, and can get closer to a hard squeeze given enough time (probably within 0.02, or halfway between 0.125 and 0.08 or there abouts).

+/-20% is on the 7.5 lb, so it could be as low as 6Lb of corn sugar, or as high as 9. But if you really wanted to know, you could probably find gravity per pound for various malt sugars and compare it to corn sugar. I'm confident it's comparable.

 

[jbaysurfer]

Sorry supposed to be 0.07 and 0.08 gallons/lb of grain. 0.125 is typical for a quick drain, and can get closer to a hard squeeze given enough time (probably within 0.02, or halfway between 0.125 and 0.08 or there abouts).

+/-20% is on the 7.5 lb, so it could be as low as 6Lb of corn sugar, or as high as 9. But if you really wanted to know, you could probably find gravity per pound for various malt sugars and compare it to corn sugar. I'm confident it's comparable.

I guess I feel the same, it's likely comparable. Thanks for the clarification. I gotta say, that was pretty eye opening to me. Like Wilser though, I do let it drain for a good chunk of the boil and I do feel like I get pretty close to as much water as possible out of it, but maybe those squeezing their bags would surprise me by how much more water they extract. I personally don't want to touch that thing. It's 170F when I take it out of the kettle!

 

[pricelessbrewing]

I squeeze by pressing down on the bag with a pot lid. No hot surfaces for my hands that way.

 

[wilserbrewer]

It's 170F when I take it out of the kettle!

J

Just curious, why the mashout to 170?

I thought that myth was busted?


Wilserbrewer
Http://biabbags.webs.com/

 

[danz]

Haha- that reminds me!

I have a three vessel with a tippy dump. My false bottom is great (made by Jaybird), but even with a stand I'm getting grain going under it due to the MLT being an "upside down" version. As a result, I'm getting some issues with my bottom draining MLT and clogging. So, tomorrow, I also am doing a BIAB in a three vessel!

I have an inverted mash tun as well and had the same issue.To solved it I installed a cheap splatter screen from walmart which lays below my false bottom and the fine mesh catches anything that may make it through.

 

[jbaysurfer]

J

Just curious, why the mashout to 170?

I thought that myth was busted?


Wilserbrewer
Http://biabbags.webs.com/

Because I'm heating the kettle to 212 anyway, and I dunk sparge it...so I have that water at 180F or so.

I don't get too involved in the "myth" debates, but I have seen an increase in efficiency due to (what I hypothesize as) a less viscous wort solution, and easier sugar rinsing on my dunk sparge.

 

[Black Island Brewer]

because i'm heating the kettle to 212 anyway, and i dunk sparge it...so i have that water at 180f or so.

I don't get too involved in the "myth" debates, but i have seen an increase in efficiency due to (what i hypothesize as) a less viscous wort solution, and easier sugar rinsing on my dunk sparge.

+1

 

[TasunkaWitko]

I do BIAB with a bag that has four handles sewn to the top.

Stick a bar through the handles, put it in a large pail and twist the ball of grain until it tightens and the liquid drips out.

Tom

I was thinking of something very similar to this, albeit on a smaller scale as my batches are one gallon.

My wife's family is Slovak and they make what is called Easter cheese - part of the process involves squeezing the whey out in similar fashion. Reading your post brought the concept comparison straight into focus.

 

[Tegra]

"The one who says something is impossible should not interrupt the person doing it"

I do weigh before and after. The bag only weighs 2 oz. The math says it all.
(I am surprised that no one else seems to do this and they are in such disbelief)

I have seen some of the complicated presses that ones were using to squeeze the bag and I have been tempted to spend more time and more energy to get another few ounces but the effort/value has to be worth it. My process involves no more than a minute of work and I am at my equal weight.

Next time I will do an accurate water level measurement to see how much water is now in the bag. However, it has traded places with the sugar, so I guess there is more complicated math involved.

Tom

 

[jbaysurfer]

"The one who gets all preachy over the word impossible should read the disclaimer at the end of the post"

but maybe I'm missing something...

 

[passedpawn]

Juvenile bickering in here apparently isn't going to stop, so thread closed.