Batch Sparge Volume

[brown_dog_brews]

This should be an easy one and I'm just now having the "ah-ha" moment, I just need some solid experience to verify.

So, I have been batch sparging and making great beers but I kept having tons of sparge water left over after filling my kettle for boil...and THUS having terrible efficiency and lower ABV beers.

In fact today I yielded the ENTIRE volume of sparge water that I had added...PROMPTING me to think.. "Hey, maybe the grains are so saturated that they can't take any more" And I had been using my absorption rate on the sparge.

So here's the question: How do you account for sparge water in batch sparging? Am I correct that since the grains are saturated, you really don't need to factor an absorption rate?

 

[BansheeRider]

Good question. You account for grain absorption for your strike water. Then you measure how much wort you have from your first runnings and base your sparge water on how much more sweet wort you need for your pre boil. After a couple of trial and errors you should have it dialed in pretty well.

 

[TimelessCynic]

Banshee is right

For example i go for a total of a 27 liter boil.

I strike with 1.5 liters per lb of grain. So for 10 pounds i use 15 liters. My mash tun and grains always hold back around 6 liters so my first run off yields about 9 liters.

I rinse twice so each time i add 27-9 /2 liters of water.

 

[junior]

Banshee is right

For example i go for a total of a 27 liter boil.

I strike with 1.5 liters per lb of grain. So for 10 pounds i use 15 liters. My mash tun and grains always hold back around 6 liters so my first run off yields about 9 liters.

I rinse twice so each time i add 27-9 /2 liters of water.

Time,
Your grain is absorbing .6 liters per lb, I usually get .5 qt per lb, you should look in to improving your system.

 

[opiate82]

I too usually just guesstimate the amount of sparge water and usually have leftovers in the tun, although usually it is less than 1 gallon (and most times closer to 1-2 qts). I haven't had the low efficiency on lower ABV beers that you seem to have had however.

As others have pointed out, one thing you can do is take the time to calculate your system. It will make for a couple of longer brew days but once you figured out your grain-absorption rate and your mash tun dead space you should be able to dial it in pretty close each time. Software such as Beersmith will help you out.

As far as yielding your entire sparge volume, seems like you should get your entire sparge volume every time. You grain absorption and mash tun dead space should all be "filled up" with strike water.

 

[MattGuk]

I heard somewhere that grains will absorb their own weight in water pretty much, but it depends on what grains are being used, I would imagine highly roasted malts absorb less due to then grain being smaller.
If I use 13kg of 2-row then it usually does absorb 13Ltr of water. Measure your first runnings then add the volume that's left to fill your kettle as the grains will have absorbed as much as they can.

Cheers

 

[peterj]

So here's the question: How do you account for sparge water in batch sparging? Am I correct that since the grains are saturated, you really don't need to factor an absorption rate?

Yes. You should get out the same amount of sparge water that you put in. So just put in as much as you need to add to your first runnings to bring it to your pre-boil volume.

I usually use 0.5 qt per pound of grain for my absorption rate when calculating my mash water, then I add about 0.5-1 quart for dead space in my mash tun.

 

[TimelessCynic]

Time, Your grain is absorbing .6 liters per lb, I usually get .5 qt per lb, you should look in to improving your system.

My rectangular cooler mash tun has the drain higher than the bottom. Even if i tilt it i can't get all the wort out. I'll improve my setup when i buy a rig.

 

[peterj]

Time,
Your grain is absorbing .6 liters per lb, I usually get .5 qt per lb, you should look in to improving your system.

No, he's losing 6 liters to absorption and dead space in his mash tun. Grain absorption is pretty much constant on everyone's system, the only variable here would be deadspace. It sounds like he only has about 1 liter of deadspace which isn't too bad at all.

 

[junior]

No, he's losing 6 liters to absorption and dead space in his mash tun. Grain absorption is pretty much constant on everyone's system, the only variable here would be deadspace. It sounds like he only has about 1 liter of deadspace which isn't too bad at all.

Don't know what dead space is. It seems .5 qt per lb is what other people here are getting also.
Cheers

 

[opiate82]

Dead space is the little bit of water/wort left in the bottom of your mash tun because it doesn't drain every last drop.

 

[hophop]

Time, Your grain is absorbing .6 liters per lb, I usually get .5 qt per lb, you should look in to improving your system.

How would one go about improving their system for less grain absorption?

 

[junior]

How would one go about improving their system for less grain absorption?

Hop, what I did was go from stainless steel braid setup to copper manifold setup. With the manifold it took me various configurations to get were I am now. I am now getting between .42-.55 quarts per pound of grain. The .42 was done on 6-15-13, I am thinking maybe the humidity had something to do with it, but I don't know but seem logical. I was thinking of adding water to grain before mash, but don't think it is worth the extra step since my system is predicable.
Cheers

 

[brick]

To the OP: what efficiency are you actually getting? It sounds like yours is just lower than you would like to be, and you either need to adjust your process to bring it up (better crush? mashout infusion?) or just adjust your grain bill upward to match what your process actually delivers. I get the inclination to keep sparging...it's logical...but that's probably the hard way to get to where you want to be.

If batch sparging, I wouldn't mess with the manifold at all as long as it gets the job done.

 

[peterj]

Hop, what I did was go from stainless steel braid setup to copper manifold setup. With the manifold it took me various configurations to get were I am now. I am now getting between .42-.55 quarts per pound of grain. The .42 was done on 6-15-13, I am thinking maybe the humidity had something to do with it, but I don't know but seem logical. I was thinking of adding water to grain before mash, but don't think it is worth the extra step since my system is predicable.
Cheers

Changing your mash tun setup has no effect on grain absorption. The only things that would affect your grain absorption are the types of grain used (some grains absorb more water than others) and maybe humidity (though I don't think this would have a noticeable effect). By changing your mash tun setup you're just reducing the amount of dead space (which opiate82 correctly defined above) so you can drain more liquid out. So a better, more accurate, and more precise way to calculate your water needs would be to use a constant rate (like 0.5 qts/lb) for grain absorption and then figure out how much deadspace you have and add that to what you get for your qts/lb number. Your deadspace number will stay the same regardless of your grainbill.

 

[hophop]

That's what I thinking too Peter. That's why I asked how to improve or change grain absorption. I wasn't sure there was a way to reduce grain absorption.

 

[BrewCrewKevin]

Don't know what dead space is. It seems .5 qt per lb is what other people here are getting also.
Cheers

Just to clear it up for you, there are 2 different reasons water go into the mash tun and not come out.

1) Grain Absorption. Pretty standard at .5qt/lb. That's a property of grain, and has nothing to do with the system you're brewing on.
2) Dead Space. Anything below the valve you use to drain. That's dependent on your system (more specifically how high your valve is from the bottom of the mash tun.)

 

[brown_dog_brews]

To the OP: what efficiency are you actually getting? It sounds like yours is just lower than you would like to be, and you either need to adjust your process to bring it up (better crush? mashout infusion?) or just adjust your grain bill upward to match what your process actually delivers. I get the inclination to keep sparging...it's logical...but that's probably the hard way to get to where you want to be.

OP here...

Well, I have been getting in the upper 60's, usually around 68%; so pretty terrible. But, yes, I have been increasing my grain bills a little and also using any DME I might have on hand...particularly if after 30 min in the boil my SG isn't looking great.

HOWEVER, the beers I've been doing have turned out great. Maybe a little thinner but great...quite tasty and sessionable. Basically I was usually going for beers with an OG of 1.060ish and getting 1.050ish. Which sounds drastic but isn't as bad as you'd think especially if the process is still good, fermentation is well monitored and you have a group of buddies that are thirsty.

Sunday's brewday was supposed to be an "Imperial" IPA which turned out a little less imperial but still should yield a solid 7-7.5% ABV which is perfectly fine by me. And I kinda went into it thinking that way too...It's the "worst case scenairo, my efficiency is horrid but I have a good solid IPA; best case, I have a monster of an IPA that weighs in at 8-8.5%."

I do have ONE question about your reply..."how would a mashout infusion help efficiency?" I understand the crush suggestion and I have a great LHBS here in Nashville that is super committed to brewers and just bought a brand new mill. The crush is fantastic. But, I just don't see how a mashout increases efficiency points.

Is the thought process that a mashout with near boiling would release the upper end of the amalyse (sp) sugars? Also, wouldn't that release tannins? Let me know what you do...How much, what temp, how long?

Thanks a ton!
BDB

 

[fmr_army]

The idea behind a mashout is that higher temperature liquids generally can have more sugars in solution. Thus, you'll get more fermentables out. (Plus, you have the added benefit of stopping enzyme conversion, but that's not really relevant to this matter.)

Tannins shouldn't be an issue with batch sparging - I understand it's mainly a problem with fly sparging, since the pH increases (becomes less acidic) and thus temp control is more important. In any event, below 170 you should be fine - I personally batch sparge with slightly acidified, near-boiling water.

Put another way: if you mashed at 155, and raise to 170 before taking the first runnings, you'll have a higher OG on that first go 'round.

Another technique that I use to get all the sugary-goodness out is to over sparge (usually a third sparge/fourth running), and boil the shiznit out of the wort, often with a fan blowing across the kettle to hasten evaporation. 90 minute boils are becoming my norm for higher gravity beers, and I've taken 9.5 gallons down to 6 in that time.

 

[peterj]

Well, I have been getting in the upper 60's, usually around 68%; so pretty terrible. But, yes, I have been increasing my grain bills a little and also using any DME I might have on hand...particularly if after 30 min in the boil my SG isn't looking great.

HOWEVER, the beers I've been doing have turned out great. Maybe a little thinner but great...quite tasty and sessionable. Basically I was usually going for beers with an OG of 1.060ish and getting 1.050ish. Which sounds drastic but isn't as bad as you'd think especially if the process is still good, fermentation is well monitored and you have a group of buddies that are thirsty.

I wouldn't say 68% is terrible. It's not as high as some people, but I would say it's near or a little below average. But the actual number doesn't matter all that much as long as it's fairly consistent. If you are consistently getting lower OGs you should just adjust your recipes (by adding more grain) to what your efficiency is and you will be able to hit your OGs right on.

Another technique that I use to get all the sugary-goodness out is to over sparge (usually a third sparge/fourth running), and boil the shiznit out of the wort, often with a fan blowing across the kettle to hasten evaporation. 90 minute boils are becoming my norm for higher gravity beers, and I've taken 9.5 gallons down to 6 in that time.

That's a pretty good idea! It would take some dialing in to see what my evaporation rates are, but I might have to try that on my next high gravity brew. Do you set the fan up on a table or something so it doesn't interfere with the burner flame? Or maybe you have a wind shield?

 

[fmr_army]

I have a stand-fan that has a pretty narrow, powerful stream of air. It is the right height to go across the top of the kettle. A side benefit is that I can crank the heat and not worry about boil over.

I would reckon that a fan on a table would work well also - but you're right that it could interfere with the flame if you're not careful.

 

[junior]

Changing your mash tun setup has no effect on grain absorption. The only things that would affect your grain absorption are the types of grain used (some grains absorb more water than others) and maybe humidity (though I don't think this would have a noticeable effect). By changing your mash tun setup you're just reducing the amount of dead space (which opiate82 correctly defined above) so you can drain more liquid out. So a better, more accurate, and more precise way to calculate your water needs would be to use a constant rate (like 0.5 qts/lb) for grain absorption and then figure out how much deadspace you have and add that to what you get for your qts/lb number. Your deadspace number will stay the same regardless of your grainbill.

Peter, I should have specified I was talking about head space and not absorption of water. I still say there has got to be a way to improve water absorption, maybe adding water before mash, even if there was a way it is not worth the extra step for me.