Maximizing Efficiency when Batch Sparging

matalec1984 said:

First off thank you for the information, this makes me feel much better about my efficiency on this latest batch. my hydrometer is calibrated to 68, and the wort was around 140 my pre-boil reading was about 1.038 Temp corrected is 1.053 and my expect was 1.057.

My question now moves to my actual OG. I finished with 5 gal of wort into my primary. Took my initial Grav reading and got 1.052 temp corrected to 1.054 which is much lower then my expected OG. I feel like something must be wrong here. Any thoughts?

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My first thought is that the initial reading is off. Any temperature adjustment above 100* will be inaccurate IMHO. You need to cool down the sample first before taking a reading. Pour it in to a glass and keep it around until the end if you want to check back after it is at 68. What was your expected starting gravity and expected efficiency?

Thanks again for everyone's advice. After thinking about it for a few it came to me as well that I should let the wort cool and then take a preboil grav reading later on once it has cooled. Furthermore since I was a little tipsy when doing this the other day I forgot to temp correct my OG as well. I generally haven't worried about efficiency in the pst and always remember to temp correct my OG but somehow I didn't the other day.

My temp correct pre-boil was 1.054 which may be inaccurate do to the temp it was taken at. The expected was 1.057

My OG temp corrected was 1.057 expected was 1.061

Not as bad as I originally thought.

Just starting to get the idea of all-grain brewing. But question, why do we not soak the sparge water at all? We soak strike water for 60 minutes to give it time to collect the sugars, etc..... but wouldn't allowing the sparge water to soak for 20-30 minutes be similarly beneficial?

it's because during the mash, enzymes are converting starches to sugars. In the sparge, all we're doing is aiding in collecting enough sugar to hit our target OG, not converting anymore.

The mash is much, much more than just a soak.

But what harm would come from allowing the sparge water to soak for even 15 minutes? If any starches have not fully converted to sugars, this may give that last 5% of them the opportunity to do so. Additionally, holding the sparge water in place for at least a few minutes might help ensure it has a chance to touch every bit of the grain, rather than begin to channel or miss one particular spot. It just seems like only good things could come from giving the sparge water some time.

This way of thinking is what's also causing me to not understand how fly sparging could in any way increase efficiency.

I leave the sparge water in for 15 minutes. Some thoughts about that:

• At the higher temp the sparge water will be, the enzymes will be denatured anyway (or well on their way to that), so it doesn't seem to me there is a heck of a lot of conversion happening.
• I like the soaking precisely because of what you said: better rinsing and hopefully yield. But also, at the higher temperature, I believe the viscosity of the liquid goes down, so there is less risk (minimal as it may be to begin with) of a stuck sparge.
• Because it's a one-time thing (unless you do multiple spargings for the same batch), I don't think pH is affected (in a downward manner) the way it is with fly sparging.

I'm fairly sure this information is solid, but welcome feedback on it.

If conversion is not 100% at the time you introduce a batch sparge, the elevated temps will give it that last push. Enzymes do not denature instantly and higher temps do make them act faster just before they are choked out (not really, they're just chemicals).

If conversion WAS complete, the longer soak would only increase efficiency if your crush was abnormally coarse such that diffusion of sugar from a large bit of endosperm was buffered in some way. Fix your crush, adjust your mill, etc.

Firebirddude, there is no concept of channeling in batch sparging. All the wort in the tun after you stir the sparge addition in, is exactly the same concentration of sugar. Regarding your post above, the 60 minute rest is to allow conversion of starch to sugar, not to "collect" the sugar.

There is no harm in allowing the sparge to sit, but at worst it would be a waste of time. All grain brew days are long enough as it is.

I guess that the big question that have to be answered in what is the maximum theoretical sugar that one can extract from a grain. If this amount varies from grain to grain, then it will be very complex to calculate efficiency.

I am under the impression that 40 is reference number obtained from the maximum solubility of table sugar (sucrose). Since there is a mixture of sugars in the mash and with different solubilities, it may be difficult to establish a reference "true" density value.

Once this is resolved, the optimization can be performed via a factorial experimental design, with (say) sparging volume and mill setting as factors. The measured responses may be wort density and %efficiency.

In order to get an accurate reading, I would use a two-three decimal scale and a 10-ml graduated cylinder.

Thanks, Nil

Maybe I already posted this somewhere in this thread, but over the course of 14 years and 415 batches that have been batch sparged, I've tried a lot of different "wait times" after adding the sparge water. From 30 min. down to zero min., there has been no change whatsoever in efficiency or fermentability. You can theorize all you like, but there's the hard experimental data. Try it for yourself.

Fair enough. Just asking.

Thanks guys.

I am kinda new at the brewing, I started out from ground zero. Each batch I change one component and they are getting much better. One thing I do that might be relevant to the conversation is place hole grain around my drainage system and I flip it upside down so the finer particles don't clog it. This has been working pretty well. I have a grinder that I reconditioned from an old wall hanger. In short, I can set it very fine and course but the in between will vary a bunch. It seems to work out good because on my last batch of mash out I was about 1.042 sg. The down fall came when I sparged it and brought it way down. I had to add some corn sugar in the boil to increase the sg. I am thinking next time of not sparging and just using more grain along with more water in the wort. Any thoughts?

firebirdude said:

But what harm would come from allowing the sparge water to soak for even 15 minutes? If any starches have not fully converted to sugars, this may give that last 5% of them the opportunity to do so. Additionally, holding the sparge water in place for at least a few minutes might help ensure it has a chance to touch every bit of the grain, rather than begin to channel or miss one particular spot. It just seems like only good things could come from giving the sparge water some time.

This way of thinking is what's also causing me to not understand how fly sparging could in any way increase efficiency.

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I think what you are mentioning here is largely responsible for the bumps in efficiency that people sometimes see when doing a batch sparge rest, a mash out, or carefully controlling sparge temps. If conversion hasn't completed, the temperature can provide a bump. But, as I see it, that's just dodging the problem. If your starch conversion hasn't finished, you shouldn't be ending your mash in the first place.

The reason that fly sparging is more efficient (so long as everything works right) is that you are constantly draining highly concentrated wort and replacing it with fresh water. The sugars that you leave behind are left behind in the water absorbed by your grainbed. When you batch sparge, you are diluting and then re-draining that sugar. Likewise, the kinds of proportions you use will impact the quantities of sugars that get left behind.

For example, one 12 quart batch sparge is less efficient than two 6 quart batches, which is in turn less efficient than three 4 quart or four 3 quart batch sparges. When done properly, fly sparging is the limit case: it's like doing an incredibly large number of incredibly small batch sparges. You pull out more concentrated wort earlier, and thus leave less concentrated wort behind in the tun.

Whether it's worth the effort, of course, is a completely different question.

Ehhh to be honest, it really sounds like a rumor that someone thinking way too far into it dreamed up. I really don't see any numbers behind it and it would appear people who have done hundreds of brews using both methods agree.

"Yeah man. It's like "highly concentrated" wort comes out the bottom while you replace it with clean water up top. It, like, makes all your water into highly concentrated wort."

If we really want to think like that.... then you would have to admit that the sparge water you're ladling in mixes with the strike water at least somewhat. It doesn't just stay on the surface in a solid level or something. So then it's entirely possible that those early ladles of sparge water may make it out of your mash tun before every molecule of your strike water. This could only be translated into a loss in efficiency.

Again, I really don't think it matters much. Just pointing out the depth that one could assume. But in actuality, it makes a negligible difference.

firebirdude said:

Ehhh to be honest, it really sounds like a rumor that someone thinking way too far into it dreamed up. I really don't see any numbers behind it and it would appear people who have done hundreds of brews using both methods agree.

"Yeah man. It's like "highly concentrated" wort comes out the bottom while you replace it with clean water up top. It, like, makes all your water into highly concentrated wort."

If we really want to think like that.... then you would have to admit that the sparge water you're ladling in mixes with the strike water at least somewhat. It doesn't just stay on the surface in a solid level or something. So then it's entirely possible that those early ladles of sparge water may make it out of your mash tun before every molecule of your strike water. This could only be translated into a loss in efficiency.

Again, I really don't think it matters much. Just pointing out the depth that one could assume. But in actuality, it makes a negligible difference.

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Actually, liquid stratification in these kinds of sedimentary environments is quite well understood. I own a business that sells and exports coffee, and I've seen dozens if not hundreds of experimental articles talking about exactly this phenomena in the context of coffee extraction. I'd also refer you to chapter six of Brewing Science and Practice by Briggs, or this article by Kaiser that's been linked here before, both of which describe actual experiments on exactly this front. Of course, then, like, you'd have to read a book and stuff, man.

I'm not trying to talk you into fly sparging. I used to do it, but have done a single batch sparge for a long time now. But, all this is quite easy to test, as several of us on this forum have done. If you feel so inclined, build yourself a fly sparge setup and take readings at various depths of the grain bed. The differences in the numbers are not huge, and certainly they are small enough that I don't bother with it any more. But, to call fly sparging a "rumor" is a bit rash, eh?

The reason a properly performed fly sparge provides maximum efficiency is the same reason why CFC and plate chillers are the most efficient chillers. It's all about maintaining the max delta. Of course, in chiller's it's temp delta and in sparging it's sugar concentration.

This really isn't wishful thinking.

MalFet said:

For example, one 12 quart batch sparge is less efficient than two 6 quart batches, which is in turn less efficient than three 4 quart or four 3 quart batch sparges. When done properly, fly sparging is the limit case: it's like doing an incredibly large number of incredibly small batch sparges. You pull out more concentrated wort earlier, and thus leave less concentrated wort behind in the tun.

Whether it's worth the effort, of course, is a completely different question.

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That's the theory, but the reality for me is that when I do multiple I see so little increase in efficiency that it could be attributed to measurement error.

Denny said:

That's the theory, but the reality for me is that when I do multiple I see so little increase in efficiency that it could be attributed to measurement error.

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Sure. You've mentioned seeing a 1-2% difference. I saw a 3-4% difference when I ran the comparisons. Those are close numbers in any case, and the difference in our differences is easily attributable to proportions, method, etc.

The most carefully designed study I've seen on this is Kaiser's. The fact that his numbers confirm to what I've seen and conform to the "theory" of it all makes me think they're reliable.

But, for the record, I single batch sparge...using a system that I learned from you no less. I'm not trying to talk anyone into any system, and personally I've decided the slight differences aren't worth the extra effort. My only point here was to explain the mechanics of it all.

I've been hitting low 80%s on my last couple brews batch sparging.

2 hour mash with a single 175 degree sparge seems to be working well for me.

Just started down this path of batch sparging and I could not be happier with the results. All the batches have turned out between 83-86% efficiency.

Trying my first all grain in 2 weeks, this has been a great help. Thanks!

What is the preferred method of batch sparging then? Are you putting all the volume of water in at once? 50/50? 1/3 then 2/3? Are you bringing up the wort to a mashout of 170? Are you even doing a mashout?

It would be nice to have some of the sticky discussions blanked out and then the latest info put as the baseline again unless something new has been discovered.

Of course BIABers would say you don't need to sparge - which is funny because it goes against everything that Palmer and Pap have said about water pH and such as well as keeping the water to grain ratio low.

I just want a simple yet relative efficient way of getting that sugar out. If a batch sparge with 1/3 total volume upfront and 2/3 remainder gets me in the upper 70s-low 80s - I'll be content with that method. I don't want to go down the fly sparge or sparging 4-5 times for a couple of percent but at the same token I don't want to BIAB at 60-70% either...can't do it anyhow because I only have a 8 gal kettle. Can someone paraphase batch parging for me?

Kuhndog said:

What is the preferred method of batch sparging then? Are you putting all the volume of water in at once? 50/50? 1/3 then 2/3? Are you bringing up the wort to a mashout of 170? Are you even doing a mashout?

It would be nice to have some of the sticky discussions blanked out and then the latest info put as the baseline again unless something new has been discovered.

Of course BIABers would say you don't need to sparge - which is funny because it goes against everything that Palmer and Pap have said about water pH and such as well as keeping the water to grain ratio low.

I just want a simple yet relative efficient way of getting that sugar out. If a batch sparge with 1/3 total volume upfront and 2/3 remainder gets me in the upper 70s-low 80s - I'll be content with that method. I don't want to go down the fly sparge or sparging 4-5 times for a couple of percent but at the same token I don't want to BIAB at 60-70% either...can't do it anyhow because I only have a 8 gal kettle. Can someone paraphase batch parging for me?

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Mash with whatever ratio you like. I use 1.6-1.75 qt./lb. Mashout not necessary. After you runoff the mash, measure how much you have and subtract that from your total boil volume. The answer you get is how much sparge water to use. Heat that amount to about 190F and stir it in. Vorlauf and runoff like you did for the mash. Bingo, you;re done. I average 85% efficiency with that method.

See www.dennybrew.com for more detailed info if you want to.

Denny said:

Mash with whatever ratio you like.

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I agree. I tend to mash with whatever ratio gets me an easy to measure volume of water (3 gallons for example, compared to a set ratio that may wind up with 2.68 gallons needed).

There are too many variables at the homebrewer scale that are difficult to measure with complete reliability, so I find whole volumes of water eaiset to deal with for me.

Totally agree with both of the above. There are so many other variables that are far more important. I'm not gonna waste time measuring out fractions of quarts on brew day - it just doesn't make enough difference.

I do measure my runoff/collection volumes precisely though - that is worth getting right.

TyTanium said:

I do measure my runoff/collection volumes precisely though - that is worth getting right.

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Adjusting for expansion/contraction based on temperature, right?

AZ_IPA said:

Adjusting for expansion/contraction based on temperature, right?

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Absolutely...using Kaiser's brewsheets. Good clarification.

Kuhn,

I can't stand when people overcomplicate things. After reading a ton on batch sparging and after tweaking my method a little at a time using a lot of info posted from Denny(thanks!) I've come to a very simple, easy and efficient technique that I get a pretty constant 80-82% effeciency from and more importantly delicious beer.

Hope this helps.

Figure out for your system what your preboil volume needs to be. For me its 7 gallons. Now for every batch you do just figure out what amount of strike water gets you half your pre boil volume...(1.4-1.6 qt per pound of grain...whatever it is). Mix your strike water really really well so the tempurature is consistant throughout and no dough balls. After the mash drain your tun, and add the other half of your preboil volume(3.5 gallons for me). I add my sparge water at about 195-200 and it brings my grain bed to around 170. Stir the crap out of the it and then vorloff and drain as quickly as it will drain. I too found that double batch sparging does very very little for me. Its way faster to just do a single sparge and I'd gladly give up 1-2% effeciency to save time. One important thing ive found too is make sure you get every drop of wort you can...definitely don't leave any behind because maybe you are going to overshoot your pre boil volume. Grain crush was the other big help to get me where I wanted to be. I have a pretty fine crush which seemed to help quite a bit.

It really is as simple as that. A lot of people I think try to overcomplicate it. I found experimenting myself and drawing testing the theories talked about here was the most helpful thing. Test it for yourself don't let 100 different peoples opinions influence you. You don't even know if they make good beer .

Wow took me so long to respond ya got quite a few responses haha. Guess that's what I get for having big thumbs and trying to type on my touch screen phone.

After 15 pages of reading and checking out links to other resources...I have come up with a question. Several sources say to drain the mash and sparge as quickly as possible after the grain bed has set.

What happens if you drain it slowly? I ask because I just made a batch yesterday and slowed down the draining (unlike my previous batches). I'm not sure if I have a combination of problems (e.g. grain crush, less boil off, etc), but my OG was WAY!!!! low. It ended being 1.072 when it should have been around 1.086.

I'm sure the beer will turn out fine, but I'm wondering where or what went wrong. I do think the grain could have been crushed slightly finer, but it is a learning process for me

Well if you're batch sparging you just wasted time. That's the really.nice thing about batch sparging, its really fast. You draining slowly definitely didn't cause you're og problem. You'd have to explain your process and whether or not you crushed your own grains etc.

thirstyutahn said:

Well if you're batch sparging you just wasted time. That's the really.nice thing about batch sparging, its really fast. You draining slowly definitely didn't cause you're og problem. You'd have to explain your process and whether or not you crushed your own grains etc.

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Thanks for the quick reply. I did crush my own grain at my LHBS. I have crushed all my grain there for previous batches, but he has been having mill issues lately, so I think the spacing may have changed (I noticed that there was not as much grain dust as in the past).

Here is what I did...

Mash (10gal Igloo MLT)
260oz grain
1. Pre-heated the MLT, then added 5gal @ 167F to the grain; stirred well (no dough balls)
2. 30 min into the mash, stirred again, checked temp - 158F
3. 60 min end of mash, stirred, checked temp - 158F (I didn't lose as much heat as I have in the past, so it was a higher than my target of 152F)
4. Drained mash till empty over period of ~20min
5. Added my sparge water - 3.6gal @ 170F (prob should have been hotter to bring the grain bed back up to temp)
6. Stirred and let sit for 5 min (again, prob should have been longer)
7. Drained mash till empty over period of ~10 min
8. Ended up with a little more wort than my recipe said I would (~.3gal more)

I partially cover my boils so I don't lose as much to evaporation, but my ending post boil was on target.

The remaining portions of the recipe went as planned. I did not test the mash out gravity. I only tested after the boil as usual. I'm just shocked that I was significantly off...not just a few points.

I know that without seeing my process, equipment, grain crush size, etc.; identifying the source of my problem is difficult. Though, any advice that could help me to not reproduce this problem would be appreciated.

Thanks.

Process seems fine. Post your recipe?

TyTanium said:

Process seems fine. Post your recipe?

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http://www.itrider.net/downloads/PlinyElderClone.pdf

Seems like a crush issue. Though people often see a drop in efficiency with larger grainbills. Also, did you add the sugar?

It really helps to take gravity & volume measurements throughout so you can diagnose where your problems are.

TyTanium said:

Seems like a crush issue. Though people often see a drop in efficiency with larger grainbills. Also, did you add the sugar?

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Really...a drop with more grain. Hmmm, I wonder how to correct for this. Yes, I added the sugar to the boil at the very beginning.

TyTanium said:

It really helps to take gravity & volume measurements throughout so you can diagnose where your problems are.

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Going forward I plan to purchase a refractometer (I borrowed a friends for this brew) so I can test throughout. That would definitely help narrow down any problems.

itrider said:

Really...a drop with more grain. Hmmm, I wonder how to correct for this.

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You can sparge more to rinse the rest of the sugars out. That also means you need to boil longer to hit your OG.

Denny said:

You can sparge more to rinse the rest of the sugars out. That also means you need to boil longer to hit your OG.

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Thanks for the tip. Now I would just need to find a larger pot I have been filing my current one up to the max! hahaha

itrider said:

Thanks for the tip. Now I would just need to find a larger pot I have been filing my current one up to the max! hahaha

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Always seems to work that way, doesn't it?

I'm so glad I found this thread! I've been BIAB for a while and recently picked up a cooler mash tun.My first batch ( last Fri ) was Edworts pale ale.My O.G was off by 10...ouch I was always pretty much there when BIAB. I'll tweak somethings using this thread.

Thanks Again

Tizzomes said:

I'm so glad I found this thread! I've been BIAB for a while and recently picked up a cooler mash tun.My first batch ( last Fri ) was Edworts pale ale.My O.G was off by 10...ouch I was always pretty much there when BIAB. I'll tweak somethings using this thread.

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This is my story as well. I done a bunch of BIAB and had it dialed in pretty well around 72-75%
Today I did my first mash in a cooler following the steps outlined here and ended up around 54.8%. I have my own mill and have been doing well with the crush that I have it at. Today's recipe was 60% wheat malt. Do I have to crush finer with wheat? I know the kernels are a little smaller.