Math for mash and sparge does not add up, help!

In the stickies I've read here, it seems that for every pound of grain, I am adding 1-1.25 quarts of water. Got it. Then, I am sparging with 1/2 gallon of water per pound of grain, Got it.

Why then, does every recipe I find - not follow that rule at all - or am I misunderstanding?

I downloaded a nut-brown ale. Batch size 6 gal. Boil volume 8.5 gal. Fermentables, 13 pounds.

If I follow the sticky for new a/g brewers....I should be mashing in with about 4 gallons of water at 152 degrees and then sparging in two phases with an additional 6.5 gallons of 200 degree water.

I lose about 50% to mash loss due to the 13 pounds of grains soaking it up and the rest below my ball valve. So if I am gleaning about 2-3 gallons of mash, I am then sparging with almost 7 gallons of hot water? For a boil volume of about 10 gallons? Huh?

According to the recipe, I am boiling in 6 gallons of water, sparging enough to bring it up to 8.5 gallons to boil with, losing about 1.5 gallons to boil off, and fermenting about 6 gallons at the end. Right?

Have I confused you as much as I am confused?

First off... 200 degree water is way too hot for sparge. Sparge at 170. All you need to do is rinse the grains and stop the conversion process. 170 water will be fine for that and wont extract tannins.

Also, I think your calcs are a little off. I think 1/2gal per lb is too much water.

For 13 lbs of grain your total water should be somewhere (according to my calcs) around 8.8gals.

4.3 gals mash (1.33qt/lb)
4.5 gals sparge

Resulting in about 6.5 gals pre-boil.

Check out This Website. The water calculator works really well, I use it every batch and pretty much nail my numbers


One thing you can always do is run your mash, heat up more sparge water than is needed and add as much to the grains as you need to hit your pre-boil numbers, keeping in mind you should get pretty close to 100% of the sparge water into the boil kettle (no grain absorption at this point)

Thank you! - I appreciate the help.

dmaddox said:

In the stickies I've read here, it seems that for every pound of grain, I am adding 1-1.25 quarts of water. Got it. Then, I am sparging with 1/2 gallon of water per pound of grain, Got it.

Why then, does every recipe I find - not follow that rule at all - or am I misunderstanding?

I downloaded a nut-brown ale. Batch size 6 gal. Boil volume 8.5 gal. Fermentables, 13 pounds.

If I follow the sticky for new a/g brewers....I should be mashing in with about 4 gallons of water at 152 degrees and then sparging in two phases with an additional 6.5 gallons of 200 degree water.

I lose about 50% to mash loss due to the 13 pounds of grains soaking it up and the rest below my ball valve. So if I am gleaning about 2-3 gallons of mash, I am then sparging with almost 7 gallons of hot water? For a boil volume of about 10 gallons? Huh?

According to the recipe, I am boiling in 6 gallons of water, sparging enough to bring it up to 8.5 gallons to boil with, losing about 1.5 gallons to boil off, and fermenting about 6 gallons at the end. Right?

Have I confused you as much as I am confused?

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The way it should read is "I am adding 1.25-2 quarts of water per pound of grain. Then, I am sparging with UP TO 1/2 gallon of water per pound of grain, or until the boil volume is reached.

It's true that for maximum efficiency, you could sparge more and boil down more, but most people don't want to spend three hours and the cost of fuel to do that.

Sparge up to your boil volume, but no more than 1/2 gallon of water per pound of grain.

To figure out a good estimate of water needed, consider that grain will absorb about .125 gallons of liquid per pound of grain. So, say you have 10 pounds of grain. Mash in with 15 quarts of water (3.75 grallons). The grain will absorb 1.25 gallons of liquid, so you'd get about 2.5 gallons of first runnings. If your boil volume needs to be 6.5 gallons (as an example), you'd sparge with 4 gallons of water.

Calculators help, but if you remember the basic premise there it is a good double check of the volumes you need. For my system, I boil off 1.5 gallons an hour, but yours may be more or less.

I've never heard of this 1/2 gallon per pound sparge rule before. Wherever it comes from, it's flat out wrong.

You'll want to find or develop your own mash volume calculator. I have my own spreadsheet. Based on it, I calculate:

Mash in 4 gallons at an initial 171 F which should fall to the 152 F desired.

Sparge with 5-5.5 gallons at 188 F which will mix with the 152 F to give the 168 F desired for mashout.

So the total volume of water you need for this batch is about 9.5 gallons. I figure 0.1 gallons per pound is soaked up permanently in the grains, about 1 quart is lost below the valve, 1.5 gallons is boiled off, 0.5 quart is lost in cold break and hop particulate, 1 quart is lost due to contraction after the hot wort cools, 1.5 quarts is lost to trub from yeast, hops, proteins, etc. This will leave you with about 5.6 gallons after all is said and done at bottling/kegging time.

The numbers I quoted should be decent ballpark figures for most batches, but you'll want to customize based on your own process and experience. Then you too can easily calculate your water volumes in the future.

Cheers.

dmtaylor said:

Sparge with 5-5.5 gallons at 188 F which will mix with the 152 F to give the 168 F desired for mashout.

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Just want to avoid confusion (and maybe save you some time), but what you describe here is a sparge, not mashout.

How do you sparge (batch or fly)? Mashouts are generally only for fly sparging. If you're batch sparging, there's really no temperature requirement for the sparge water - studies have shown that even room temp water works just as well. Not that there's anything wrong with using 168²F water, but there's no reason to target that temperature specifically.

If you're fly sparging, then what you describe is not really a mashout at all. A mashout would be a smaller amount of near boiling water to raise the grain bed to ~168°F in order to halt the conversion process since sparging will take place over the next hour (give or take). My mashout volume is usually between 1.5-2.25 gallons depending on how big the beer is. This gets mixed into the MLT about 15 minutes before fly-sparging.

I use Beersmith for my mash calculations. I think I have it set to give me 1.3 quarts per pound of grain. (I batch sparge) I then drain the tun after the mash and measure the volume that I have collected. I know that I boil off 2 gallons per hour with my equipment. I then sparge (with 168 degree water) with about half of what I need to get to my preboil amount. I then measure the collected wort volume again and sparge with enough to get to my preboil volume.

So, I know that I need just over 7 gallons preboil to end up with just over 5 gallons into the fermenter. I don't worry at all about what the recipe/calculator tells me I need for sparge water.

MagicMatt said:

Just want to avoid confusion (and maybe save you some time), but what you describe here is a sparge, not mashout.

How do you sparge (batch or fly)? Mashouts are generally only for fly sparging. If you're batch sparging, there's really no temperature requirement for the sparge water - studies have shown that even room temp water works just as well. Not that there's anything wrong with using 168²F water, but there's no reason to target that temperature specifically.

If you're fly sparging, then what you describe is not really a mashout at all. A mashout would be a smaller amount of near boiling water to raise the grain bed to ~168°F in order to halt the conversion process since sparging will take place over the next hour (give or take). My mashout volume is usually between 1.5-2.25 gallons depending on how big the beer is. This gets mixed into the MLT about 15 minutes before fly-sparging.

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I see your point, but I have to partially disagree. I'm talking about batch sparging. However, if you can do a batch sparge AND achieve mashout temperature and thus kill off all the enzymes, then you've simulataneously sparged AND mashed out at the same time. If I did this and then wanted to walk away for a few hours, I wouldn't worry about over-conversion / high attenuation, because the enzymes would be gone. Now of course, typically there would be no reason to walk away and not finish brewing right then but it could happen and has happened. Sometimes the day does get interrupted, so in cases like those, a mashout could be useful even for batch spargers.

Personally, I don't usually fret over exact end-of-mash or "mashout" temperatures because I'm going to get the wort boiling in a matter of minutes anyway. On the rare occasions when I do measure sparge temperature, I usually find it has fallen to mid-160s just by sitting around in the mash tun and being stirred, etc., so you're also kind of right, what I recommend may or may not be a "real" mashout, depending on the goal and the true sparge water temperature. However I know that if I chose to use boiling water instead of just 188-190 F, then the enzymes would surely be goners and I would indeed consider that as being a true mashout, even if it doesn't matter! Whether it matters or not is completely up to the brewer and whether they need to take a break in the middle of the brewing session or whatever.

I also agree that for batch spargers or BIABers, mashout is unnecessary, as yes, you can still get all the gravity you want from sparging even with room temperature water, yadda yadda. Mashout does matter more with fly sparging. That I agree with completely.

I think we could be causing more confusion for some than clearing anything up! So, if anyone doesn't understand what we're talking about, then please feel free to ignore! This is honestly all pretty high-level unessential crap for most brewers.

Cheers.

I agree with everyone here. I used to never calculate strike/sparge volumes because...well, I guess I was never taught the right way. After the good folks here directed me down the right path, I'm all good now. Here's the math I do...

Strike Water = 1.5 quarts per pound of grain

First Runnings = Strike volume - absorption (0.13 gal/#grain) - dead space (0.25 gal)

Desired preboil volume - first runnings = sparge volume

Plenty of other ways to do it. But this is what works for me and I keep these formulas on my brew day "cheat sheet."

kev211 said:

First off... 200 degree water is way too hot for sparge. Sparge at 170. All you need to do is rinse the grains and stop the conversion process. 170 water will be fine for that and wont extract tannins.

Also, I think your calcs are a little off. I think 1/2gal per lb is too much water.

For 13 lbs of grain your total water should be somewhere (according to my calcs) around 8.8gals.

4.3 gals mash (1.33qt/lb)
4.5 gals sparge

Resulting in about 6.5 gals pre-boil.

Check out This Website. The water calculator works really well, I use it every batch and pretty much nail my numbers


One thing you can always do is run your mash, heat up more sparge water than is needed and add as much to the grains as you need to hit your pre-boil numbers, keeping in mind you should get pretty close to 100% of the sparge water into the boil kettle (no grain absorption at this point)

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200F water is not necessarily too hot for sparge. I often sparge with water in that temp range.

Denny said:

200F water is not necessarily too hot for sparge. I often sparge with water in that temp range.

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Im just basing it off what a brewer at Karl Strauss told me. He said that he recommends keeping it around 170 and not to break 180

I think what Denny is saying is that while it may (debatably) not be optimal, it's not going to ruin your beer or anything.

From what I've seen the greatest risk of sparging with "very hot" water (200+°F) is bursting unconverted starch granules resulting in a beer that's hard to clear, and you might get extra (unwanted) tannin extraction.

You'll see a lot of people telling you that the tannin extraction thing is a myth, because "how come I don't get tannin extraction when I decoction mash?!?!" I've researched this a bunch and it seems the reason is because you still hit a sacc rest to finish converting the remaining starches.

A mash out raises the temperature to 168–170 °C (76–77 °C), and during subsequent running off of the wort, and rinsing the grain bed with sparge water, the pH of the wort in the grain bed rises. If the pH rises to 5.8 or above, the combination of heat and high pH will cause tannins to be extracted at an unacceptably high rate. By keeping the temperature below 170 °F (77 °C) and the pH below 5.8, you can keep tannin extraction during wort collection to a reasonable level.

One thing to note: the temperature of the actual mash during the sparge is more important than the temperature of the sparge water, so one could take from this the notion you could use as hot a sparge as you wanted as long as the resulting mash does not exceed 170°F.

P.S. "Tannin extraction" is sort of a misnomer, really - it's actually that polyphenolic compounds are more easily solubilized in solutions approaching pH 6.0. This is easily addressable though by simply treating your sparge water with lactic or phosphoric acid to hit ~5.5 pH.

MagicMatt said:

I think what Denny is saying is that while it may (debatably) not be optimal, it's not going to ruin your beer or anything.

From what I've seen the greatest risk of sparging with "very hot" water (200+°F) is bursting unconverted starch granules resulting in a beer that's hard to clear, and you might get extra (unwanted) tannin extraction.

You'll see a lot of people telling you that the tannin extraction thing is a myth, because "how come I don't get tannin extraction when I decoction mash?!?!" I've researched this a bunch and it seems the reason is because you still hit a sacc rest to finish converting the remaining starches.

A mash out raises the temperature to 168–170 °C (76–77 °C), and during subsequent running off of the wort, and rinsing the grain bed with sparge water, the pH of the wort in the grain bed rises. If the pH rises to 5.8 or above, the combination of heat and high pH will cause tannins to be extracted at an unacceptably high rate. By keeping the temperature below 170 °F (77 °C) and the pH below 5.8, you can keep tannin extraction during wort collection to a reasonable level.

One thing to note: the temperature of the actual mash during the sparge is more important than the temperature of the sparge water, so one could take from this the notion you could use as hot a sparge as you wanted as long as the resulting mash does not exceed 170°F.

P.S. "Tannin extraction" is sort of a misnomer, really - it's actually that polyphenolic compounds are more easily solubilized in solutions approaching pH 6.0. This is easily addressable though by simply treating your sparge water with lactic or phosphoric acid to hit ~5.5 pH.

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This is great and exactly what I would have wanted to say but probably a little better. A lot of those one liner warnings have so much more going on. Great post.

Another thing to keep in mind is that MagicMatt inherently assumes that everyone is fly sparging, while Denny and I are batch spargers and tend to assume that more people batch sparge. There are some differences between fly and batch sparging that all of us often forget to mention and recognize based on our own biases.

kev211 said:

Im just basing it off what a brewer at Karl Strauss told me. He said that he recommends keeping it around 170 and not to break 180

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He's likely referring to tannin extraction in a fly sparged lauter. In fly sparging, your pH will continually rise and could cause you to extract tannins. But if you keep the pH in line, the temp doesn't really matter. If it caused problems getting over 170F, no one could ever do decoction mashes.

MagicMatt said:

I think what Denny is saying is that while it may (debatably) not be optimal, it's not going to ruin your beer or anything.

From what I've seen the greatest risk of sparging with "very hot" water (200+°F) is bursting unconverted starch granules resulting in a beer that's hard to clear, and you might get extra (unwanted) tannin extraction.

You'll see a lot of people telling you that the tannin extraction thing is a myth, because "how come I don't get tannin extraction when I decoction mash?!?!" I've researched this a bunch and it seems the reason is because you still hit a sacc rest to finish converting the remaining starches.

A mash out raises the temperature to 168–170 °C (76–77 °C), and during subsequent running off of the wort, and rinsing the grain bed with sparge water, the pH of the wort in the grain bed rises. If the pH rises to 5.8 or above, the combination of heat and high pH will cause tannins to be extracted at an unacceptably high rate. By keeping the temperature below 170 °F (77 °C) and the pH below 5.8, you can keep tannin extraction during wort collection to a reasonable level.

One thing to note: the temperature of the actual mash during the sparge is more important than the temperature of the sparge water, so one could take from this the notion you could use as hot a sparge as you wanted as long as the resulting mash does not exceed 170°F.

P.S. "Tannin extraction" is sort of a misnomer, really - it's actually that polyphenolic compounds are more easily solubilized in solutions approaching pH 6.0. This is easily addressable though by simply treating your sparge water with lactic or phosphoric acid to hit ~5.5 pH.

Click to expand...

No, it's becasue of pH.

Denny said:

He's likely referring to tannin extraction in a fly sparged lauter. In fly sparging, your pH will continually rise and could cause you to extract tannins. But if you keep the pH in line, the temp doesn't really matter. If it caused problems getting over 170F, no one could ever do decoction mashes.

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Possibly. But when I asked him regarding a 5 gallon batch sparge, what temperature he recommends he responded "I would always keep the sparge close to 170. You can go higher, but dont need to and its good to get into a common practice"

kev211 said:

Possibly. But when I asked him regarding a 5 gallon batch sparge, what temperature he recommends he responded "I would always keep the sparge close to 170. You can go higher, but dont need to and its good to get into a common practice"

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OTOH, there's nothing wrong with it, either. OTOOH, you can sparge with room temp water and it won't make a difference.

Otooh... Lol

The only reason you would ever want to do a 200° sparge, is when you want to do a mash out and you do it while stirring the grain bed.
Tannins can be extracted by oversparging, sparging at too high a temperature (greater than 170 F or 77 C), or mashing at too high a pH level. pH levels above 5.5 are particularly prone to tannin extraction, with 5.1 or 5.2 being an ideal pH level during the mash. So even when you keep the pH in line the temp REALLY DOES MATTER. Sparging does indeed increase the pH of the pH of the grain bed over time even at 170°. However this does NOT mean that you can sparge at whatever temperature you like as long as you keep your pH in check. Tannins get extracted during the whole mashing process but high pH, mashing to long, oversparging AND HEAT are all causes for getting more tannins in your beer.


Now, back to the OP's question:

whille it has been kinda a standard rule of using .5 gal/lb of grain for sparging I found some calculations a while ago for sparging. They're not mine but I don't really remember where I got them. It was either from beersmith or from Brew Your Own.
I need to make some assumptions cause I don't know your brewing set up so please do not use these, but figure them out yourself for the best results.

Warning this can get complicated!

• I'll start with some numbers we might need later:

assumption 1: average volume of grain is 0.32 qt/lb
assumption 2: every pound of grain absorbs about 0.5 quarts of water. This depends on the kind of grain and the moisture content of the grain but 0.5 is kinda standard

Based on your information:
fermentables: 13 lbs
strike water (let's go with 1.25 qt/lb of grain): about 4 gallons or 16.25 quarts.
Boil volume: 8.5 gallons or 34 qt

• Values we'll need:

Total mash volume: volume of water + volume of grain.
Volume of water absorbed by grain: 13*0.5= 6.5
Average volume of grain when mashing: 0.32 qt/lb so in your case this would be 4.16 qt/lb + 16.25 = 20.41 qt or 5.1 gallons.

• Sparging water:

assumption 1: 2 qt/lb of grain= 26 qt or 6.5 gallons
assumption 2: -volume of liquid remaining in the bottom of mash tun (after draining the first runnings) 1 qt
assumption3: volume of liquid remaining in lines = 0.25 qt


But we would like to know the volume of the first runnings we drain before we add the sparge water.

Volume of first runnings = Strike water volume + volume of any other water added to the mash prior to sparging - volume of water absorbed by the grain - volume of liquid remaining in the bottom of the mash tun - volume of liquid remaining in lines:
16.25+0-6.5-1- 0.25= 8.5 qts of first runnings.

Total volume of sparge water

Target pre-boil volume - volume of first runnings:

34 qt- 8.5 qt =25.5 qt
add to the calculated value the volume sparge water left in your sparge water tank (below the valve) if you use one.

If you batch sparge, sometimes the mash tun won't be large enough for the entire volume of sparge water to be added in a single batch. The usual procedure is to divide the total sparge water required into equal batches based on the vessel’s useful capacity and the volume of the mash after the first runnings are drained. The formula for calculating the number of batches required is:

Number of sparge water batches = (Volume of sparge water - volume of sparge vessel dead space(water below the valve))/(sparge vessel useful capacity - volume of grain - volume of water absorbed by the grain)

Because i don't know the capacity of your your mash tun I can't really calculate this but this formula ain't rocket science
just remember to round up to the next whole number.

• Total water needed

Volume of strike water+volume of any additional mash water infusions+volume of sparge water (including sparge water vessel dead space) +water added to the kettle pre-boil+water added to the kettle or fermenter post-boil.


So based on this,
you would need 25.5 qt of sparge water or 6.3 gallons + sparge water left in your sparge tank if there is any.

If a recipe uses another mash thickness than you have to change that value when you calculate your strike water.

You could have just pointed him to the BYO article you essentially copypasta'd without citing: https://byo.com/bock/item/410-calculating-water-usage-advanced-brewing

Maybe a little off topic, but I think this might be relevant.

I skimmed through here, and it doesn't look like anyone has said anything as far as to just stop sparging when your runnings hit 1.012 or 1.010. Isn't that a decent rule of thumb to go by? I know it is a bad assumption to make that everybody trying all-grain brewing would have a hydrometer, but maybe that could be included for those that do (if it isn't already)? I guess it would make things a little trickier for those who batch sparge, though.

I tried to find "magic formulas" a while ago for how to batch sparge and as I went I thought about the kinds of brews I've seen people make. Super-light worts for berliner weisse to high gravity wort for bocks. I felt like trying to just plug it in to a formula that relied on hitting a set pre-boil volume could lead to oversparging what should become light worts and undersparging what should be high-gravity worts. So I'm glad that the original formula used in this post didn't include anything about hitting a final volume.

As far as the original post: I guess I've missed some debates around here as far as what water to grist ratio to use, but I always try to keep it thinner than 1.25qts/lb. Usually around 1.35qt/lb all the way up to 2qts/lb. There was a time I tried to do a step mash and I figured I better dough in thick to start, and I don't know if I even saturated the grist by going 1:1.

I also think sparging with half a gallon of water per pound grist would make it a little dilute. What stickies are you referring to?

There is some debate about sparge water temperatures, and even though I don't take brulosophy experiments as gospel, I do find this encouraging. What I took from that is that I am fine if I sparge with water between 145F to 165F.

dmaddox said:

Why then, does every recipe I find - not follow that rule at all - or am I misunderstanding?

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I think I strayed from the original question with my last post.

Without going further into the merits of the specific instructions themselves, the instructions you read are from a brewer (or a group of brewers) who is citing the instructions that work for him or her.

But the thing is, there are a lot of factors that change from brewer to brewer and even brew to brew. You may not be using the same equipment as the brewer(s) that posted those instructions, which can have an impact on what you make. For example, that brewer might use a heating source and kettles that cause a significant amount of evaporation during the boil. I suppose even elevation the brew occurs at could mess with this.

But even the ingredients you use change from time to time. Maybe you're planning to just use regular tap water (which, more than likely, can make great beer for you) but the person writing the instructions uses RO purified water and adds specific minerals in specific quantities, which can impact efficiency.

Even time is a factor. Sometimes water in the spring, while the snow is melting, has different mineral content than it does in early fall. Barley and hops have slight, usually negligible variations from region to region and year to year depending on their growing conditions.

Without accusing anybody of anything, sometimes the brewer just messes up when he or she tries to pass a method on to a new person. Maybe something got messed up during unit conversions, or maybe there was a typo. And preferences for certain methods come up, like fly vs batch sparging. Or decoction vs step mash vs single infusion. How weak or strong of beers the brewer typically makes. The level of detail the brewer goes into when he or she explains things also comes in to play. For instance, I just replied to someone in a post maybe a day ago and when I woke up the next morning I thought "wow, did I just go into *way* to much detail and potentially scare someone away from the hobby?".

So there are a lot of variables that can become a factor. IMHO the best things to keep in mind are:

• You can make good beer from good malt, drinkable and good tasting water, fresh hops, and pure & active brewers yeast.
• While there are a lot of variables to factor in, brewing books and internet searches are great.
• If a method is good enough that it makes it into a current and reputable homebrew book, it is probably good.
• If a method is good enough that an internet search provides a few articles from good sources that describe it in basically the same way, it is probably good.
• If a method passes either of those tests and you feel good about it, go for it.

Kent88 said:

Maybe a little off topic, but I think this might be relevant.

I skimmed through here, and it doesn't look like anyone has said anything as far as to just stop sparging when your runnings hit 1.012 or 1.010. Isn't that a decent rule of thumb to go by?

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It's a good rule of you fly sparge. If you batch sparge, it's unnecessary.