Tell me about your fly sparge

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TheMadKing

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I brewed today and had a realization that there's an aspect of fly sparging I've never considered. I'm curious to hear about how you fly sparge and let me explain.

I have a spike 3vessel custom system. I used to sparge (until today) as follows: When it comes time to sparge I mostly follow spike's directions and pump my hot 168F sparge water from the HLT through the HERMS coil into the mash tun where it flows down onto the grain bed through a piece of silicon tube and distributed by one of those flexible aquarium aerator manifolds.

Per spikes directions I start a slow runoff to the boil kettle and begin adding hot sparge water and try to balance the flows. I keep 1 inch of water over the grain and try to make my sparge take about 30-45 minutes. I sparge until I hit preboil volume in my kettle. I've spoken to several fellow brewers and they all agree that they sparge until they hit preboil volume.

Today I brewed a barleywine and followed almost all the same steps except for the end. I kept 1 inch of water over the grain but it also bed monitored my HLT to see how much sparge water I was adding. I stopped the flow of sparge water when I hit the BeerSmith recommended 2.5 gallons of sparge water. Then I just left the wort flow alone and let it slowly drain.

I was doubtful that I would hit my preboil volume like this without adding more water but sure enough, it was right.

I also hit 69% brewhouse efficiency and 77% mash efficiency in a beer with an OG of 1.105!! That's crazy high for me, and I was predicting only 64% brewhouse efficiency.

I believe that for years I have been excessively diluting my wort by keeping 1" of water over my grain bed and sparging until I hit preboil volume instead of paying attention to BeerSmith and stopping my sparge water flow.

What do you do?
 
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I measure my water volumes to the qt, rounding up a bit, before mashing in. When my sparge is almost done I let the rest of the sparge water empty into the mash tun and keep drawing wort until I hit my pre-boil volume. I get 80% mash efficiency and 78% brewhouse with my 3v igloo system.
 
I measure my water volumes to the qt, rounding up a bit, before mashing in. When my sparge is almost done I let the rest of the sparge water empty into the mash tun and keep drawing wort until I hit my pre-boil volume. I get 80% mash efficiency and 78% brewhouse with my 3v igloo system.

Thanks! So you've always limited your sparge volume. Do you usually have extra liquid left in your mash tun when you're done sparging?
 
fwiw, I use the same procedure as detailed above, and typically end up with a quart or two under the FB when all is done. Not too shabby as by the time I note the remaining liquid it's about 20 minutes post-lauter and the remains are on the way to the compost pile.

Before (and for a few years) I'd run the sparge liquor all the way 'til my pre-boil volume was reached. The problem with that rather silly method is now one has to wrestle the MLT with a few multiples of 8+ pounds per remaining sparge liquor gallon through whatever disposal process is used. Not fun...

Cheers!
 
fwiw, I use the same procedure as detailed above, and typically end up with a quart or two under the FB when all is done. Not too shabby as by the time I note the remaining liquid it's about 20 minutes post-lauter and the remains are on the way to the compost pile.

Before (and for a few years) I'd run the sparge liquor all the way 'til my pre-boil volume was reached. The problem with that rather silly method is now one has to wrestle the MLT with a few multiples of 8+ pounds per remaining sparge liquor gallon through whatever disposal process is used. Not fun...

Cheers!

Ah see I was just running off any excess down my driveway before scooping grain from my MLT so no added weight for me

If it had been that much of a pain I would have figured it out quicker!
 
Do you usually have extra liquid left in your mash tun when you're done sparging?

Hardly any. By the time I’m done the grains are exposed. When I start cleanup I open the ball valve and get maybe a pint of liquid max out of the mash tun. My goal is generally to have just enough water for my whole process. I use 5 gal coolers for space/storage reasons so I often have just enough room for the whole run and have an upper limit of about 1.060 OG. But it’s what works for me.
 
It sounds like this idea to add sparge water continously all the way to preboil volume is a newer idea born out of convenience at a cost to efficiency and possible over sparging/tannin extraction. The other brewers in my club that do it use all in one systems like anvil or grainfather or similar to the spike system.

I used no-sparge BIAB up until I got my spike system so I never had to learn to do it any other way. Stupid little thing but it's a big boost on a barleywine
 
i've always assumed the sparge water was like a squigy of sorts, pushing the sugar down and out, and off the grain? never been worried about extra in the mash tun...sugar does dissolve but slowly so the sparge water kinda pushes the sweet wort out. at least that's what i've always thought.
 
Kind of. But unless your runoff is 100% perfect (which none are), any channeling paths mean you're pulling more dilute wort from above at the same time as sweeter wort below. Minimizing the liquid left in the lauter means maximizing available sugars by draining out as much as possible.
 
Kind of. But unless your runoff is 100% perfect (which none are), any channeling paths mean you're pulling more dilute wort from above at the same time as sweeter wort below. Minimizing the liquid left in the lauter means maximizing available sugars by draining out as much as possible.

well i guess i do a hybrid batch/fly sparge because i just scoop my sparge water into a colander on the grain, and it runs dry a few times durring my sparge...but i get 10 gallons of ~1.067 wort, from 20lbs malt, so i haven't changed my method. i do let the water soak for a few minutes when it bubbles when added to let it mix....
 
@TheMadKing I don't think you mentioned in your process, but before adding any sparge water, do you completely drain your mash tun to collect the "first runnings"?

I batch sparge now, but when I was fly sparging, I would drain the mash tun completely, close the valve, then add sparge water until the 1" under water like you mention, and start the flow. I used brewing software to calculate sparge water volume, so at the end of sparge, my grain would no longer be under water, and I would have very little liquid in my mash tun.
 
oh i can add, i find i know i hit the sweet spot with a second step at 162f, when the malt sinks and the wort is above the grain bed during the mash, not even the sparge....
 
@TheMadKing I don't think you mentioned in your process, but before adding any sparge water, do you completely drain your mash tun to collect the "first runnings"?

I batch sparge now, but when I was fly sparging, I would drain the mash tun completely, close the valve, then add sparge water until the 1" under water like you mention, and start the flow. I used brewing software to calculate sparge water volume, so at the end of sparge, my grain would no longer be under water, and I would have very little liquid in my mash tun.

No I don't do that, I start the sparge and the runoff simultaneously. What you're describing is essentially a batch sparge without stirring though

If I did that I would add too much sparge water because I only needed 2.5 gallons total which isn't enough to cover my grain bed. I think that's one of the limitations of batch sparging actually, is that it inherently uses more water so you get more dilution.

The RATE of sparging is key as well. Sparging is not pushing sugar from the grain like Brac described above, it's actually pulling sugar into the water using osmotic pressure. So you are reducing the concentration of sugar outside the grain particles and forcing it to migrate through the grain into the water. If you sparge too fast then you don't give this process enough time. Another hazard of fast sparging is that it mixes the runoff and or causes channeling rather then letting it slowly stratify into a gradient.
It should take 45-60 minutes regardless of system size and that's my new target.

So what I'm going for is that sugar gradient through my grain bed with low sugar at the top and high sugar further down. As the sparge progresses the gradient moves down through the grain bed. My issue before, was that I was continously adding fresh water so I was diluting my final runnings and they weren't as concentrated as they could have been.

So when I cut off my sparge water now, without changing my runoff speed, that low sugar layer slowly sinks through the grain bed getting more concentrated as it goes down. That puts the most sugar into the boil kettle because I'm not hitting my preboil volume until the very end and the sugar concentrations are still relatively high.
 
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My apology in advance for going :off:.
So here's a question for you fly spargers: Do you really notice much of a difference in the beer? I used to do a fussy, lengthy fly sparge but then when I heard about batch sparging (years ago) I tried it and didn't notice any difference in the beer so I quit fly sparging.
Recently, I've gone with short and shoddy type small batches and still do a "dunk sparge" with a BIAB mash, and the beer is still fine, although I'm wondering if I drag my old fly sparging gear out and do a side by side evaluation if I'll notice any difference.
My thinking these days is that good beer is more about recipe and ingredients and less about complicated equipment, methods and a lengthy brew day. When the BIAB method first appeared, I heard about many side by side comparisons with the traditional method that said they couldn't tell a difference. Has anything changed?
 
My apology in advance for going :off:.
So here's a question for you fly spargers: Do you really notice much of a difference in the beer? I used to do a fussy, lengthy fly sparge but then when I heard about batch sparging (years ago) I tried it and didn't notice any difference in the beer so I quit fly sparging.
Recently, I've gone with short and shoddy type small batches and still do a "dunk sparge" with a BIAB mash, and the beer is still fine, although I'm wondering if I drag my old fly sparging gear out and do a side by side evaluation if I'll notice any difference.
My thinking these days is that good beer is more about recipe and ingredients and less about complicated equipment, methods and a lengthy brew day. When the BIAB method first appeared, I heard about many side by side comparisons with the traditional method that said they couldn't tell a difference. Has anything changed?

So I used to BIAB and do the short and shoddy method for years and switch to 3-vessel with a fly sparge for a few reasons. Fly sparging, for me, is more about good practice and granted 90% of the time, I probably couldn't tell the difference between a fly sparged beer and a no-sparge beer with the same ratio of ingredients and the same OG. But I don't brew for 90% I brew to be the best brewer I can be 100% of the time and my priority is not lowest effort on brew day, it is producing the most consistent high-quality product I can make. There are some instances, over 100+ batches with both BIAB and with a 3-vessel system where I find that following "good practice" and emulating pro-breweries techniques has yielded more consistent quality in my beers.

I have also found that varying mash thickness has an effect on enzyme activity and malt character, my efficiency (especially with big beers) has greatly increased, my shelf stability has increased which I credit to better cold side techniques and less trub into the kettle thanks to the vorlauf, and I genuinely enjoy my brew days, so the sparge is all part of the fun. There are benefits to it IMO, but it's benefits to the last 10% of making good beer, not a fundamental shift in quality.
 
I target a 90 minute runoff, not 45-60. This is admittedly difficult to achieve on my home system where it typically ends up like 70 mins.

I would get almost as good of efficiency out of a double or triple batch sparge as I would out of a continuous sparge. Never that close with a single sparge. But triple batch sparging would take just as long and was more work. So only for partigyles.
 
I target a 90 minute runoff, not 45-60. This is admittedly difficult to achieve on my home system where it typically ends up like 70 mins.

I would get almost as good of efficiency out of a double or triple batch sparge as I would out of a continuous sparge. Never that close with a single sparge. But triple batch sparging would take just as long and was more work. So only for partigyles.

I have always gotten a few points higher with fly sparging than batch sparging for whatever reason. Yesterday's barleywine was the highest efficiency I have ever achieved accounting for the size of the grain bill (21.5 lbs for a 5 gallon batch) and I was able to hit 77% mash efficiency so I'm pretty darn happy with that.

I did a 2 hour boil though so that definitely helps.
 
I'm planning to make a 'sprinkler head' item for my Spike+ mash tun before next batch. I'm ordering some small TC caps (for 1/2" or 3/4" fittings, so 1" OD) that I'll machine and put on the end of a center pickup assembly/arm. I have three of the caps in my cart now. So if I screw up one, or even two, its NBD since I'll have another to use. I plan to see if I get any better temperature distribution during the recirculation of the mash this way. Since I'll also have the original setup, I can go between them.

I'm going with the 1" OD cap so that it will pass through the 1-1/2" TC ferrule in the kettle (1-3/8" ID). I know Brewers Hardware is working on an assembly that will do [essentially] the same thing, but I don't know how far out that is. I want to have this created, and tested, within the next couple of weeks.
 
After reading "How to Brew" after 8 years of brewing, I changed from a quick drain, sparge and drain again to a slow drain and reducing my pump to match the speed I'm drawing. Definitely bumped up my efficiency but slowed my brew time. Takes about 30-45 minutes draw the right volume out but I'd say it's worth it.
 
I did an experiment a few years ago, while I was dialing in my mash process using a Cereal Killer 2-Roller Mill, so I was looking at crush size. All 4 of these batches used grain from a single 55-lb bag of grain to minimize variation, doing a 60 minute mash at 150F. There will likely be variations within the assumptions for your own brewing process, but was some data I could share from my own experiment.

ProcessTimeMash Efficiency
No Sparge, 34 mil crush
20​
70.4​
1 Sparge, 34 mil crush
23​
75.3​
1 Sparge, 26 mil crush
23​
82.7​
20 min Fly Sparge, 26 mil crush
28​
83.9​
 
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@micraftbeer It would help if you included what you use for the MT. Since there's no frickin way I could do a .026" crush size with my Spike+ MT. They list .035" and .036" crush size as their starting points. I adjusted mine to .035" previous brew day and checked it again for Saturday's session. I might shift to .034" but don't want to go below that (or not much anyway). No point risking getting a plugged up false bottom.
 
@micraftbeer It would help if you included what you use for the MT. Since there's no frickin way I could do a .026" crush size with my Spike+ MT. They list .035" and .036" crush size as their starting points. I adjusted mine to .035" previous brew day and checked it again for Saturday's session. I might shift to .034" but don't want to go below that (or not much anyway). No point risking getting a plugged up false bottom.

Agreed and I run mine at .050

FWIW on an average gravity beer, 85-90% mash efficiency is pretty common
 
I'm running a 10 gal custom electric HERMS system with a 20 gal MT. I started out with fly sparges on a basic 5 gal system, and for no good reason stuck with it when I moved to the second system.

On the 5 gal system, I used the method originally described, ie did not measure fly sparge volume, though I usually didn't leave much in the HLT. I never calculated efficiency on that system, but I hit or exceeded OGs pretty consistently. Note that I did step mashes.

On the newer system, I started using BrewersFriend for recipes, calcs, etc. The system profile you build there includes various losses, and if you get those reasonably close, the calculators do a pretty good job with volumes and OG. So I now fly sparge the calculated amount, which is usually right on. Yesterday I forgot to measure pre-boil gravity, but OG was a point over, and efficiency was 80%.

I no longer step mash because the HERMS doesn't move the mash temp fast enough, plus everything I read says it's not necessary with modern malts. So I do a low mash-in (upper 140s) for 30 min, then raise temp over the next 30 min to 172F.

One comment from the original post had me mystified until I read the Spike setup instructions - reconnecting your hoses so that your sparge water circulates through the HERMS coil on the way to the MT. I guess there is a benefit in terms of capturing the wort in the coil as well as cleaning. Will have to try it next time. This is a Brucontrol setup, at some point I want to get more powered valves in place and stop disconnecting hoses mid-brew, which has never, ever caused any massive messes. Ever.

- Gregg

On tap: Imperial multigrain farmhouse, Quad, NE Farmhouse IPA
In process: Saison
 
@Golddiggie Thanks for that question. Made me go back through my files. The table I provided previously was an efficiency study I did on my 2-roller (Cereal Killer) mill, while mashing in my Spike+ Kettle with their standard false bottom. That said, after I had settled in on that 0.026" crush, I was periodically getting stuck mashes while trying to recirculate through my RIMS. So I then did a product review on the 3-roller Monster Mill MM-3, seeing if I could get good efficiencies without going as fine on the crush. Since the MM-3 review was done at a different time, with different batch of grains, the Mash Efficiency numbers can't be directly combined/compared between the two experiments. And by the time I did the MM-3 review, I had already settled in on my process of 1-sparge batch sparge method, so I don't have different process data for that.

All of that said, here's the 2 sets of data:

1631050962503.png
 
I vorlauf about a gallon first. Then I fly sparge from the HLT into a Phil's sparge arm. I have a Brewtech recirculation manifold for mashing and I think I could use that but like @csantoni I think the sparge arm is more fun! The hose is also smaller diameter and I can slow things down better too. I cut the flow of from the HLT when I estimate there is enough water to reach my preboil volume. I've also done the leave the HLT open until preboil volume but for several reasons don't do that. First I completely agree with @day_trippr that SOB MLT is heavy! I have a keggle and hauling that beast up the steps to the tumbling composter is a real bear. The yard compost pile is even farther. I used to just drain the MLT in the driveway and wash it out there to but the runnings and spent grain attract rats. Mostly the grain though but that's why the spent grain goes in the tumbling composter (sealed) and not the yard. Also, my dog will eat it from the yard compost bin and get even fatter. The last reason is that, and this may not be described scientifically accurately, but here goes. I figured I was leaving sugars behind by keeping the sparge water flow going until the end. My thoughts are that near the end, the liquid leaving the MLT is most likely unsaturated and can keep absorbing sugars into solution. A residual volume of water in the MT means that the last bit of volume making its way to the BK is more dilute than if you get it just right. I think that would be true at least for the liquid under the the MT false bottom and somewhat true for the liquid above it.

So I estimate when I need to close the HLT valve and if I am over or under preboil volume I just adjust the power on the BK to get to the volume I need in the end.
 
How do these methods compare with a BIAB system and continuous sparge?
 
@Mad Mann I've got data from another review for that. This one is straightforward enough that I'll try not to screw up my data. From my review on the Anvil Foundry 6.5, I mashed 3 ways- 1) no recirc, 2) with recirc and full volume mash, and 3) with recirc and single sparge:

I used a simple mash of 5 lbs of Viking Xtra Pale Malt and 0.3 lbs of Briess 2-row Brewers Malt, along with brewing salts + acid to hit a mash pH of 5.57. The grains were from the same 55 lb sack of each malt. I mashed for 1 hour at 149F, followed by a ramp up to 168F for a 10 min mash out. I mashed 3 different batches: 1) Full volume mash, no recirc, 2) Full volume mash with recirc, 3) Loose mash with 2.4 qt/lb with recirc followed by 1.5 gal sparge poured through the mash basket while up on its posts. The mash efficiency difference was striking. The full volume mash without recirc achieved 72%, with recirc it increased to 74%, and the recirc + sparge reached 87%. From this data, it would appear that the sparge made a significant effect. Unfortunately, I didn’t have enough of the same batch of grain to do a 4th combination of no recirc + sparge.
 
Sorry, should have been more specific :) Continuous recirculation with full volume of water and no spare.
Recirc might improve your conversion efficiency a bit, if you don't have almost 100% conversion efficiency already. The mechanism is increasing the rate of conversion slightly, which can give more total conversion, if the mash time is not sufficient for complete conversion without recirc. You should be able to obtain the same conversion efficiency with a longer mash, if recirc is increasing your conversion efficiency.

Recirc during the mash will not improve your lauter efficiency. Since mash efficiency equals conversion efficiency times lauter efficiency, improving either conversion efficiency, and/or lauter efficiency, will increase your mash efficiency. Sparging increases your lauter efficiency, but has no effect on conversion efficiency.

The data from @micraftbeer in the post above is consistent with what I have written above. If you do a tolerance analysis on efficiency calculations, you will find that any single measurement has a probable error of about +/- 3 - 4%. Thus the measurements of 72% for no recirc and 74% for recirc are not significantly different.

Brew on :mug:
 
Now this has me thinking about changing from my Monster Mill two roller (2" diameter, hardened steel) crusher to one of the three roller versions. I was looking at them earlier and the one I'm more likely to get is showing as shipping within 45 days. I already have their motor on my MM2 (I made a riser for it so that the shaft of the motor properly aligns) so I would just need the mill set up to work with that. I just need to decide if the geared version is worth the extra $130 sticker price.
 
I like to keep if fairly simple but accurate:

About 20 min before Mash Out I crank up the HLT to 190*F
5 min before Mash Out I start the recirculation (this process I do as absolutely fast as my pump will run full open to set my grain bed)
While this is going on I calculate my needed sparge water and sparge speed.
CALCULATING sparge speed I TARGET 45 MIN
(Qts needed for pre boil divided by time)
Normal 12 gallon batch is 14 gallons pre boil or 56 qts so about 1.25 QTS per min.
While recirculation is setting grain bed I drop about a gallon of liquor into the MLT to raise temp and to raise volume to about 1" above mash. Set my HLT to proper volume and sparge temp. (I have landed on 175*F but that for another discussion)
Set the incoming float switch and outgoing speed, fire up a cigar and let the system work. :)

Cheers
Jay
 
Sorry, should have been more specific :) Continuous recirculation with full volume of water and no spare.

The purpose of recirculating is to maintain or change your mash temp and is not intended to have an effect on efficiency.

In fact recirculating tends to drop people's efficiency because it is very easy to cause channeling which reduces both conversion and lauter efficiency unless the brewer re-stirs the grain bed periodically. So unless the brewer let's the grain bed set, and then recirculates at a slow enough speed not to cause channeling, it does more harm than good
 
Now this has me thinking about changing from my Monster Mill two roller (2" diameter, hardened steel) crusher to one of the three roller versions. I was looking at them earlier and the one I'm more likely to get is showing as shipping within 45 days. I already have their motor on my MM2 (I made a riser for it so that the shaft of the motor properly aligns) so I would just need the mill set up to work with that. I just need to decide if the geared version is worth the extra $130 sticker price.

Wait, which discussion made you want a new mill?

I honestly don't understand the purpose of expensive 3 roller grain mills unless you are processing 20+ lb of grain regularly. The crush itself is still just a crush, it will just do it faster
 
I like to keep if fairly simple but accurate:

About 20 min before Mash Out I crank up the HLT to 190*F
5 min before Mash Out I start the recirculation (this process I do as absolutely fast as my pump will run full open to set my grain bed)
While this is going on I calculate my needed sparge water and sparge speed.
CALCULATING sparge speed I TARGET 45 MIN
(Qts needed for pre boil divided by time)
Normal 12 gallon batch is 14 gallons pre boil or 56 qts so about 1.25 QTS per min.
While recirculation is setting grain bed I drop about a gallon of liquor into the MLT to raise temp and to raise volume to about 1" above mash. Set my HLT to proper volume and sparge temp. (I have landed on 175*F but that for another discussion)
Set the incoming float switch and outgoing speed, fire up a cigar and let the system work. :)

Cheers
Jay

That's a thing of beauty!

Except I think you're probably creating channels in your grain bed by recirculating that fast, rather than setting it with uniform porosity 😉

Glad to see you chatting again Jay!
 
Wait, which discussion made you want a new mill?

I honestly don't understand the purpose of expensive 3 roller grain mills unless you are processing 20+ lb of grain regularly. The crush itself is still just a crush, it will just do it faster

He may have been referring to my discussion above about mill gap settings and mash efficiency. If you want more detail about the 3-roller mill, in my review link below I have pictures of the different grain crush between 2-roller and 3-roller set at different gaps. As I noted in that review, I could visibly see better crush with the 3-roller mill (all grains at least cracked), and have avoided the stuck recirc I would occasionally get from crushing finer on my 2-roller.

https://www.homebrewfinds.com/2020/04/hands-on-review-monster-mill-mm-3-grain-mill.html
 
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