Is my fly sparge a waste of time? Need help and common sense!

[luckybeagle]

I'm currently brewing a Belgian style Tripel with a 25# grain bill (10.5 gallon batch, mostly pilsner malt) on my 15 gallon eHERMS system. After 8 batches on this system and 80 or so to my name, this was the first time I ever messed with my mash pH. I noticed it was high (6.2 about 10 minutes into the mash), so I added a few ML of Lactic Acid and reduced it to 5.5ish. I also treated my sparge water down to about 5.4-5.6 pH. The water coming from my tap is 7.4, and my efficiency has been poor, so I thought I'd start there.

I mashed at about 151F for 75 minutes and recirculated through my herms coil the entire time. I fly sparged to a 12 gallon preboil volume over the course of about an hour, stirred up the boil kettle and took a gravity reading. After adjusting for temperature, I came up with a preboil gravity of 1.064. This is 4 points lower than my intended preboil gravity at a conservative 78% efficiency. I thought for sure I'd land north of 80% and would have to dilute. My actual efficiency after taking these numbers into account is 73%. My previous batch was about 75% and a Trappist Single I brewed earlier this year was in the mid 80's.

It's strange to me that, on this system and with this process, I'm essentially getting my old batch sparge efficiency on a much more complex and time consuming system. I built it about 90% to specs of Kal's system (theelectricbrewery.com), and he's averaging 88 - 95% efficiency on his batches. Assuming the roller settings at my LHBS hasn't changed, what in my process is causing such crummy numbers? I'm slightly annoyed that they're unusually low, but really frustrated that I can't seem to hit my #s on any batch and need to make BU:GU, boil time and volume adjustments on the fly.

As low tech as batch sparging was, I'm thinking of going back to that method (on this system). Any thoughts from the forum wizards?

 

[doug293cz]

First off, a larger beer (higher OG, larger grain bill) will always have a lower mash efficiency (lauter efficiency specifically) than a smaller beer for the same pre-boil volume, for the same process. There is nothing you can do about this. So, you can really only compare efficiencies for beers with the same grain bill weight to pre-boil volume ratio.

Mash efficiency equals conversion efficiency times lauter efficiency, so to diagnose low mash efficiency, you need to know if it is your conversion efficiency, or lauter efficiency that is lower than it should be.

Conversion efficiency should be 90% or better, and 95% or better is readily achievable. You can measure your conversion efficiency using the method here. You then use your brewing software to calculate your mash efficiency, and calculate lauter efficiency as mash efficiency divided by conversion efficiency. The primary methods for improving conversion efficiency are to crush finer (up to the point where you start getting stuck mashes/sparges), and/or extending the mash time to get more conversion.

The theoretical maximum lauter efficiency for no-sparge/batch sparge is shown in the chart below. A traditional MLT has a grain absorption rate of about 0.12 gal/lb, so the solid lines are what should be compared against. A well done fly sparge should have slightly higher lauter efficiency than a triple batch sparge. If your fly sparge is not doing better than a single batch sparge, then you are wasting your time fly sparging. Poor fly sparging results are almost always due to channeling in the grain bed. Lack of a good false bottom, can be a cause of channeling.

Brew on

 

[RM-MN]

The crush of the grain is the most important factor in conversion efficiency. If you are relying on the LHBS to crush the grain you are paying twice for that service. First is the cost of the grain which will be cheaper in bulk than from the LHBS on a per recipe basis. Second is the lower efficiency that forces you to use more grain to get the same OG.

The mash pH seems like a good thing to be adjusting but it is a moving target. The pH does not stabilize for at least 15 minutes into the mash and at that time a good part of the conversion will have occurred. If you brew the same recipe regularly, take the mash pH at the 15 minute time and record that in the recipe, then make adjustments in the pH for the next batch. Adding the acid after the mash is underway doesn't help much and it doesn't have much effect on the efficiency.

Are you willing to make some changes (big changes) to your process to improve your efficiency? Get a mill, a cheap Corona mill. That will set you back about $25. Buy a bag from Wilserbrewer. Have it custom made to fit your boil pot. Do your mash in the boil pot. Try it with a small batch at first. You don't want to ruin a big batch by having the OG be way too high. Mill the grains as finely as possible with the Corona mill. Cut your mash time in half. Remove the bag from the mash and pour some water over it to extract a little more sugar. Check your OG.

 

[Bassman2003]

Just my opinion - chase beer flavor, clarity and process instead of efficiency. Unless you are trying to save money or your enjoyment of the hobby is a more technical pursuit, efficiency is not a measure of the brewer. Since you have a new system, I know that dialing in everything is important. Us homebrewers are not production brewers that need to meet a bottom line, so efficiency can be a choice.

I have made a lot of changes this past year in my brewing, and I am purposefully not focusing on efficiency. Try to emphasize the positives and other benefits the new system over the old system. If there are not many then maybe an assessment of why you moved to the new setup?

 

[Dog House Brew]

First off, a larger beer (higher OG, larger grain bill) will always have a lower mash efficiency (lauter efficiency specifically) than a smaller beer for the same pre-boil volume, for the same process. There is nothing you can do about this. So, you can really only compare efficiencies for beers with the same grain bill weight to pre-boil volume ratio.

Mash efficiency equals conversion efficiency times lauter efficiency, so to diagnose low mash efficiency, you need to know if it is your conversion efficiency, or lauter efficiency that is lower than it should be.

Conversion efficiency should be 90% or better, and 95% or better is readily achievable. You can measure your conversion efficiency using the method here. You then use your brewing software to calculate your mash efficiency, and calculate lauter efficiency as mash efficiency divided by conversion efficiency. The primary methods for improving conversion efficiency are to crush finer (up to the point where you start getting stuck mashes/sparges), and/or extending the mash time to get more conversion.

The theoretical maximum lauter efficiency for no-sparge/batch sparge is shown in the chart below. A traditional MLT has a grain absorption rate of about 0.12 gal/lb, so the solid lines are what should be compared against. A well done fly sparge should have slightly higher lauter efficiency than a triple batch sparge. If your fly sparge is not doing better than a single batch sparge, then you are wasting your time fly sparging. Poor fly sparging results are almost always due to channeling in the grain bed. Lack of a good false bottom, can be a cause of channeling.

View attachment 678413

Brew on

Can’t put it any better than that.

 

[luckybeagle]

Thanks everyone for the thoughtful advice!

First off, a larger beer (higher OG, larger grain bill) will always have a lower mash efficiency (lauter efficiency specifically) than a smaller beer for the same pre-boil volume, for the same process. There is nothing you can do about this. So, you can really only compare efficiencies for beers with the same grain bill weight to pre-boil volume ratio.

Thanks for the chart! That is interesting. I hear you on the higher OG beers resulting in lower efficiency.The Oatmeal Stout I made a couple weeks ago also had efficiency in the low to mid 70's, if I remember correctly. I only did a 5 gallon batch of that one, too. 10 lb grain bill, mashed at the same mash thickness (1.5 after taking the false bottom into account). I suppose that could be more tied to the grain bill. For some reason I did much better on a different Tripel that I brewed back in February--one of my first beers on the system and I hit 83% or so. Similar grain bill by weight, though it was all pilsner malt rather than with a few character malts like this one.

The crush of the grain is the most important factor in conversion efficiency. If you are relying on the LHBS to crush the grain you are paying twice for that service. First is the cost of the grain which will be cheaper in bulk than from the LHBS on a per recipe basis. Second is the lower efficiency that forces you to use more grain to get the same OG.

The thing that has frustrated me most has been the inconsistency from batch to batch, even when some of the grist bills are 80-90% identical. But you're right, the one variable I have no control over, especially now with Covid and our LHBS only doing curbside pickup, is the crush. Since my process and a majority of my grain bills don't differ significantly, it would make sense that this is where the "problem" lies. Maybe it is time for me to buy my own mill and buy sacks of Pilsner from the LHBS (no shipping cost).

...Unless you are trying to save money or your enjoyment of the hobby is a more technical pursuit, efficiency is not a measure of the brewer....
... If there are not many then maybe an assessment of why you moved to the new setup?

This is true. I put too much value on hitting numbers perfectly and maximizing efficiency--I'm not doing this professionally, so it's pretty inconsequential and more a source of stress on brewday than anything. The goal, first and foremost, is to create something that I love to drink and am proud to share. Nobody drinking my beer is going to say, "hmm, this tastes 4 points too low. How was your efficiency? What was your preboil SG?" LOL

I'm glad I went to the single-tier, pump driven setup and can brew indoors now. I never did brew on propane, but brewing via NG on the back deck at my old house (no garage or off-street parking) was something I wanted to get as far away from as possible when we moved. I had to break everything down after brew day and lock it in our shed across the swampy backyard, so I really just wanted a permanently installed, mostly CIP system to live in my garage. Another motivation was to be able to do accurate step mashes for the Belgians and German beers that I primarily brew. The driving force was never the ability to fly sparge. In my mind, I guess it just seemed like it would be a waste to continue batch sparging now that I have the equipment and means to fly sparge.

Maybe I'll buy a mill and try a simple 5% ABV Kolsch or something with a finer crush and use that to help dial in my efficiency. Since that's the big variable I can't yet control for (the crush), it makes sense to start there. At the end of the day, I really just want it to be consistent.

 

[stickyfinger]

i lost efficiency going to HERMS from a 5G cooler. i realized my new mash tun had a huge dead space. i got a spike kettle with lip around the bottom and tiny dead space and it helped a ton. also, i still get better efficiency or at least as good in batches that fill the mash tun more. so a bigger beer or a 12G batch might get similar or better efficiency than a 5G batch of 1.050 beer. must have to do with flow through the tun and the shorter grain bed being harder to spare efficiently. oh, one other thing that gave me a boost was using 1 lb of rice hills in every batch regardless of malt bill or batch size and letting the wort run out of my mash tun until the malt starts getting dry and thick on top then crank up the sparse water and keep it at an inch or so above the malt level.

 

[bracconiere]

i pull ~90% with a hybrid batch fly sparge....(actually just lazy fly sparge that goes dry a couple of times during the process, lol) just throwing a thought out.....


edit: and if you want to try it, before i started doing a second step at 162f for 30 min, i only got 83%...but i have no idea what that would do to fermentability, because i add gluco to everything....

 

[stickyfinger]

i get maybe 3-5% higher efficiency with a mash out step too. it makes for. higher OG and a higher FG unless the yeast is a STA1 beast

 

[TheMadKing]

On a recirculating HERMS system, I'll also add that your efficiency is massively affected by how evenly distributed your recirculation is through your grain.

If you are recirculating too fast you will get a compacted grain bed and channeling. It's best to recirculate as slow as possible will still being able to maintain the temperature you want. It's also important to start your pump with the flow valve closed and open it slowly to increase flow as needed. If you start with it wide open you get a compacted grain bed almost immediately.

On your next brew day. Shut off your recirc pump every 20 minutes and stir the mash for about a minute then restart your circulation. It's what I do on big beers to boost efficiency by maximizing the distribution of the grain in the wort and works well.

 

[madscientist451]

I'm currently brewing a Belgian style Tripel with a 25# grain bill (10.5 gallon batch, mostly pilsner malt) on my 15 gallon eHERMS system.

Assuming the roller settings at my LHBS hasn't changed, what in my process is causing such crummy numbers?

As low tech as batch sparging was, I'm thinking of going back to that method (on this system). Any thoughts from the forum wizards?

So you spent the cash to build 15 gallon eHERMS system and still rely on your LHBS for the crush?
A mill and a scale will add up to a small fraction of what you have spent on your brewing rig and you can recover that money when you start buying grain by the sack instead of paying retail.
Back to your original question, is fly sparging a waste of time? Yup, I'm going to say it is a waste of time.
I don't have much free time for brewing these days and when I get a day off, I'll do an overnight BIAB mash and then boil in the morning. I'm getting super high efficiency with just a bag and a pot.

 

[TheMadKing]

So you spent the cash to build 15 gallon eHERMS system and still rely on your LHBS for the crush?
A mill and a scale will add up to a small fraction of what you have spent on your brewing rig and you can recover that money when you start buying grain by the sack instead of paying retail.
Back to your original question, is fly sparging a waste of time? Yup, I'm going to say it is a waste of time.
I don't have much free time for brewing these days and when I get a day off, I'll do an overnight BIAB mash and then boil in the morning. I'm getting super high efficiency with just a bag and a pot.

There's no sense in talking down to a guy for not brewing the way you do. His priority is probably not minimum effort on brew day. He bought the system, so it isn't productive to tell him he's wasted a bunch of money when all he asked for was help dialing in his existing system.

I agree that a mill is a good investment to control your process, but the notion of "saving money" while brewing by buying grain in bulk is not a great argument IMO. If you save more than $200/year by buying bulk grain vs per recipe, I'll be amazed, and there's far more convenient ways to save $200/year.

I actually made the switch away from the simplicity of BIAB to a 15 gallon HERMS system and have no regrets. I now have about an hour longer brew day, but much more control over my process, the ability to change mash temps much more easily, more consistent beers, higher efficiency (Because I can do a better sparge than I could with BIAB). There are numerous advantages with a HERMS system, and one of the big drawbacks is loss of the simplicity of BIAB, but that doesn't make it a "waste of time" or a dumb way to brew.

My priority on brew day is not saving time and minimizing effort. It's enjoying the process, playing on my system, and being able up manipulate almost every parameter of my beer if I choose to.

 

[luckybeagle]

There's no sense in talking down to a guy for not brewing the way you do. His priority is probably not minimum effort on brew day. He bought the system, so it isn't productive to tell him he's wasted a bunch of money when all he asked for was help dialing in his existing system.

I agree that a mill is a good investment to control your process, but the notion of "saving money" while brewing by buying grain in bulk is not a great argument IMO. If you save more than $200/year by buying bulk grain vs per recipe, I'll be amazed, and there's far more convenient ways to save $200/year.

I actually made the switch away from the simplicity of BIAB to a 15 gallon HERMS system and have no regrets. I now have about an hour longer brew day, but much more control over my process, the ability to change mash temps much more easily, more consistent beers, higher efficiency (Because I can do a better sparge than I could with BIAB). There are numerous advantages with a HERMS system, and one of the big drawbacks is loss of the simplicity of BIAB, but that doesn't make it a "waste of time" or a dumb way to brew.

My priority on brew day is not saving time and minimizing effort. It's enjoying the process, playing on my system, and being able up manipulate almost every parameter of my beer if I choose to.

Thanks! I don't feel I wasted my money on the setup either, as I enjoy my much more orderly brew days in the garage. I got to a point where I was set up "enough" and shifted my focus on buying ingredients to brew as building the setup took about a month of accumulating parts, drilling kettles etc, during which point the taps ran completely dry. Once I could flip the system "on," I started buying ingredients and stopped buying equipment. I'm slightly embarrassed to say i use a cheap desk fan to blow steam away from my kettle rather than a vent hood, and that my power supply cable to the Auber Cube 2E controller is only 2ft long, forcing me to move my brew rig close to the outlet every brew day (I ran out of 10/3 wire!). There's always something needed.

If I had an unlimited budget, I would have a proper mill already. Especially now, I wish I didn't have to go to the LHBS every time I wanted to brew. Saving a little money would be nice, but with biweekly brewing I'm sure the cost recovery time would still be pretty long. I will probably pick one up with my next online order--when I finally buck up and get ventilation/longer power cable/etc.

You made a comment earlier about recirculating too fast. I've been running it full bore after giving it a good 5 minutes at a low flow for the grain bed to settle. I can definitely turn that down and still hold temperature, but how do you step up in a timely manner if you recirculate slowly?

 

[RM-MN]

If I had an unlimited budget, I would have a proper mill already. Especially now, I wish I didn't have to go to the LHBS every time I wanted to brew. Saving a little money would be nice, but with biweekly brewing I'm sure the cost recovery time would still be pretty long.

Can you afford an improper mill now? Corn Wheat Grinder Big Hopper Grain Grinder Manual Home Commercial - Walmart.com

 

[Bobby_M]

Do you have a diptube attached to the inside of the mash tun's drain? Are you keeping your sparge water above the grain level? Are you sparging slow enough? 1 quart per minute max.

Test your conversion efficiency next time you brew. That is, take a gravity reading at the end of the mash. A 10 minute ramp up of 10F at the end of the mash will work wonders. I also agree that stirring your mash about 5 minutes prior to the sparge will do well to avoid channeling. Just slowly recirculate a bit directly after to clear the wort up before switching over to the sparge/runoff step.

You are pushing your sparge through the HERMS coil right?

 

[bkboiler]

I feel ya....I just upgraded my system (almost complete) and stretched my budget to afford the best quality stuff I could...hate to say but if the stuff doesn't work out perfectly I'll have to save up to replace some of it...
I also went with a super low profile false bottom that was easy to clean to help with efficiency (reduce dead space) and give me more flexibility for smaller beers or smaller batches ...

 

[VikeMan]

Thanks! I don't feel I wasted my money on the setup either, as I enjoy my much more orderly brew days in the garage.

Whenever I see people arguing about a process or equipment being necessary vs overkill, it reminds me of the George Carlin bit about drivers...
"Anybody driving slower than you is an idiot. Anyone going faster than you is a maniac.”

 

[luckybeagle]

Can you afford an improper mill now? Corn Wheat Grinder Big Hopper Grain Grinder Manual Home Commercial - Walmart.com

Has anyone tried to hook up a drill to that one? Wondering if it's possible to replace the handcrank with something and connect a drill to it. Interested.

Do you have a diptube attached to the inside of the mash tun's drain? Are you keeping your sparge water above the grain level? Are you sparging slow enough? 1 quart per minute max.

Test your conversion efficiency next time you brew. That is, take a gravity reading at the end of the mash. A 10 minute ramp up of 10F at the end of the mash will work wonders. I also agree that stirring your mash about 5 minutes prior to the sparge will do well to avoid channeling. Just slowly recirculate a bit directly after to clear the wort up before switching over to the sparge/runoff step.

You are pushing your sparge through the HERMS coil right?

Hey Bobby, I do have a diptube attached to the inside of the mash tun. I have just under 2.5 gallons of "dead space" underneath the false bottom, but I recirculate the entire time so it doesn't seem like this should affect efficiency since the water is not just sitting there like it would in a cooler. It's right where the tri-ply bottom connects to the single ply sides of the kettle (you can see the lip in the pictures, not a great design IMO).

Yes, I do pass my sparge water through the herms coil on its way to the top of the grain bed during the sparge, and keep 2-3" of sparge water on top of the grain bed. I take about an hour to sparge 12 gallons of preboil volume (0.8 quarts per minute) and always do a mashout--I set my PID controller to 175 to hit around 170 in the MLT, and hold it for 10 minutes before rearranging the hoses for the sparge. Maybe I should raise this a bit higher? There is a significant lag time between the HLT temperature and the grain bed coming up to temp, so I'm not sure how long the grain is actually AT 170ish since the probe just measures the HLT-OUT temperature.

 

[stickyfinger]

i had a similar dead space before the Spike kettle upgrade. you lose efficiency but not sure it's worth an upgrade for the money. you really notice it on a small batch size in a large mash tun, like a 6 gallon batch in a 15G mash tun. I just hated constantly having lower sparging efficiency, and it was a bit bigger than my previous kettle. Plus, it had a crack where the weld met the bottom, so I had to upgrade. The issue with a big dead space is you have to have a higher dilution rate in the mash for the same amount of liquid/malt ratio above the false bottom. does that make sense?

The other thing that helped me was to let the wort level run down in the mash tun before starting the sparge. let the mash get thicker so it starts seeming dry on top almost and then fire up the sparge. that way you know you're not starting the sparge too soon and diluting the runoff at the top due to mixing of the sparge water with the concentrated wort at the top.

one thing you can do to test your mash compaction is to try a familiar batch and just throw in 1 lb of rice hulls. if your efficiency goes up you know your mash is too thick or compacted or whatever and the rice hulls are helping that. i just use a lb in every batch now as it completely prevents any thick mashes or sparging issues at all. you can recirc very fast, but i never run it wide open. seems like running it wide open would compact the mash, certainly without hulls.

 

[RM-MN]

Has anyone tried to hook up a drill to that one? Wondering if it's possible to replace the handcrank with something and connect a drill to it. Interested.

I did a little grinding to change the shaft where the handle attaches from a 3 lobe to 6, then fitted a socket to the shaft and put an adapter in my drill to do the cranking for me. It takes a decent drill to get enough torque but it sure speeds up the milling. The last I used the mill that way I used a cordless hammer drill that had a side handle and I needed that to hold the torque.

 

[Bassman2003]

I recently purchased this mill and am happy with it. It is a good value imho - Cereal Killer Grain Mill for Crushing Grains and Barley

 

[day_trippr]

Probably the best value in home-scale mills today...

Cheers!

 

[TheMadKing]

You made a comment earlier about recirculating too fast. I've been running it full bore after giving it a good 5 minutes at a low flow for the grain bed to settle. I can definitely turn that down and still hold temperature, but how do you step up in a timely manner if you recirculate slowly?

I suspect that's your main issue. If you are doing a step mash, turn up flow to full bore until you reach temp, then shut your flow off, stir your mash thoroughly, and then turn on the flow again to a slow trickle.

 

[philjohnwilliams]

Thanks! I don't feel I wasted my money on the setup either, as I enjoy my much more orderly brew days in the garage. I got to a point where I was set up "enough" and shifted my focus on buying ingredients to brew as building the setup took about a month of accumulating parts, drilling kettles etc, during which point the taps ran completely dry. Once I could flip the system "on," I started buying ingredients and stopped buying equipment. I'm slightly embarrassed to say i use a cheap desk fan to blow steam away from my kettle rather than a vent hood, and that my power supply cable to the Auber Cube 2E controller is only 2ft long, forcing me to move my brew rig close to the outlet every brew day (I ran out of 10/3 wire!). There's always something needed.

View attachment 678632

If I had an unlimited budget, I would have a proper mill already. Especially now, I wish I didn't have to go to the LHBS every time I wanted to brew. Saving a little money would be nice, but with biweekly brewing I'm sure the cost recovery time would still be pretty long.

When I combine the cost savings of buying grain in bulk and using a little less grain due to better control of my crush, and thus my efficiency, I calculated that my mill paid for itself after 22 batches of beer. If you are brewing biweekly then a cereal killer type mill can pay for itself in about a year.

 

[RM-MN]

When I combine the cost savings of buying grain in bulk and using a little less grain due to better control of my crush, and thus my efficiency, I calculated that my mill paid for itself after 22 batches of beer. If you are brewing biweekly then a cereal killer type mill can pay for itself in about a year.

I think my Corona mill paid for itself on the first batch.

 

[madscientist451]

If I had an unlimited budget, I would have a proper mill already. Especially now, I wish I didn't have to go to the LHBS every time I wanted to brew. Saving a little money would be nice, but with biweekly brewing I'm sure the cost recovery time would still be pretty long.

I don't have a proper mill, its a Barley Crusher Malt Mill with 2 rollers and the hopper isn't very large. But I run the grain through twice and it works fine.
I think they are like $150 these days. I buy used food grade buckets from a local bakery for $1 and that's my grain storage.
The money saved on grain can pay for the mill, but that's not the best reason for having one. You have more control when you do your own milling. Also, when you build up a selection of grains you can brew what you want when you want. My LHBS is OK, but often they are out of something I want and a trip there adds about 2 hours to my commute home after work.
The original question asked if fly sparging is a waste of time. I still say it is a waste of time, you just don't need to do it to make good beer. For me, going to my LHBS (even though I'd like to support them) is another waste of time.
I waste time in other ways, of course, usually by drinking something I've made.

 

[TheMadKing]

The original question asked if fly sparging is a waste of time. I still say it is a waste of time, you just don't need to do it to make good beer. For me, going to my LHBS (even though I'd like to support them) is another waste of time.
I waste time in other ways, of course, usually by drinking something I've made.

I would argue that fly sparging is the best balance between saving time and boosting efficiency (saving a few cents on your grain).

Batch sparging is the best way to get maximum efficiency, but it can be time consuming depending on how long you let each sparge rest.

If you're not sparging at all, your efficiency is always worse than if you sparge.

A quick-ish (30 minute) fly sparge gives you an appreciable efficiency boost, and you can have your wort runoff heating during the fly sparge, so it doesn't add much time to your overall brew day really.

Again it just depends on your priorities. I like being efficient with my grain, but as long as I'm above 75% I'm happy. My priority on brew day is to enjoy the day and hit my numbers, fly sparging helps me do that. You absolutely don't need to do it to make good beer, but its one perfectly acceptable method that's used by professionals all over the world.

I just checked my LHBS prices and he charges $51 for a 50lb bag of 2 Row ($1.02/lb) and if you buy it by the pound it's $1.65. So you save $.63/lb. An average batch of beer using 8lb of base malt saves you $5.04. So if you brew 20 batches (the legal limit for a single person in a year.. Not that anyone observes this) you save $100.80 in a year. If you brew 40 batches, which is the legal limit for a married couple you save $201.40 per year.

If you order a cheap Starbucks/Dunkin/whatever Coffee (Americano or drip) once or twice a week for a year at $3.50 then you could have saved it there.

If you go out to dinner and drinks and spend $50 (a cheap date in my household) more than 4 times per year then you could have saved it there.

My point is that buying in bulk DOES save money, but its not enough that it enters the equation for me. The difference in efficiency between sparging and not sparging is about $1.65 in grain, but I get pretty irritated on brew day if my BH efficiency is only 60% and I miss all my numbers, so saving myself from irritation and maximizing enjoyment on brew day is priceless

 

[RM-MN]

Batch sparging is the best way to get maximum efficiency, but it can be time consuming depending on how long you let each sparge rest.

There is no reason to let a sparge rest. The sugars are already there ready to be rinsed from the grains. Dump the water in, give it a good stir, then drain.

 

[VikeMan]

^ This is true. Fly sparging's efficiency benefits from slow runoff, because that (to an extent) pushes out wort and replaces it with water. In batch sparging, you could let it sit forever without changing concentrations any further.

 

[TheMadKing]

There is no reason to let a sparge rest. The sugars are already there ready to be rinsed from the grains. Dump the water in, give it a good stir, then drain.

Soak a sponge in salt water

Then dip it in clean water quickly, soak it in the salt water again then dip it in a second bowl of clean water and let it sit for 5 minutes. Taste both bowls of clean water.

Which one extracted more salt?

There is a contact time factor to allow the new concentration to equilibrate in the liquid solution and the grain particles - I don't know what the correct amount of time is, but a few minutes 5-10 seems reasonable, but there would logically be a point of no-gain where equilibrium is reached. I would be very surprised if that happens completely within 2 minutes (the amount of time it takes to stir and run off)

 

[wilserbrewer]

While I agree, it does seem intuitive that it would take some amount of time for the sugar to equilibrate from the grain to sparge water during a batch sparge, however Denny Conn, a well respected pioneer of the batch sparge process found that the time to equilibrate was about the time it takes for a “good” stir, whatever that is.

I believe Denny claims to have tried it both ways and found little to no difference, and therefore a rest is not required according to him.

Perhaps the grain particles being so small, the sugar is rinsed rather quickly.

The sponge example should perhaps include squeezing the sponge a few times to replicate the action of a “good stir” lol jk

 

[doug293cz]

Soak a sponge in salt water

Then dip it in clean water quickly, soak it in the salt water again then dip it in a second bowl of clean water and let it sit for 5 minutes. Taste both bowls of clean water.

Which one extracted more salt?

There is a contact time factor to allow the new concentration to equilibrate in the liquid solution and the grain particles - I don't know what the correct amount of time is, but a few minutes 5-10 seems reasonable, but there would logically be a point of no-gain where equilibrium is reached. I would be very surprised if that happens completely within 2 minutes (the amount of time it takes to stir and run off)

While I agree, it does seem intuitive that it would take some amount of time for the sugar to equilibrate from the grain to sparge water during a batch sparge, however Denny Conn, a well respected pioneer of the batch sparge process found that the time to equilibrate was about the time it takes for a “good” stir, whatever that is.

I believe Denny claims to have tried it both ways and found little to no difference, and therefore a rest is not required according to him.

Perhaps the grain particles being so small, the sugar is rinsed rather quickly.

The sponge example should perhaps include squeezing the sponge a few times to replicate the action of a “good stir” lol jk

Wilser is correct. The sponge alone is a bad model for a stirred batch sparge. Holding the sponge in clean water and squeezing it several times, is a better analogy for stirring.

The goal in a batch sparge is to homogenize the extract (sugar) concentration throughout the entire volume, prior to running off. Stirring can accomplish this in a short period of time. Without stirring, you are depending on diffusion to homogenize the wort, which will take a significantly longer period of time.

There is a situation where a dwell after adding the sparge water can improve efficiency. This happens when the conversion is not complete at the end of the initial mash, and no mashout is done. In this case, conversion can continue during a sparge dwell, resulting in an increase in the conversion efficiency component of mash efficiency. However, getting complete conversion prior to initial run-off will still result in better mash efficiency.

Brew on

 

[luckybeagle]

Really enjoying this discussion; thanks everyone for contributing thus far.

 

[TheMadKing]

Wilser is correct. The sponge alone is a bad model for a stirred batch sparge. Holding the sponge in clean water and squeezing it several times, is a better analogy for stirring.

The goal in a batch sparge is to homogenize the extract (sugar) concentration throughout the entire volume, prior to running off. Stirring can accomplish this in a short period of time. Without stirring, you are depending on diffusion to homogenize the wort, which will take a significantly longer period of time.

There is a situation where a dwell after adding the sparge water can improve efficiency. This happens when the conversion is not complete at the end of the initial mash, and no mashout is done. In this case, conversion can continue during a sparge dwell, resulting in an increase in the conversion efficiency component of mash efficiency. However, getting complete conversion prior to initial run-off will still result in better mash efficiency.

Brew on

Consider me very surprised and corrected

I would have expected that even with stirring, there would still be some time needed to equilibrate the solution

Another factor that you've not mentioned and that I missed, is that batch sparging is typically done successively. So even if there is a time factor involved, it's reduced by the fact that clean water is added a second and even third time in some cases.

the analogy then becomes

Dip the sponge in clean water and then dip it in clean water again immediately, which one has more salt

 

[doug293cz]

Consider me very surprised and corrected

I would have expected that even with stirring, there would still be some time needed to equilibrate the solution

Another factor that you've not mentioned and that I missed, is that batch sparging is typically done successively. So even if there is a time factor involved, it's reduced by the fact that clean water is added a second and even third time in some cases.

the analogy then becomes

Dip the sponge in clean water and then dip it in clean water again immediately, which one has more salt

I believe most brewers who use a batch sparge, do a single batch sparge. There are some who do a double batch sparge. There may even be some who routinely do a triple batch sparge, but they are a small minority of batch spargers. Each successive batch sparge recovers a little more extract (sugar) from the grain bed, but each additional sparge has less benefit than the previous. This is all laid out in the chart in the 2nd post in this thread. The chart assumes that the wort has been homogenized prior to each run-off.

Typical procedure for batch sparging is to:

1. Run off wort
2. Add sparge water to MLT
3. Stir sparge water and grain
4. Run off wort
5. repeat from step 2 as desired

If the stir in step three is adequate, then the desire for homogenized wort will be met.

So, your: "Dip the sponge in clean water and then dip it in clean water again immediately, which one has more salt" should become: "Dip the sponge in clean water, then squeeze multiple times, transfer the sponge to clean water, then squeeze multiple times. Which of the two originally clean water masses has more solute (sugar, salt, whatever)?" The answer is the first water that the sponge was dipped and squeezed in has more solute.

Brew on

 

[luckybeagle]

Whenever I would batch sparge in my igloo cooler for large, high gravity batches, I had no choice but to double or triple batch sparge--I simply did not have the space to sparge with the amount of water needed to reach preboil volume. I remember these making for long brewdays, but IIRC I was still hitting 75% efficiency or greater on those high OG batches. This is what I would achieve on normal gravity batches employing a single batch sparge, so I'm of the mindset that a double sparge results in slightly better efficiency given the tendency for higher grain bills to result in lower numbers (I probably should've been hitting 65 or 70%). This was with a braided stainless line in the bottom of the tun and not a legit false bottom.

For my process, I usually dumped in the sparge water (which was hot, about 190F--at least for the first sparge) fairly aggressively from the kettle and let that mix up the grains, then immediately began vorlaufing/recirculating with the help of a pump. I moved away from letting the grain sit and settle once I got the pump. I don't recall my efficiency improving or reducing, but that's just one anecdote. I also stopped letting the grain sit based on Denny's writings.

 

[VikeMan]

so I'm of the mindset that a double sparge results in slightly better efficiency given the tendency for higher grain bills to result in lower numbers (I probably should've been hitting 65 or 70%).

Yep. Double batch sparging ("all other things being equal") yields higher mash efficiency than single. And that tendency for larger grain bills to result in lower efficiency (given same sparge method) is quite simple (ok, at least not rocket science) to calculate. I've seen a lot of folks say things like "I get 80% mash efficiency with most of my beers, but only 70% with high gravity beers," as if it's something binary. But if they were to plot their mash efficiencies vs. grain bill size, they'd find a pretty smooth curve.

 

[luckybeagle]

Yep. Double batch sparging ("all other things being equal") yields higher mash efficiency than single. And that tendency for larger grain bills to result in lower efficiency (given same sparge method) is quite simple (ok, at least not rocket science) to calculate. I've seen a lot of folks say things like "I get 80% mash efficiency with most of my beers, but only 70% with high gravity beers," as if it's something binary. But if they were to plot their mash efficiencies vs. grain bill size, they'd find a pretty smooth curve.

Agree completely on it being linear. There's no way the mash tun *knows* to hit 75% efficiency at 15 lbs, and then arbitrarily decides to drop to 65% at 16 lbs.

 

[doug293cz]

Yep. Double batch sparging ("all other things being equal") yields higher mash efficiency than single. And that tendency for larger grain bills to result in lower efficiency (given same sparge method) is quite simple (ok, at least not rocket science) to calculate. I've seen a lot of folks say things like "I get 80% mash efficiency with most of my beers, but only 70% with high gravity beers," as if it's something binary. But if they were to plot their mash efficiencies vs. grain bill size, they'd find a pretty smooth curve.

See post #2 in this thread

Agree completely on it being linear. There's no way the mash tun *knows* to hit 75% efficiency at 15 lbs, and then arbitrarily decides to drop to 65% at 16 lbs.

Not quite linear, but definitely monotonically decreasing with increasing grain bill size. Again, see post #2 this thread.

Brew on

 

[VikeMan]

See post #2 in this thread

Lol. I guess someone besides me has plotted this stuff. I should have read the whole thread! The calculations I've done were in the context of predicting changes in mash efficiency when changing grain bill size and/or sparge methods, given particular (user) brew house setups (mash tun dead space, etc), i.e. constant volume wort losses.