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Does recirc replace sparge?

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kohalajohn

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I did a full volume mash and the efficiency was acceptable to me, at least compared to a quick pour over. Not compared to a full fly of course, but that's ok.

I only did it by mistake. I come from the old days when you absolutely had to sparge. That's why we all had 3V. If you had told me that AIO would be acceptable I would not have believed it.

Anyway, I was following a Brewfather recipe. I added the required water, thinking there was some left for sparge in my brewzila. Then realized that damn, I now have a full volume mash. Damn.

But to my surprise, when I pulled it the OG was ok and it make an excellent English Pale Ale. With no sparge. Sorcery!

Maybe it's the recirc? Does an hour of recirc (or vorlauf) pull so much sugar away from the tiny particles of grist and husk that most of the work of sparging is already done by the time the mash is completed?

In other words is modern recirc actually the sparge itself?
 
Technically, no. But there are many ways to reach your pre-boil entire volume, with just as many trade offs as there are techniques.

It sounds like you're happy with your new technique. Frankly, I'd ignore everyone's advice and just roll with it until you find a compelling reason to reappraise this technique that seems to be working for you.
 
This seems to be the week where this experiment I did a while back is relevant. This is from a review I did using an Anvil Foundry 6.5 gallon brew unit. In summary, full volume no recirc and full volume with recirc were essentially the same. Sparge added a big uptick in mash efficiency.

-------------------

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.
 
I did a full volume mash and the efficiency was acceptable to me, at least compared to a quick pour over. Not compared to a full fly of course, but that's ok.

I only did it by mistake. I come from the old days when you absolutely had to sparge. That's why we all had 3V. If you had told me that AIO would be acceptable I would not have believed it.

Anyway, I was following a Brewfather recipe. I added the required water, thinking there was some left for sparge in my brewzila. Then realized that damn, I now have a full volume mash. Damn.

But to my surprise, when I pulled it the OG was ok and it make an excellent English Pale Ale. With no sparge. Sorcery!

Maybe it's the recirc? Does an hour of recirc (or vorlauf) pull so much sugar away from the tiny particles of grist and husk that most of the work of sparging is already done by the time the mash is completed?

In other words is modern recirc actually the sparge itself?

It's almost like a lot of experienced brewers keep telling you that full volume mashing is easy and works really well and it turns out they were right? Amazing.

Other than tradition and commercial bottom lines driving maximum extraction, there is no mystery to why this works.

Grain has X potential extract and the gravity of wort that it can make is X divided by volume. The reason everyone is conditioned to think they have to sparge is that a concentrated mash is a LOT of sugar with a LITTLE liquid volume so the gravity of that mash gets "HIGH". When that is drained away, all the wort that sticks to the grain particles has LOT of sugar in it. Sparging grabbed that sugar and drained it away. In the end, you have a kettle that is about half really high gravity wort and half low gravity wort (what came from the sparge).

Ok, now how Full Volume, No Sparge works. Now you have that same potential sugar because it's the same grain bill as above. However, instead of the mash wort being really high gravity, the whole thing is MEDIUM gravity because it's diluted more. When you drain the wort away, the wort stuck to the grain particles is lower and it's not a huge deal to leave it there and throw it out with the grain.


No, recirculating is not performing any kind of sparge. The primary function of the recirculation is to distribute heat from where it's being input to the system across the entire mash (such as to the top where the heat loss is the greatest). It's also providing a clarifying function similar to the VORLAUF in a sparged system.
 
That's the first explanation I have heard, that really makes sense.

By taking out six liters for a later sparge, you are causing the mash wort to be concentrated with sugar. So then you HAVE to wash those concentrated sugars off the husks.

The sparge is only solving the problem that it created in the first place.

And yeah, ok, a sparge will wash out a bit more sugar than will a full volume. But I don't think it's a lot.

And anyway my spent grains compost, so next year that nutrition will be tomatoes, so nothing is really lost.
 
......
By taking out six liters for a later sparge, you are causing the mash wort to be concentrated with sugar. So then you HAVE to wash those concentrated sugars off the husks.
.....
A quick sparge, can wash those sugars off the surfaces. But will free little of the sugars still within the grain.

At the end of mashing, sugar concentrations in the wort, and in water inside the grain, will be fairly similar. You know from the grain absorbtion ratio, what fraction is absorbed.
The stiffer the mash, the higher the percentage of strike water is absorbed, and the higher the percentage of sugars will remain in the grain after draining.

A stiff mash, needs a long slow sparge, that gives trapped sugars time to diffuse out. A floating sparge might be the best bet.

I'm using a thin mash (75% water), and quick sparge (25%). But might try switching to 80:20.
 
That's the first explanation I have heard, that really makes sense.

By taking out six liters for a later sparge, you are causing the mash wort to be concentrated with sugar. So then you HAVE to wash those concentrated sugars off the husks.

The sparge is only solving the problem that it created in the first place.

And yeah, ok, a sparge will wash out a bit more sugar than will a full volume. But I don't think it's a lot.

And anyway my spent grains compost, so next year that nutrition will be tomatoes, so nothing is really lost.
Big shout out to Bobby and his excellent explanation. I had pretty much stopped sparging a few years ago after experiencing exactly the same thing with my Braumeister AIO that I've been brewing with for over 12 years. BeerSmith was calculating my mash efficiencies (7.0 gallon mash = 1.5 gallon sparge) consistently at 82% +/- 2 points, and I was pretty satisfied with the results. Then one brew day I decided to try no-sparge and got the same results, 8.5 gallon full volume mash. Now about the only time I do a sparge brew session is when my grist bill is over 14# and I have to over-stuff the malt pipe to get all the grains inside. The efficiency drops, and sparging will get me back up to my predicted numbers.

Two caveats: I almost always perform a Hoch-Kurz step mash with :20 minutes mash out. The second caveat is the basic flow pattern of recirculation in the Braumeister design which flows from the bottom up through the grain bed against gravity flow. Occasionally this can result in limited "fountaining" of wort to the top plate. But because of the upward flow which tends to float the grain, the channeling and fountains quickly resolve themselves without having to stop the flow, remove the top plate and stir the grain bed. The system is like a continuous Vorlauf from the beginning of mash through the final moment of mash-out. There isn't much sugar left to be 'washed' from the grist after an hour+ of recirculation.
 
A quick sparge, can wash those sugars off the surfaces. But will free little of the sugars still within the grain.

At the end of mashing, sugar concentrations in the wort, and in water inside the grain, will be fairly similar. You know from the grain absorbtion ratio, what fraction is absorbed.
The stiffer the mash, the higher the percentage of strike water is absorbed, and the higher the percentage of sugars will remain in the grain after draining.

A stiff mash, needs a long slow sparge, that gives trapped sugars time to diffuse out. A floating sparge might be the best bet.

I'm using a thin mash (75% water), and quick sparge (25%). But might try switching to 80:20.

Sparge time required to maximize efficiency depends on the sparge process. If doing a fly sparge (continuous sparge concurrent with wort run-off) then sparging slowly to allow for diffusional mixing, and preventing channeling, is important. But if batch sparging, then you can minimize the time required by aggressively stirring the sparge water and grain, so that you don't have to depend on diffusion to homogenize all of the wort. With batch sparging you can drain quickly, add sparge water, stir aggressively for a few minutes, and then drain quickly again - no need to spend time waiting for diffusion.

To maximize lauter efficiency when batch sparging, you want the initial run-off volume to equal the sparge run-off volume. This can be demonstrated mathematically. The change in efficiency going from a run-off ratio of 60:40 to 40:60 is less than 0.5%, which is less than the uncertainty in efficiency calculations. The change in efficiency going from run-off ratio of 70:30 to 30:70 is only a little over 1%. The chart below is from Braukaiser (no-longer available on the web.)

Lauter Eff vs Run-off ratio Kaiser.png


A simple rule-of-thumb that will keep you within the 60:40 to 40:60 run off ratio for almost any grain bill size is to mash with 60% of your required water, and sparge with the remaining 40% of the water, when batch sparging.

With fly/continuous sparging you maximize lauter efficiency by mashing as thick as your system allows, and then sparging with as much water as it takes to achieve your target pre-boil volume.

Fly Sparge Eff vs Grain to Pre-boil Ratio.png


I really wish you would quit using the term "floating sparge" and stick with the generally accepted terminology of "fly" or "continuous" sparging. You are the only writer I have seen using this terminology, and using terms that you like, but are not familiar to others, does not help you communicate with others. We don't need to build a "Tower of Babble".

Brew on :mug:
 
There isn't much sugar left to be 'washed' from the grist after an hour+ of recirculation.

Recirculation does nothing to help you get more sugar out of the mash than not recirculating. It helps with temperature stability, and may increase your conversion rate by a small amount. But if you mash long enough to get 100% conversion, there is no efficiency difference with recirc vs. not recirculating.

Sparging vs. not sparging does make a significant difference in lauter efficiency, all else being equal. But, if all else is not equal, say squeezing the bag with no-sparge to reduce grain absorption, but not squeezing with batch sparge, then you may or may not get better lauter efficiency when sparging. The following chart shows this for batch sparging.

Efficiency vs Grain to Pre-Boil Ratio for Various Sparge Counts.png


Brew on :mug:
 
My brew day last week, I did a double bratch. The first, was fly sparge. The second was my first time doing full volume (with recir). Only lost a little over 10% on the efficiency, but was hoping to pick up some time, since a double brew day can get long. Took me 25-minutes to bring to a boil, which is about what it takes to fly sparge and bring to a boil on my system. I'm still propane, so probably not as efficient as an electric system trying to bring 7-8 gallons of 170 wort to a boil. Anyway, fly sparge and full volume recir definitely not the same. Although, the wort into the BK was sparkling clear under either method.
 

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Doug,
A main insight for me, is that remaining sugars are inside the grits, not resting on the surface.

I had imagined that after lifting the pipe, the sugars dissolved in the wort would fall into the boiler, while the sugars stuck to the outside of the grits would remain stuck there. And that's what sparging was for. It's just rinsing sugars off surfaces, so why bother with slow fly sparging? Just do a quick pour over and you're flushed the sugars off the sides of the grits. Just like washing PDW off the sides of the metal pipe, right?

But no. It's the dissolved sugars inside the grits that we are after. And after a mash it's all homogenous. A thick mash would have a high concentration of sugar both in the wort and in the grits. And the same concentration in both. Nature insists on equilibrium A thin mash would have low concentration in both, again equilibrium.

So yes, my quick cold water pour-over would flush a bit of sugar off the surfaces, but that's minimal. I'm not changing the concentration state, or equilibrium state, of the liquid dissolved in the grits. Only a long fly sparge does that.

I see now that a long fly sparge is like partigyle. You remove the first runnings of wort, then add fresh water to the grain and give it time for the dissolved sugars in the grits to achieve equilibrium with the low sugar volume in the outside liquid. That would draw out sugars from the grits, something that a pour-over could not do.

My choice recently is to leave it for the composer to turn into tomatoes. Picture below.




1751387035198.png
 
A main insight for me, is that remaining sugars are inside the grits, not resting on the surface.
Actually, it is most likely a combination of both. Wort likes to cling to surfaces (unless the surface is hydrophobic), so will cling to external, as well as internal surfaces (pore walls.) I've not been able to find any information on what the structure of spent grits looks like, so have no idea how much porosity they have, and the level of porosity, and pore size distribution, will determine the total pore volume, and how much surface area the pore walls have. These are the things that will determine how much wort is held inside of the grits. But definitely a large fraction of the retained wort will be on the outer surfaces of the grits, and in the open volume between the grits, which behave just like pores internal to the grits.

No matter where the retained wort actually resides, the important thing for an effective sparge is to homogenize the retained initial wort with the sparge water, so that the wort retained after the sparge is as dilute as possible.

Brew on :mug:
 
Ok, so we think of the grits as a number of small sponges.

Say there are, in a thick mash, ten parts of sugar per thousand, some residing inside the sponges, some on their outside, and some floating free. There is homogeneous distribution.

Remove the wort and the sponge content at ten parts per, remains behind. That's a lot of waste. You want to soak those sponges in fresh water to dilute the sponge content down to say two parts. Then when you've removed that wort, the sugars left behind in the sponges are a small amount, only two parts.

In a full volume mash, three parts per thousand are evenly distributed, also in the wort, and also in the sponges. Not ten parts.

Remove this wort and the sponge content at three parts per, remains behind. This is a small amount of waste.

Sound right?
 
This is supported by the experience of a member here who recently did a partigyle. He thought his second runnings would make a light beer. But they did not. He found it was extremely watery. Too thin to make anything resembling beer.

Which supports what Bobbi M has been saying, that as long as your conversion is good, the sugars left behind in those sponges, is a small amount.

I mean, sparge for it if you want. Sparging is part of the fun.
 
Ok, so we think of the grits as a number of small sponges.

Say there are, in a thick mash, ten parts of sugar per thousand, some residing inside the sponges, some on their outside, and some floating free. There is homogeneous distribution.

Remove the wort and the sponge content at ten parts per, remains behind. That's a lot of waste. You want to soak those sponges in fresh water to dilute the sponge content down to say two parts. Then when you've removed that wort, the sugars left behind in the sponges are a small amount, only two parts.

In a full volume mash, three parts per thousand are evenly distributed, also in the wort, and also in the sponges. Not ten parts.

Remove this wort and the sponge content at three parts per, remains behind. This is a small amount of waste.

Sound right?
Close enough. Even if the spent grits were solid, with no internal porosity (and thus no wort held inside the grit) the collection of grits would still act like a sponge, and retain wort. From an adsorption science perspective, there is no difference in behavior between internal pores, and empty space between particles.

Brew on :mug:
 
Sorry...not making light, but I never thought about the porosity of spent grains before. You add value to my reading with your apparent dissatisfaction with simply 'following instructions' and an unquenchable desire to actually understand every detail of whatever process you've chosen to engage in. A trait I suspect we share, but with brain damage, I have to get my joy vicariously from your brewing journey and ever-deeper questions so: Thank You! The best I could think of is capillary action as it was discovered some time ago that sparge-water needn't be hot, but unclaimed sugar remains nonetheless, there for the taking with a simple rinse at any temp. ...now I find myself wondering at the porosity of freshly mashed grains. ...which makes nice cookies BTW, if you don't mind the husks but hey; keeps your teeth clean.
:mug:
 
but everyone goes along with "grits" without issue?
Not everyone! The term is "grist"

Merriam-Webster
grist [noun]
a : grain or a batch of grain for grinding
b : the product obtained from a grist of grain including the flour or meal and the grain offals
 
Not everyone! The term is "grist"

Merriam-Webster
grist [noun]
a : grain or a batch of grain for grinding
b : the product obtained from a grist of grain including the flour or meal and the grain offals

Doesn't seem like "grist" implies the individual particles. That's what I am trying to convey with "grits." Grit is used in other industries for crushed particles.

Brew on :mug:
 
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grist [noun]
a : grain or a batch of grain for grinding
b : the product obtained from a grist of grain including the flour or meal and the grain offals
OTOH, this has always kind of stuck in my craw a little - why do we use the same word for the stuff we're going to grind and the stuff we already ground?
 
Sorry...not making light, but I never thought about the porosity of spent grains before. You add value to my reading with your apparent dissatisfaction with simply 'following instructions' and an unquenchable desire to actually understand every detail of whatever process you've chosen to engage in. A trait I suspect we share, but with brain damage, I have to get my joy vicariously from your brewing journey and ever-deeper questions so: Thank You! The best I could think of is capillary action as it was discovered some time ago that sparge-water needn't be hot, but unclaimed sugar remains nonetheless, there for the taking with a simple rinse at any temp. ...now I find myself wondering at the porosity of freshly mashed grains. ...which makes nice cookies BTW, if you don't mind the husks but hey; keeps your teeth clean.
:mug:
I enjoy your light hearted energy BC

Although I’m serious about quantum entanglement. It always happens at the worst time. And usually down in the bottom plate.
 
Sparge time required to maximize efficiency depends on the sparge process. If doing a fly sparge (continuous sparge concurrent with wort run-off) then sparging slowly to allow for diffusional mixing, and preventing channeling, is important. But if batch sparging, then you can minimize the time required by aggressively stirring the sparge water and grain, so that you don't have to depend on diffusion to homogenize all of the wort. With batch sparging you can drain quickly, add sparge water, stir aggressively for a few minutes, and then drain quickly again - no need to spend time waiting for diffusion.

To maximize lauter efficiency when batch sparging, you want the initial run-off volume to equal the sparge run-off volume. This can be demonstrated mathematically. The change in efficiency going from a run-off ratio of 60:40 to 40:60 is less than 0.5%, which is less than the uncertainty in efficiency calculations. The change in efficiency going from run-off ratio of 70:30 to 30:70 is only a little over 1%. The chart below is from Braukaiser (no-longer available on the web.)

View attachment 878912

A simple rule-of-thumb that will keep you within the 60:40 to 40:60 run off ratio for almost any grain bill size is to mash with 60% of your required water, and sparge with the remaining 40% of the water, when batch sparging.

With fly/continuous sparging you maximize lauter efficiency by mashing as thick as your system allows, and then sparging with as much water as it takes to achieve your target pre-boil volume.

View attachment 878913

I really wish you would quit using the term "floating sparge" and stick with the generally accepted terminology of "fly" or "continuous" sparging. You are the only writer I have seen using this terminology, and using terms that you like, but are not familiar to others, does not help you communicate with others. We don't need to build a "Tower of Babble".

Brew on :mug:
If you look at brewfather equipment profiles, the system efficiencies listed, are nearly all between 60% and 80%. Clearly where there's a 20% to 40% loss, it might be worth improving overall efficiency.

You say "with fly/continuous sparging you maximize lauter efficiency by mashing as thick as your system allows".
The lauter efficiency with any type of sparge, not just fly/continuous, will obviously increase with mash thickness, where there's higher sugar levels to start with.

After a very thick mash, you could get great lauter efficiency, but very poor overall efficiency. So I don't see why anyone would want to concentrate on simply maximising just lauter efficiency. Such as by using a 60:40 water ratio if batch sparging.

You say we shouldnt talk about a 'floating sparge' but only a 'fly/continuous' sparge.
But a floating sparge, where the drain is shut, maybe for a few hours, just after the last of the sparge water has been added. Is NOT a continuous sparge.

A long floating sparge has the potential to improve on the traditional 20-40% overall loss, by allowing sugars to diffuse from within the grain.
I guess those with shares in the grain supply chain, wouldn't want people talking about improving efficiency.
 
But a floating sparge, where the drain is shut, maybe for a few hours, just after the last of the sparge water has been added. Is NOT a continuous sparge.
Once you shut the drain it's a batch sparge. So maybe what you're trying to describe is a bit of a fly sparge followed by a bit of a batch sparge?
 
Actually, it is most likely a combination of both. Wort likes to cling to surfaces (unless the surface is hydrophobic), so will cling to external, as well as internal surfaces (pore walls.) I've not been able to find any information on what the structure of spent grits looks like, so have no idea how much porosity they have, and the level of porosity, and pore size distribution, will determine the total pore volume, and how much surface area the pore walls have. These are the things that will determine how much wort is held inside of the grits. But definitely a large fraction of the retained wort will be on the outer surfaces of the grits, and in the open volume between the grits, which behave just like pores internal to the grits.

No matter where the retained wort actually resides, the important thing for an effective sparge is to homogenize the retained initial wort with the sparge water, so that the wort retained after the sparge is as dilute as possible.

Brew on :mug:
The grain absorption ratio, tells us how much water is lost to the grain. But not the ratio between liquid trapped between surfaces, and inside.
An experiment might be to weigh say ten grains; soak them for hours; pat dry; re-weigh. Uncrushed grains would be best. That would give the internal absorbtion ratio.

An alternative experiment, would be to take say 100g of crushed grain, cover with water (maybe with a drop of detergant, to reduce surface tension and wet surfaces) then briefly shake, then drain through a fine sive.
Weigh to find water trapped, mostly on surfaces.
Some water might have been absorbed into fine particles (inc flour). But that's actually a good indicator of 'surface liquid' amount. Where sugars would likely be removed during a quick sparge.
 
The lauter efficiency with any type of sparge, not just fly/continuous, will obviously increase with mash thickness, where there's higher sugar levels to start with.

After a very thick mash, you could get great lauter efficiency, but very poor overall efficiency. So I don't see why anyone would want to concentrate on simply maximising just lauter efficiency. Such as by using a 60:40 water ratio if batch sparging.

There's no polite way to say this, but you don't know what you are talking about. It can be proven that the maximum lauter efficiency for a single batch sparge is when the run-off volume ratio is 50:50. Multiple people have done this analysis and come to the same conclusion. Do you know how to do a mass balance? That's what you need in order to track the mass of sugar collected by different process scenarios.

Mash efficiency is equal to conversion efficiency (percentage of starch converted to sugar in the mash) times lauter efficiency (percent of sugar actually created that makes it into the BK), and the two are almost completely independent of each other. If you have good lauter efficiency but bad mash efficiency, then your problem is inadequate conversion during the mash. The most common cause of low conversion efficiency is a mash time that is too short for gelatinization and hydrolysis to complete for the crush coarseness used. Fixes are to crush finer (if your system will tolerate it) or mash longer.

Brew on :mug:
 
pieces-parts?
chunklets?
bits?

"grain bits" --> contracted to "grits"

I didn't start using this term on my own, but followed the lead of others. But, if there is a better short word that can be used rather than typing out "grain particles" every time, I would love to hear about it.

Not a fan of "grist" when trying to make it clear that I am talking about crushed grain particles vs. the general grain bill or mass of crushed grain.

Brew on :mug:
 
But a floating sparge, where the drain is shut, maybe for a few hours, just after the last of the sparge water has been added. Is NOT a continuous sparge.
In brewing (and distilling) there's no such term used as a "floating sparge."
You're referring to what's known as a "batch sparge."

A batch sparge is performed by adding an amount of water to the grist after completely lautering (draining) the wort from the mash. After adding the water the grist is then stirred well in an effort to dissolve/extract the maximum amount of sugar. Then it's lautered as usual, and added to the wort previously collected.

Many brewers will do a double batch sparge, by fully draining the sparged grist before adding the second batch of sparge water. This is especially useful with higher gravity wort or thick mashes.
 
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"grain bits" --> contracted to "grits"
Being from the American deep South, the term "grits" has an indelible breakfast connotation.

When I was a kid, school children were let out for a week long holiday in early to mid Oct at grit harvest time. We would gather in large groups and visit farms where we would pick grits in friendly competition and sing traditional grit picking shanties. The grit bushes were low and with our keen eyesight and small fingers, we made quick work of collecting the pods. There were prizes for the first full bushels. Usually socks and slingshots and corncob dolls. Afterward, there was iced tea and lemonade and blackberry cobbler and the crowning of the Grit Queen and King.
 

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