Which is the more efficient Mashing/Sparge Technique?

[corypedia]

I'm trying to figure out which would result in the more efficient (gravity wise) mash/mash out/sparge...

Mash for 60 minutes @ 156*, then:

1. Lauter and completely drain first runs, add sparge water to grain bed to reach 168*, wait 20 minutes and lauter/mash out.

2. Add boiling water to raise temp to 168*, wait 20 minutes and lauter/mash out.

What, if any, are the pros/cons of each?

EDIT:

3. Perform step 2, then sparge at 168*.

 

[pvpeacock]

If I understand your question, Your first option is called a single batch sparge and your second is called no sparge. No sparge can also mean adding all your water at the beginning when you dough in and mash. The batch sparge should provide greater efficiency according to what I have read.

By the way, there is no need to wait 20 minutes using either method. Just add the extra water, stir the heck out of it and drain it (Volauf obviously). In addition, you don't need to hit a specific temperature when you sparge. I would just make sure you use water that is around 168-170.

 

[corypedia]

If I understand your question, Your first option is called a single batch sparge and your second is called no sparge. No sparge can also mean adding all your water at the beginning when you dough in and mash. The batch sparge should provide greater efficiency according to what I have read.

By the way, there is no need to wait 20 minutes using either method. Just add the extra water, stir the heck out of it and drain it (Volauf obviously). In addition, you don't need to hit a specific temperature when you sparge. I would just make sure you use water that is around 168-170.

Got it thanks for the info. What about option 3? Any more efficient than option 1? Ultimately I'm trying to figure out which profile to select in BS2 for my Igloo water cooler MLT...

 

[Yooper]

Got it thanks for the info. What about option 3? Any more efficient than option 1?

A sparge will tend to be more efficient than no sparge, but you can sparge in any of those options anyway, so it's really not any different.

 

[pvpeacock]

Check these out. They are very helpful:

http://brulosophy.com/how-i-brew/processes/batch-sparge/

http://brulosophy.com/how-i-brew/processes/no-sparge-method/

I typically do a double batch sparge myself. But have also done no-sparge as you described as option 2 with great success.

 

[doug293cz]

A mash out only increases efficiency if your starch to sugar conversion is incomplete at the end of the allowed mash time. If that is the case, the increased temperature speeds up the saccharification reactions. The speed up is for a short time however, as the high temp denatures the amylase in a few minutes. So the efficiency gain is simply due to more mash time (at a higher reaction rate.) If your conversion is not getting completed, the best way to remedy that is to mash for a longer time, and/or crush finer to get faster conversion.

A batch sparge increases your efficiency in the following way: If you don't sparge, the wort left in the grain due to absorption will be at the same SG as the wort collected in your BK. If your wort has an SG of 1.050, and the grain absorbs a gallon, then the sugar points due to grain absorption is 1 gal * 50 points/gal = 50 points. If you do a batch sparge, the grain absorption volume will be the same, but the retained sugar will be less. If your sparge run off had an SG of 1.020, then the sugar points lost to grain absorption would only be 20, so you picked up 30 points by sparging. (The preceding is a bit over simplified, but should give you the general idea about how sparging works.)

Brew on

 

[corypedia]

A batch sparge increases your efficiency in the following way: If you don't sparge, the wort left in the grain due to absorption will be at the same SG as the wort collected in your BK. If your wort has an SG of 1.050, and the grain absorbs a gallon, then the sugar points due to grain absorption is 1 gal * 50 points/gal = 50 points. If you do a batch sparge, the grain absorption volume will be the same, but the retained sugar will be less. If your sparge run off had an SG of 1.020, then the sugar points lost to grain absorption would only be 20, so you picked up 30 points by sparging. (The preceding is a bit over simplified, but should give you the general idea about how sparging works.)

Brew on

Thanks for the explanation. Helps to understand it. However, it seems like this would negatively impact the gravity of the first run and bring it's gravity down, due to the sparge not collecting as much sugar.

So I guess the question i still have would be, what would is the approximate difference in SG between draining 3 gallons on the first run and 3 gallons on the second run vs. draining 6 gallons with a mash out and no sparge?

is there any calculations that give a general percentage for these two options?

 

[doug293cz]

Thanks for the explanation. Helps to understand it. However, it seems like this would negatively impact the gravity of the first run and bring it's gravity down, due to the sparge not collecting as much sugar.

So I guess the question i still have would be, what would is the approximate difference in SG between draining 3 gallons on the first run and 3 gallons on the second run vs. draining 6 gallons with a mash out and no sparge?

is there any calculations that give a general percentage for these two options?

Now I gotta go do some real math. Yes, there are mathematical models for batch sparging. I'll try to do an example after dinner.

Brew on

 

[Singletrack]

Now I gotta go do some real math. Yes, there are mathematical models for batch sparging. I'll try to do an example after dinner.

Brew on

Dinner? We've no time for that. Math it up, dammit!

 

[Derek1985]

Dinner? We've no time for that. Math it up, dammit!

Equal runnings! From Denny's "Easy Batch Sparge":

Highest efficiency is achieved with a relative equilibrium between first and second runnings. You'd have to "topoff" your mash before you drain your first runnings. So:

You desire 7 gallons pre-boil volume. You have 10 lbs. of grain and desire 1.25 qts/lb water to grist. Thats 3.125 gal strike. In order to theoretically gain max efficiency you'd want a "topoff" value of:

3.5 gal - 3.125 gal = 0.375 gal

You then sparge with 3.5 gal. Denny comments that it is not necessary to be right on the money. Within 1 gal of each other supposedly does the trick.

EDIT: I did not fully read the post and believe this response to be erroneous!

 

[doug293cz]

Dinner? We've no time for that. Math it up, dammit!

I need nourishment before taking on the task of writing one of my epic posts. Who knew the masses had such a rampant hunger for math. I always say: "Be careful what you wish for, you might get it." So, here goes.

...

A couple hours later, I realize this is going to be much more difficult to explain correctly, and take longer to write than I expected. Hold your breath everyone, I will get to it.

Brew on

 

[corypedia]

Looking forward to it and waiting with abated breath

 

[doug293cz]

Ok, let's try an over simplified example that will be quicker to write and easier to follow than an analysis of a real mash. It will still illustrate the basic behavior of a batch sparge vs. no sparge process. We will ignore the grain, and just use sugar and water, and so that we don't have to switch back & forth between volume and weight, we'll just do everything in volume & volume %.

For the no sparge case, let's say we start with a mash that contains 9 gallons of water and 1 gallon of sugar. The solution is then 1/(1+9) = 10 vol% sugar. If we drain 8 gallons of the solution into the BK, then the BK contains 8 * 0.1 = 0.8 gal of sugar, and 0.2 gal of sugar remains in the MLT (as grain absorption or undrainable volume, makes no difference.) Our mash efficiency is then 0.8 gal / 1 gal = 80% (BK sugar / Total sugar.)

For the sparge case, let's say we have a mash that contains 5 gal of water and 1 gal of sugar. The solution is then 1/(1+5) = 16.67 vol% sugar. If we drain 4 gal of solution into the BK, then the BK contains 4 * 0.1667 = 0.6667 gal of sugar, and 0.3333 gal of sugar remains in the MLT, along with 1.6667 gal of water. Then we sparge by adding 4 gal of water to the 2 gal of solution in the MLT. The MTL now contains 6 gal of solution, 0.3333 gal of which is sugar. So, the sugar concentration in the MLT is 0.3333/6 = 5.556 vol% sugar. We then run off another 4 gal of wort into the BK. The sugar content of this wort is 4 * 0.05556 = 0.2222 gal. Thus the total sugar in the BK is 0.6667 gal (from first runnings) + 0.2222 gal (from sparge runnings) = 0.889 gal. Thus we recovered an extra 0.089 gal of sugar by batch sparging, and our mash efficiency went from 80% to 88.9%.

Yes, that really is the simplified version. I'll try to finish the "real" mash analysis write up in all its gory detail Thursday.

Brew on

 

[corypedia]

Ok, let's try an over simplified example that will be quicker to write and easier to follow than an analysis of a real mash. It will still illustrate the basic behavior of a batch sparge vs. no sparge process. We will ignore the grain, and just use sugar and water, and so that we don't have to switch back & forth between volume and weight, we'll just do everything in volume & volume %.

For the no sparge case, let's say we start with a mash that contains 9 gallons of water and 1 gallon of sugar. The solution is then 1/(1+9) = 10 vol% sugar. If we drain 8 gallons of the solution into the BK, then the BK contains 8 * 0.1 = 0.8 gal of sugar, and 0.2 gal of sugar remains in the MLT (as grain absorption or undrainable volume, makes no difference.) Our mash efficiency is then 0.8 gal / 1 gal = 80% (BK sugar / Total sugar.)

For the sparge case, let's say we have a mash that contains 5 gal of water and 1 gal of sugar. The solution is then 1/(1+5) = 16.67 vol% sugar. If we drain 4 gal of solution into the BK, then the BK contains 4 * 0.1667 = 0.6667 gal of sugar, and 0.3333 gal of sugar remains in the MLT, along with 1.6667 gal of water. Then we sparge by adding 4 gal of water to the 2 gal of solution in the MLT. The MTL now contains 6 gal of solution, 0.3333 gal of which is sugar. So, the sugar concentration in the MLT is 0.3333/6 = 5.556 vol% sugar. We then run off another 4 gal of wort into the BK. The sugar content of this wort is 4 * 0.05556 = 0.2222 gal. Thus the total sugar in the BK is 0.6667 gal (from first runnings) + 0.2222 gal (from sparge runnings) = 0.889 gal. Thus we recovered an extra 0.089 gal of sugar by batch sparging, and our mash efficiency went from 80% to 88.9%.

Yes, that really is the simplified version. I'll try to finish the "real" mash analysis write up in all its gory detail Thursday.

Brew on

Thanks for this. Makes sense.

 

[Magnus314]

0.2 gal of sugar remains in the MLT (as grain absorption or undrainable volume, makes no difference.)

You are my hero, and my faith in brewing science is restored

I recently experienced a decent bump in efficiency and couldn't figure out why... it's because I am now draining a tiny bit more wort before I sparge.

Small, but noticeable increase in efficiency.

 

[Singletrack]

Yes, that really is the simplified version. I'll try to finish the "real" mash analysis write up in all its gory detail Thursday.

Brew on

Very nice. Still looking forward to the partial differential equations. Go ahead and eat dinner first, as needed.

 

[doug293cz]

Very nice. Still looking forward to the partial differential equations. Go ahead and eat dinner first, as needed.

Apparently the appetizer isn't going to pass for the full meal. Back to the kitchen with me.

I don't think it will come to differential equations, or even calculus (unless you want to try to model fly sparging, and I'm not ready to go there.)

Brew on

 

[Singletrack]

Apparently the appetizer isn't going to pass for the full meal. Back to the kitchen with me.

I don't think it will come to differential equations, or even calculus (unless you want to try to model fly sparging, and I'm not ready to go there.)

Brew on

Don't do any extra work on my account... but I suspect this really isn't work for you. Thank you for putting some easy-to-understand numbers to batch sparging.