Batch Sparge Question

I just formulated my recipe (American Wheat) in Beersmith and my Single Infusion Batch sparge is calling for:

Round 1 Sparge of 1.22 Gallons and

Round 2 Sparge of 3.63 gallons

Why does it divide the two amounts so differently??? 1.22 gallons just seems like a small first sparge. I was tempted to just add the two together and divide by two.

There is obvioulsy a logical reason beersmith is recommending this, what is it?

mangine77 said:

I just formulated my recipe (American Wheat) in Beersmith and my Single Infusion Batch sparge is calling for:

Round 1 Sparge of 1.22 Gallons and

Round 2 Sparge of 3.63 gallons

Why does it divide the two amounts so differently??? 1.22 gallons just seems like a small first sparge. I was tempted to just add the two together and divide by two.

There is obvioulsy a logical reason beersmith is recommending this, what is it?

Click to expand...

It must be the settings in your Beersmith set up. When you click on the edit for this mash profile, it'll give you a check box to check to split it evenly.

YooperBrew said:

It must be the settings in your Beersmith set up. When you click on the edit for this mash profile, it'll give you a check box to check to split it evenly.

Click to expand...

So when I clicked that button it changed it to one 4.86 gallon sparge? I thought you wanted to do at least a 2 round sparge for efficiency?

This thread prompted me to do something I've been planning on doing for a bit. Comparing some different sparge methods so I made up a quick excel sheet to do some testing. This sheet was just to show concentration reductions of different batch sparge methods.

I had to make some assumptions though. First is the volume of remaining liquid in the MLT stays constant, which is not a bad assumption. I used 2.5 gallons of wort that remains in the MLT. This is to account for dead space under the false bottom, grain absorption, and water the just doesn't drain out. This is the unrecoverable wort from the MLT that you leave in there every time. In theory this could reduce over time but I don't know how much and I doubt it would be enough to make a huge difference.

Next I had to assume when you put the new batch sparge in there you had perfect equalization of the remaining wort with the sparge water. This will not account for time it takes to transfer sweet wort out of grains, etc. This assumption isn't correct, but how far off I cannot tell. Would depend on a lot of factors too. But, then again, this isn't a bad assumption to make for this review and won't change the results as I cannot see it changing the order of any methods.

I used a starting concentration of 454 grams per gallons. This number really doesn't change anything though except concentration I'm working with, let assume it's sugar, but it's really everything in the wort. Changing this number will not change the order of the methods, only the amount of sugar left behind by each method.

I did four tests. A one step batch sparge with all the sparge water, a two step batch sparge with 50/50 split of sparge, two step with 25/75 split of sparge like first post, and three step batch with even split.

I used a sparge volume of 4.5 gallons. This will not change how the different methods rank either. Here are the results, number to the right is amount of the 454 g/gallon of sugar left behind in the MLT, i.e. total weight of sugar left in MLT.

One Step Sparge - 405 grams
Two Step Sparge, 50/50 - 314 grams
Two Step Sparge 25/75 - 333 grams
Three Step Sparge, 33/33/33 - 277 grams

Now, Percent of original Sugar Removed

One Step Sparge - 64%
Two Step Sparge, 50/50 - 72%
Two Step Sparge 25/75 - 70%
Three Step Sparge, 33/33/33 - 75%

I did verify that changing the total Sparge volume does not change order of methods and changing the starting sugar concentration does not change the percent of original sugar removed.

So, what will raise the efficiency higher? That's right, remaining volume in the MLT!

I lowered it from 2.5 gallons to 2 gallons.

One Step Sparge - 69%
Two Step Sparge, 50/50 - 77%
Two Step Sparge 25/75 - 76%
Three Step Sparge, 33/33/33 - 83%

That's an average increase of 5.44 percent!!

Now, I don't have a print screen button on this apple keyboard and it's the first time I've actually needed it in awhile so no screenshot of the Excel sheet. These are the results I kind of expected though. I did the One Step Sparge by hand to check my excel sheet. If anyone wants to check my work for me, then here are a few pics of it. I treated it as a basic leaching/extraction process.
http://i15.photobucket.com/albums/a365/Intel486/food/Beer/batchmath.jpg
http://i15.photobucket.com/albums/a365/Intel486/food/Beer/batchmath2.jpg
http://i15.photobucket.com/albums/a365/Intel486/food/Beer/batchmath3.jpg

If I understand your point from this experiment, more rounds of batch sparging and the most efficent manifold is one answer to better efficency. I just moved to a copper manifold in hopes of keeping it on the bottom of the cooler. I kept hitting my braid with my mash paddle and working it up causing a poor incomplete drain. We'll see.

mangine77 said:

I just formulated my recipe (American Wheat) in Beersmith and my Single Infusion Batch sparge is calling for:

Round 1 Sparge of 1.22 Gallons and

Round 2 Sparge of 3.63 gallons

Why does it divide the two amounts so differently??? 1.22 gallons just seems like a small first sparge. I was tempted to just add the two together and divide by two.

There is obvioulsy a logical reason beersmith is recommending this, what is it?

Click to expand...

I had the same issue at first. Go into Mash Profile details and make sure you check off 'Sparge using equal size batches' and "Drain mash tun before starting batch sparge'. Then you have to change the percentage of mash tun volume. I have a 10 gallon cooler and using 70% will give me equal batch sparge amounts. If it doesn't work with that number, just mess with the percentage until it gives equal amounts.

thebull said:

If I understand your point from this experiment, more rounds of batch sparging and the most efficent manifold is one answer to better efficency. I just moved to a copper manifold in hopes of keeping it on the bottom of the cooler. I kept hitting my braid with my mash paddle and working it up causing a poor incomplete drain. We'll see.

Click to expand...

There are various things this shows to improve efficiency. Across all methods, increasing total sparge volume and reducing water left in the MLT will increase efficiency. Water being left in the MLT is hard to change since you're not going to get around grain absorption so the only thing you can do is reduce dead space in the MLT as much as possible, such as under your false bottom and water that just won't physically drain out due to MLT design (space below valve).

Now, with a leaching/extraction process like we're performing, splitting up the same volume of wash water into smaller amounts will always increase efficiency. Think of it like this, when you're pulling your sweet wort out of the MLT between each batch sparge, the liquid you're leaving behind cannot be any sweeter than what you've always drained out. So, you drain out wort of 1.040, then all the remaining liquid in the MLT is also going to be 1.040. Then you add some sparge water and dilute the 1.040 wort down to say, 1.020. You drain that out and all the wort left in the MLT will be 1.020 now. So, basically you're trying to find a way to get the gravity down as low as you can without oversparging.

So, here's what I've done.
We're going to sparge with 4 gallons of water, 2.5 gallons remain in the MLT, and the starting concentration is 454 grams /gallon.

1 Step Batch Sparge of 4 gallons
Final Concentration will be 174.61 grams / gallon

2 Step Batch Sparge of 2 gallons each
First Sparge, concentration of 252.2 grams / gallon
Second Sparge, concentration of 140 grams / gallon <--- Lower than 1 step

3 Step Batch Sparge of 1.33 gallons each time
First Sparge, concentration of 296.08 grams / gallon
Second Sparge, concentration of 193.1 grams / gallon
Third Sparge, concentration of 125.92 grams / gallon < --- Lower than 2 step

So, the more times we wash, the lower we can get the final concentration.

There is a demonstration you can do at home to show this nicely. If you're interested I can tell you but you'll need a large empty bottle (like a 2 L bottle or a large gatorade bottle, food coloring, some empty glasses (4 should do) and a measuring cup.

For these to actually work I also have to make an assumption that when you do add your batch sparge water that all the remaining liquid in the MLT will equalize and mix evenly with the water. Also, lower concentration wort will cause a bigger difference between anything remaining in the grains and hopefully help you leech out some more sugar. Now, how much that actually helps I don't know off hand.