Batch Sparge: Rest or No Rest?

For my first AG batches, I had a couple of efficiency struggles. Every time I brew beer, I try to make changes to my system and methods until I find the one that pleases me the most.

This time around, I bought a barley crusher grain mill, and hope that will resolve the majority of my issues. However, I also think the way I batch sparged may have impacted poor efficiency.

The first time around I tried using a "hybrid" approach where I batch sparged half the amount, and then fly sparged the second half with a bucket with holes. I think I messed that up by draining much faster than sparging.

The next time around I switched to double batch sparging. After mashing and draining, I heated my sparge water to 185~ and mixed it with the grain for about 5 minutes, vorlaufed, and repeated twice. Note, it was a cold day, so during the 5 minutes of mixing I did lose quite a bit of temperature in the grain bed.

So when batch sparging, what is the important factor? Maintaining the temperature as close to 170 as possible while mixing the grain; or simply mixing the grain well?

Sugar is more soluble at higher temps, so does that mean I should just mix really really well for about 1-2 minutes (rather than mix and rest 5-10 min) then begin vorlauf and drain?

Edit: Not trying to start a debate of any kind, simply improve my process through more experienced member's experiences.

Temperature during sparge shouldn't matter much. Your sugars have already dissolved, and in any case solubility is plenty good at even room temperature.

Batch sparging is pretty fool proof so long as you mix thoroughly. Have you tried using Kaiser's diagnostic tools? http://braukaiser.com/wiki/index.php?title=Troubleshooting_Brewhouse_Efficiency

Thanks for the reply! I've browsed through it, but I'll go ahead and thoroughly read the whole thing now that I have time.

On a side note, you think it would be more effective to mix well for about 10 minutes than mixing well for say 3 minutes and draining?

I've had good luck with just a minute or two of good mixing. I definitely let it settle for 5-10 minutes, though, to let everything work its way out. Do that twice, and I've been overshooting my efficiency numbers, even. If you can get the sparge water in contact with all the sugars, especially with two rinses I think you'll be well off. As MalFret said, the temperature shouldn't be an issue, just the exposure and removal.

I don't know that 10 minutes as opposed to 3 minutes would really make a difference, but might as well try every tool in the shed.

Along the lines of what MalFet said, from what I understand the temperature is not very important as the sparge is simply rinsing away sugars from the grain. Some research that John Palmer talked about once upon a time also showed that tunnels, or easiest paths form in your grain bed, and fly sparging sometime isn't very efficient as all the sugar is removed from these channels that the water flows through but not from the rest of the grain bed. So, in that case, batch sparging is better as it tends to soak up the sugars from the entire grain bed. This is especially true if you only have a small output for your wort.

I think the most important thing is that your grain mill, giving a consistent crush, will help with the consistency of your efficiency. I batch sparge and my efficiency is only in the high 60s but I get about the same efficiency every time, so I'm happy to spend a couple extra dollars per batch to know what to expect.

Right. Good input. I like how MalFet says its pretty much "fool proof". I was a little concerned because I was even considering doing a single batch sparge, but if I mix for about 3-4 minutes, and then vorlauf and drain, I'm looking at a 5-6 minute batch sparge process. That sounds like I'm missing something.

Sounds like you are changing things up too much and should consider sticking to one method for multiple batches. Just try to dial in one method and make it consistent so you can hit your numbers.

spenghali said:

Sounds like you are changing things up too much and should consider sticking to one method for multiple batches. Just try to dial in one method and make it consistent so you can hit your numbers.

Click to expand...

I would agree with this, adding that once you feel you've dialed one method , then move on to another if you need to.

Others may disagree, but I'd be cautious with the double batch sparge. The pH of your mash drops each time you sparge and if it drops too low you can extract tannins from the husks. I ended up with a pretty astringent pale ale due to (what I believe was) over sparging.

That said, if your beers are turning out fine, ignore the above. I also wouldn't stress about efficiency unless your numbers are really bad. If you have a process that produces good beer, go with it.

I would agree with watching pH problems with too much sparging. The pH actually drops less to release tannins though. With the water starting at around 7.5 it needs to drop down near 5 and does so with the grain to water ratio. I believe that introducing more water sparging can lead to the pH to climb back up above 6 where tannins can be an issue.

I used to double batch sparge, but have come to the conclusion that it's a waste of time. Now I just heat up all my sparge water until it reaches boiling and add enough to bring my mash up to mash out temps (168). I stir and let it sit for 10 mins. Then I collect my first runnings after vourlauf. Add the rest of my sparge water, stir well and let sit for 10 mins. Simple and effective

Thanks guys, I hadn't considered over-sparging and releasing tannins. I got two batches this weekend, and I'll go ahead and try a single batch sparge. I was trying to stay away from mashing out, because I read on Kaiser's wiki that although it can result in slightly higher efficiency, it can also lead to less fermentables and ultimately less attenuation.

That said, if milling my grain and single sparging doesn't work, I'll try mashout as flabyboy described.

As mentioned before, I'm trying to change 1-2 things at most per batch until I feel satisfied with the method. From there on, I'll just fine tune that method.

Thanks all so far.

flabyboy said:

I used to double batch sparge, but have come to the conclusion that it's a waste of time. Now I just heat up all my sparge water until it reaches boiling and add enough to bring my mash up to mash out temps (168). I stir and let it sit for 10 mins. Then I collect my first runnings after vourlauf. Add the rest of my sparge water, stir well and let sit for 10 mins. Simple and effective

Click to expand...

and no issues with any off-flavors adding boiling water to the grain bed? Curious because I'd prefer this method.

There was a big thread on batch sparging last week so you can search that. One of the guys on that thread is Denny Conn. He has a little experience under his belt. I used his method of batch sparging this week and my efficiency went from 68 to 78%. Here is the link to his website. http://hbd.org/cascade/dennybrew/

Now that I have finally retired my Bag; I use Denny's process too. Just as easy as BIAB.

Actually, I got most my ideas from Denny and reading last weeks thread. The few things I didn't get from that thread I asked here.

It was funny how that one guy kept being skeptical about Denny and his methods.

Yes that was a little strange. If there is one thing I have learned on this forum is there are alot of different ways to do things. I have only done two partial mashes and I pretty much followed Denny's process the second time with great results so I believe in that process. Good luck!

tre9er said:

and no issues with any off-flavors adding boiling water to the grain bed? Curious because I'd prefer this method.

Click to expand...

No. The grain bed is being stirred as I add. Never gets over 168. pH is more important than temp anyway. Add a little phosphoric or lactic acid to your sparge water to get it around 5.5 and you have no worries

Cacaman said:

Thanks guys, I hadn't considered over-sparging and releasing tannins. I got two batches this weekend, and I'll go ahead and try a single batch sparge. I was trying to stay away from mashing out, because I read on Kaiser's wiki that although it can result in slightly higher efficiency, it can also lead to less fermentables and ultimately less attenuation.

That said, if milling my grain and single sparging doesn't work, I'll try mashout as flabyboy described.

As mentioned before, I'm trying to change 1-2 things at most per batch until I feel satisfied with the method. From there on, I'll just fine tune that method.

Thanks all so far.

Click to expand...

By the time your mash has completed all your starches should be converted to sugar. Not sure how a mash out could reverse what just happened over an hour mash. The mash out is just supposed to stop the enzymes from converting any further before the boil. Not a necessary step, but it works well with my setup

The only thing I would add to his steps are to add hot water to the cooler. This heats up the insulation and allows for very little temp loss during mashing. And the other would be to double check your valves are closed on your mash laughter tun before adding strike water. ( ask me how I know)

Also I picked up the tip of putting tin foil with holes on top of my grain bed so when I recirculate the first runnings my grain bed is intact.

tagz said:

Others may disagree, but I'd be cautious with the double batch sparge. The pH of your mash drops each time you sparge and if it drops too low you can extract tannins from the husks. I ended up with a pretty astringent pale ale due to (what I believe was) over sparging.

That said, if your beers are turning out fine, ignore the above. I also wouldn't stress about efficiency unless your numbers are really bad. If you have a process that produces good beer, go with it.

Click to expand...

Carefull there - the pH of the mash rises with each sparge as the buffering capability of the grains is reduced. For that reason some of us acidify our sparge water to keep the pH under 6.0 and avoid tannin extraction.