Low Fly Sparge Temp and Efficiency

[AT-JeffT]

Hey Everyone,
I just picked up a cooler mash tun and turkey fryer.

Today I had a stuck sparge (poor manifold) and I ended up shoveling out the mash and replacing my manifold with a large nylon bag. The nylon bag worked really well, but when I got around to (fly) sparging my sparge water was 134F.

I had 67% Brewhouse efficiency overall. This should be better as I was getting slightly better when I was doing stovetop BIAB partial boils (3.5gal).

My question is did my 134F sparge temp drop my efficiency down the 10-15% I am looking for?

 

[AT-JeffT]

I also forgot to acidify my sparge water. It is my understanding sparge ph is only for tannin extraction not sugar exaction. Correct?

 

[tripplehazzard]

Did you use rice hulks? How much was the grain bill.did you fly sparge or just dump water on top? You probably had a low efficiency due to the temp of the water you sparged with. I think we sparge around 160 to stop the sugar conversion.

 

[tripplehazzard]

Did the mash tun stay at a steady temp while you where mashing? Sorry so many questions. I just want to help you where I can. You know a pretty normal efficiency is around 70-75. So you really weren't too far off man especially for your first AG brew

 

[AT-JeffT]

14lbs no rice; I had absolutely no issues once I used the nylon bag. The recipe was to be an RIS now probably a American Stout. Mash temp stayed steady.

I fly sparged. Kept the water 1" above the grain bed, it dipped below a few times. Ran about .5qt a min(slow for big beer).

I was doing a traditional 1.25qt/lb mash stovetop and a single 1.25gal batch sparging for a 3.5gal boil and getting 69-71% efficiency. I really should be getting much better efficiency now that I can sparge with 3 more gallons.

 

[Denny]

My question is did my 134F sparge temp drop my efficiency down the 10-15% I am looking for?

No. It was either the crush or your procedure...maybe both.

 

[Denny]

I also forgot to acidify my sparge water. It is my understanding sparge ph is only for tannin extraction not sugar exaction. Correct?

Pretty much correct. The way you set things up using a bag is not optimal for fly sparging. My guess is that's where you lost your efficiency.

 

[AT-JeffT]

No. It was either the crush or your procedure...maybe both.

Could you explain a bit further? My crush was finer than when I was doing stovetop BIAB.

 

[Denny]

Could you explain a bit further? My crush was finer than when I was doing stovetop BIAB.

But it's possible that it still wasn't fine enough. Dunno, just a WAG since I didn't see it. But if you think it was fine, then it's probably your sparge procedure. Did you happen to test your conversion efficiency?

 

[AT-JeffT]

But it's possible that it still wasn't fine enough. Dunno, just a WAG since I didn't see it. But if you think it was fine, then it's probably your sparge procedure. Did you happen to test your conversion efficiency?

The first runnings were 20.8 Brix or 1.087. I couldn't find a formula for conversion efficiency. Any help would be appreciated.

 

[karzak]

How was your mash pH? Givin that you acidified the water, and the RIS recipe presumably had a decent % of dark specialty grains, you might have ended up a bit too acidic and not gotten great mash effeciency.

Also, 67% isn't really that low. It's hard to know what causes the difference between 75-80% and 65-70% without being very knowledgeable of your setup and taking good data on brew day.

Just my .02

 

[AT-JeffT]

How was your mash pH? Givin that you acidified the water, and the RIS recipe presumably had a decent % of dark specialty grains, you might have ended up a bit too acidic and not gotten great mash effeciency.

Also, 67% isn't really that low. It's hard to know what causes the difference between 75-80% and 65-70% without being very knowledgeable of your setup and taking good data on brew day.

Just my .02

Mash ph was good around 5.5 (tested with strips)

 

[Denny]

The first runnings were 20.8 Brix or 1.087. I couldn't find a formula for conversion efficiency. Any help would be appreciated.

http://braukaiser.com/wiki/index.php?title=Understanding_Efficiency#Conversion_efficiency

 

[AT-JeffT]

I made a (2.5gal) batch of wort for starters today.

I noticed a 10F drop when transfering the sparge water from the kettle to the HLT.

I added taking grain bed temps to my sparge process. I saw temps of mid 140's with 170F sparge water. Next full brew I will be upping my sparge water temps in order to raise the grain bed temperatures. I am also considering heating the sparge water in two batches as my HLT is uninsulated and loosed heat badly.