Fly sparging question

[jlogue3454]

I've done several brews with fly sparging, but I'm getting around 67-70% efficiency. My question is, if you let all of the sparge water drain into the mash tun well before you're done sparging, does this hurt your efficiency?

 

[Ravenshead]

No, as long you go slow until you get a couple of inches of water above the grain bed you should be good. The idea is to keep the grain bed intact and use pressure from the clean water above it to drive the sugars out. As long as you don't cause channelization via disturbing the bed you're good. I suppose building up a foot or so of pressure head above the grain bed may also cause channeling but that's a pretty excessive case.

If you're getting consistent efficiency I wouldn't mess with any thing. Consistency is what you're looking for.

 

[jlogue3454]

thanks ravenhead, I'll have to do some more tweaking to figure out my efficiency issues.

 

[Smellyglove]

How do you drain?

 

[Jaybird]

No not really but its not the optimal thing to do. What's your Sparge water temp? I shoot for 175* leaving the HLT knowing its going to drop about 5 to 10 deg by the time it hits the grain bed. I keep about 2 inches of water on top of the grain bed..

Cheers
Jay

 

[jlogue3454]

How do you drain?

I start slow to set the grain bed, vorlauf, then I usually sparge for 45-60 min.

 

[jlogue3454]

No not really but its not the optimal thing to do. What's your Sparge water temp? I shoot for 175* leaving the HLT knowing its going to drop about 5 to 10 deg by the time it hits the grain bed. I keep about 2 inches of water on top of the grain bed..

Cheers
Jay

I usually make sure it's at 169 leaving thr HLT, I didnt think it would experience that much of a temp drop. You don't get extra tannins from sparging that hot?

 

[Yooper]

I usually make sure it's at 169 leaving thr HLT, I didnt think it would experience that much of a temp drop. You don't get extra tannins from sparging that hot?

Sparging with 175 degree water won't cause tannin extraction. First, the grainbed isn't going to get that warm (I lose about 4 degrees but others lose more or less in the water as it moves), and secondly tannin extraction is a function of pH. If the pH doesn't raise above about 6, then there would be no tannin extraction.

 

[Jaybird]

I usually make sure it's at 169 leaving thr HLT, I didnt think it would experience that much of a temp drop. You don't get extra tannins from sparging that hot?

Nope not at all. Tannins is a product mostly of PH not temp. Decoction anyone? But, I have about 6"-8" drop from my HLT to the top of a normal grain bed through my sparge ball. From the time it leaves the HLT to the top of the 2" cap I get about 5 deg drop. Then it has to sit there with all its other hot water buddies till it get its turn to play in the mash party....
Next time you brew take a good temp reading of the very top of the grain bed with your 169* water. You might be surprised to find out your only sparging with 163-164* water on the grain bed.

Cheers
Jay