Different kind of efficiency problem. Help please!

So I upgraded my mash tun recently to a bigger cooler and a stainless braid/ball valve contraption. I have since made 4 batches, and I have gotten very high efficiency numbers for them:

1. 16.75 lbs of grain, preboil gravity = 1.043 in 13.75 gallons, ~95% efficiency.
2. 10.5 lbs grain, PBOG = 1.044 in 7.5 gal, ~87%
3. 10.25 lbs grain, PBOG = 1.040 in 8.5 gal, ~90%
4. 16.5 lbs grain, PBOG = 1.044 in 13.75 gal, ~95%

(I used this calculator to get the numbers: Brewhouse Efficiency Calculator | Brewer's Friend)

*I am 100% sure of the volumes, and the gravity readings were taken at 60*F.

At first, I was like "Sweet! This new cooler works great!" Then I read a thread a few days ago about high efficiencies and now I'm like "OH NO TANNINS!!"

I should also mention that I fly sparge. Also, batches 1 and 4 above were the same recipes (Centennial Blonde FTW!). None of these beers came out poorly - in fact, the first three taste great, and the 4th was fine at bottling.

So I guess my questions are:

1. Is it bad that I'm getting gravities like these?
2. How much should I worry about tannins?
3. If I run the wort out of the tun faster, I will reduce my efficiency, right? Should I do this?
4. If my late runnings are below 1.010 and I don't have my desired volume yet (or if the gravity is too high), would it be better to top off with straight water?

Mind you, I'm not going out of my way to get high extraction rates, it's kindof just happening.

Thanks in advance, guys!

-Drew

Every system has it's limits. One system may be able to get 95% efficiency without decreased wort quality while another might not. If your beer tastes great then it looks like you're fine. If you can't taste tannins then I wouldn't worry about it. It's not that high efficiency is bad, it just increases the chance of extracting poor quality wort.

IMO, don't run it faster. It would lower your efficiency but I don't think it would really help anything...you'd just lose efficiency.

I think it would be worthwhile to measure the gravity of the last runnings using your new system and process just to see what you get. If the gravity of your last runnings are getting low, like 1.010, then stop. Yes you prob would be better to top off with water in that case.

What I do is to just not put the last 2 qt. or so of runnings in the kettle even though they are still running above 1.010. I account for the water volume and efficiency hit when devising the recipe. Often I freeze and later use this low-gravity reserved wort for yeast starters.

I disagree about not running faster. Why wouldn't you? Just try it and see what kind of numbers you get for your system.
Once I establish my grain bed, I fully open up the valve (connected to a 5/16" ID hose) and use the "hybrid" sparge technique in the sticky and get 80% efficiency. I'm very happy with this number and my sparge time is about 15-20mins to get about 6.6 gallons for the boil.

You are fly sparging with a braid and still getting those efficiencies?

double_e5 said:

You are fly sparging with a braid and still getting those efficiencies?

Click to expand...

Is this true. I'm puzzled as well and I don't even fly sparge.

double_e5 said:

You are fly sparging with a braid and still getting those efficiencies?

Click to expand...

Yes. Actually, I do that 'hybrid' fly sparge thing...

I just checked that sticky again (I had forgotten about it) and that's pretty much how I sparge but I've always just called it fly sparging (saucepot and all)...I don't see anything 'hybrid' about it but whatever.

I disagree about not running faster. Why wouldn't you? Just try it and see what kind of numbers you get for your system.
Once I establish my grain bed, I fully open up the valve (connected to a 5/16" ID hose) and use the "hybrid" sparge technique in the sticky and get 80% efficiency. I'm very happy with this number and my sparge time is about 15-20mins to get about 6.6 gallons for the boil.

Click to expand...

Even in that sticky it says that draining faster will hurt efficiency...but you're right that it's only 'to a point'. As I said in my first post, every system has it's limits. If one system has a grain bed that's twice as wide as it is tall vs. another grain bed that's twice as tall as it is wide...they would perform differently regarding drain rate. But frogfree is right that you should experiment with the drain rate...no sense draining slower than you need to.

Thanks for all the replies.

I think I'm definitely going to run the wort out faster and see what happens... It feels like it takes forever to collect enough. Besides, I don't care about 70 or 80-something % extraction as long as it's consistent. And if the wort is better off, all the better.

I'm still wondering what the consensus is about topping off with straight water if your late runnings are too thin, though...

Topping off would be fine. All you are doing is adding water to get to your boil volume.