[SiameseMoose]

Beat that!

OK, it means I almost certainly made an error in weighing out my grain. I just hope the error was in the base Pils malt, and not some astronomical error in the specialty malts. The beer is a Dubbel, and I knew before the boil that I was way over target gravity. I ended up diluting with an extra gallon pre-boil, and increasing my hops accordingly. Still, my target was 5 gallons at 1.069, and now I have 6 gallons at 1.073. I generally get pretty high efficiency, 85% or higher, but every now and again I get a batch near 100%, but never this high before. I just wish there were a way I could recheck my grain amounts. But I'm not complaining about extra beer!

(And just for the record, I am aware that it is possible to legitimately get greater than 100% efficiency. The highest I've ever heard of was the near 130% claim by DeKonick, in Antwerp. They grind their grain to powder, and use a high pressure filter to lauter. That's also why they have to filter the beer so much before it goes out the door.)

[tubercle]

Tubercle gets 109% on a regular basis but his was only after the blue stripes were added to the red cooler/mash tun.

[MDixon]

I once couldn't figure out why my runoff gravity was so high and later found out I had put in 4lb too much malt... 

[thatguy314]

Are you reading your malt spec sheets, or are you just using homebrewing software.  Homebrewing software has a good average number, but you could have an especially rich batch of malt on your hands as well.  The only true way to determine efficiency is to get the malt spec sheets.  For most homebrewing purposes this doesn't always make that big a difference, but I hear on the pro level it makes a tremendous difference.

That said, it seems like you figured out the cause of your problem.

[Podo]

Not to change the subject, but the title of this post reminds me of one of the early Simpsons episodes where Homer is in a tank of water and the doctor says "this isn't right, this man is 104% body fat" because Homer is eating a turkey leg.  "Hey, no eating in the tank."  Sorry, nothing more of value to add!

[Malticulous]

I tend to get much better extract from pills malts, over 83%. The 90 minute boil also helps with efficiency.

[MDixon]

Boiling doesn't change efficiency, because sugars are conserved...

[bonjour]

Boiling doesn't change efficiency, because sugars are conserved...

But boiling more wort because you are boiling longer to cover evaporation does increase efficiency.

[Mikey]

Boiling doesn't change efficiency, because sugars are conserved...

But boiling more wort because you are boiling longer to cover evaporation does increase efficiency.

It doesn't matter what your volume of wort is when you start the boil, your "efficiency" is still the same, even if you boil it down to a syrup. Now if you're saying that you sparge more to collect more sugar and then boil that down, then yes, your efficiency will increase a little.

[bonjour]

From the same malt bill

collecting wort for a 60 minute boil to have 5 gallons at completion
or
collecting wort for a 120 minute boil to have 5 gallons at completion

The 120 minute boil will have a greater efficiency
Both will make beer

[Hokerer]

From the same malt bill

collecting wort for a 60 minute boil to have 5 gallons at completion
or
collecting wort for a 120 minute boil to have 5 gallons at completion

The 120 minute boil will have a greater efficiency
Both will make beer

But the fact that you're boiling for 120 minutes has nothing to do with the efficiency.  The greater efficiency comes from the fact that you have to sparge more in order to get enough pre-boil volume to still end up with 5 gallons post-boil.

[bonjour]

OK,
But I wouldn't have to do that if I didn't boil for 120 minutes,  therefore the long boil is the cause of the increased efficiency.

Do you need the chicken to lay the egg, or do you need the egg to hatch the chicken,  That's not clear to me either.

Talking about chickens and eggs on a beer board,  I need to get a life

[tubercle]

Tubercle always thought efficiency was the ratio between the total available sugar in the malt vs. the amount actually extracted and had nothing to do with what gravity the wert ends up being.


 The post boil gravity takes into consideration Pre-boil gravity, evaporation, etc and that is where the grain bill is configured at a predicted efficency of extraction.

 Something like that....
 

[MDixon]

Maybe I should repeat myself??? Boiling doesn't change efficiency, because sugars are conserved...

The extracted amount of sugar does not change. Now if one COLLECTS more volume then they can potentially extract more sugars, but it has NOTHING to do with the boil.

[tubercle]

Maybe I should repeat myself??? Boiling doesn't change efficiency, because sugars are conserved...

The extracted amount of sugar does not change. Now if one COLLECTS more volume then they can potentially extract more sugars, but it has NOTHING to do with the boil.

  That was what Tubercle was trying to say. You said it shorter