Missing OG to the high side

[ChefDougAU]

I brewed my first large batch (11 gallons) today... all-grain Bavarian Hefe using EdWort's recipe. Per the recipe, my OG should be 1.052... mine was 1.062. Preboil and postboil volumes were right... I followed the recipe exactly... temps were good. What happened?

 

[ruger988]

Better efficiency than you expected? Have you brewed this before on a smaller scale? Just top it off with spring/distilled water until you hit the correct OG... more beer

 

[Qhrumphf]

Looks like if I used his recipe I'd end up about the same place that you would. Gravity errors with all-grain brewing are largely system based. Your system is more efficient pulling sugars out of the grains than the recipe accounted for. Most recipes seem to be in the 70-75% range (this one about 70%), and you're just over 80% efficiency, assuming that your postboil volume is 5.5 gallons. Lots of things that can cause this. The way you crush your grains, the way you lauter/sparge, whether or not you do a mashout, the temp of the sparge water, how far you sparge, etc.

Outside of a change based on gravity (higher efficiency for lower gravity, lower efficiency for higher gravity), if you find your efficiency is all over the place there's probably something inconsistent in your practice. But if your efficiency is consistent (at least at a given gravity range), then you just need to assume that for any all grain recipe you brew, and adjust the recipe accordingly. In this case, assume 82% efficiency and adjust grain bills accordingly (you'll typically need a little less grain than most recipes will list)

 

[ChefDougAU]

I have consistently either hit projected numbers or been slightly high... I have a simple gravity driven system... a 10 gallon Igloo with homemade bazooka tube... most times, I batch sparge in two batches allowing about 8-10 minutes per batch... on the second batch, I refire the water to exact temp as the first batch. I have only been brewing for about 10 months... I have not yet bought a mill, so I buy my grains already crushed.

 

[ChefDougAU]

Better efficiency than you expected? Have you brewed this before on a smaller scale? Just top it off with spring/distilled water until you hit the correct OG... more beer

I don't have room in the fermenters... these batches are 5.5 gallons each as it is... I'm going to have STRONGER beer...:rockin:

 

[Qhrumphf]

The problem with all-grain recipes is that results are based off of the system that they're brewed on. And different recipes are written with different efficiencies to hit the projected OG. When I write recipes they're based on my system and I'll default to 80% since that's where I end up with for most mid-range gravities, and then I'll adjust the expected efficiency for high or low gravity beers. Most recipes written by others seem to default to 75% in most cases, although some may be lower, some higher, and sometimes they don't say. If you're getting 80-85% you're going to be a little closer in most recipes than one based off of 70% or so like this is. You might want to use brewing software and punch recipes in there before you brew them to help dial it in. That'll help you figure out what efficiency a recipe is based on if it doesn't say, and then it'll help you alter recipes to fit your system.