Loss Calculations

[Azurelimits]

So I just brewed a pumpkin spice beer last night and I had a couple questions about loss calculations. So my recipe called for steeping about 2# of grain and 6.6# of lme, 1 oz of gouldings at start and I added in pumpkin pie spice as well as yeast neutriant and irish moss at 15min. I steeped the grains for 30 min and let the excess drain out (I dont squeeze the bag).

So here is where my question comes from. How do I account for volume loss to grain, hops and additives? The valve in my keggle is a little high and I have a copper tube to help draw beer up from the bottom and I need to account for a little loss there. I started with about 7.5 gallons and ended up with just about 5.5 gallons in my primary. I guess 1 gal loss in boil off may be ok but 3/4 gal loss to grain, hops and additives seems a little high. I assume 1/4 gal loss to the bottom of the keggle.

Does this sound right to anyone else?

 

[halite]

You also need to account for the loss during cooling. The loss to grain is pretty standard at 0.15 - 0.2 Gallons per LB, while the loss to hops depends on the type of hops (pellet, whole leaf etc). I would suggest that the loss to hops and additives will be minimal and so I tend not to include these in my calculations. The key losses are:

Grain absorption
Mash Tun dead space (not relevant here)
Evaporation during the boil
Loss during cooling
Kettle Dead Space

It takes a few brews before you can accurately work out what each of these values are, as everybodies system is different. Make notes during each brew and before too long you will have a very accurate picture of the subtlties of your system

 

[dzlater]

You also need to account for the loss during cooling. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

How does one lose wort during cooling?

 

[halite]

How does one lose wort during cooling?

As far as I know you exprience some loss during cooling as the wort rapidly cools from boiling to pitching temp. You would expect to lose about 4% during cooling, this is down to the fact that the wort expands when hot and contracts when cooled. You won't lose a huge amount, but at 4% it is definitely noticeable.

 

[jcarson83]

I lose one gallon per hour of boil and usually figure on losing 1/2 to 3/4 with the hops and cold break. I don't worry about the grains because I measure the volume just before I start the boil to estimate if I need to add more or boil off longer.