Monday, October 13, 2008

Brew 9:Winter Warmer with Notes on Batch Sparging

Brad and I went in on our equipment for the first few brews, to reduce our exposure in case we didn't want to continue, and to help us get started faster. I bought the burner and pot for our first extract, he bought the Carboy and the rest of the equipment.

As we continued to brew, I slowly added to my equipment list until I had everything to brew all-grain, and now he is doing the same. Two weeks ago Brad and I brewed a Winter Warmer at his house, using his equipment with the exception of my Mash/Lauter Tun as he is still building his (more on that once it is done). We only had two vessels so I assumed that we could batch sparge, but the results were terrible efficiency.

After re-checking the procedure, I now realize that batch sparging still requires 3 vessels:
  1. A mash/lauter tun (holds the grain over a false bottom)
  2. A Hot liquor tank (maintains clear water at 170 degreees)
  3. A boil kettle, or a runoff vessel capable of holding the total volume of Wort.
The reason you can't do it with two vessels is because you actually have to sparge 3 times to get decent efficiency:
  1. After the mash is complete, add enough water to increase temp to 160, then recycle until clear, then sparge until the runoff slows.
  2. Add half the remaining sparge water (heated to 170), recycle until clear, then sparge until the runoff slows.
  3. Add the remaining sparge water (heated to 170), recycle until clear, then sparge until the runoff slows.
On low gravity batches, if you are willing to accept very low efficiencies, you can reduce the number of steps. Since we only had 2 vessels we added all our sparge water to the mash and drew the wort of in one large batch sparge. While our target gravity was 1.088, we only achieved an original gravity of 1.070, a huge difference! There was no way we could have achieved 1.088 with that equipment unless we lowered our yield to 4 gallons, and boiled off an additional gallon to thicken the wort.

What we did instead, once we realized our beer would have too much bitterness for the gravity we achieved, was boil 2 lbs of Dry Malt Extract (DME) into 2 quarts of wort and add it to the primary to boost the gravity to somewhere near our target and hope for the best.

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