Registered: 1157343156 Posts: 16
Reply with quote #1
I normally brew 12 gallon batches and I have a problem. I don't have enough room in the mash tun (converted keg) for all the grain needed for this Imperial Stout so I am thinking of splitting the mash in half and mashing in two converted kegs. The thing that I don't understand is the water needed for a 6 gallon batch is more than half as to doing a 12 gallon batch. If I load the 12 gallon recipe in promash it is telling me that there is "14.32 into kettle and "12.07 after boil" I can fit 14.32 in to my converted keg sounds good but I can't fit all the grain in the MLT. If I cut the mash in half and I do a 6 gallon batch, promash is saying "8.41 into kettle" and "6.16 after boil" then I won't be able to fit all the wort in to my boil kettle (8.41 x 2 = 16.82). The pre-boil gravities are also different cutting the batch size in half. What do I do? I am confused
Registered: 1084240186 Posts: 23
Reply with quote #2
I'm just guessing here, but in both instances you're losing 2.25 gallons to evaporation during the boil (14.32-12.07=2.25 and 8.41-6.16=2.25). But, you're losing 2.25 gallons once for the 12 gallon boil and twice for the 6 gallon boils. That's why you have to start out with more wort, and why the gravity is lower. Plus, you end up with marginally more wort with the two 6 gallon boils (12.32 gallons versus 12.07 gallons).
So, what you really have is 16.82 - 4.5 = 12.32 as compared to 14.32 - 2.25 = 12.07. Make sense?