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Old 10-16-2008, 03:55 PM   #1
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Default Technique for determining pre boil gravity with a split boil...?

I am boiling on a stove top so I have been splitting my wort into two 5 gallon kettles. As I am collecting my wort I drain into a measuring cup then dump into boil kettles.

So usually one kettle has all the mash water and part of the first sparge then the second has the remaining sprage water...

I wonder if I simply alternate which pot i dump the wort into I can get an fairly accurate pre boil gravity reading? What do other people do?

Also since I am splashing a bit dumping the wort into the kettles should I be worried about hot side aeration? Most of the time I try to pour down the side of the kettle to reduce as much splashing as possible...

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Old 10-16-2008, 04:45 PM   #2
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I would collect it in a larger container, take my preboil reading, and then split it up.

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Old 10-16-2008, 04:59 PM   #3
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I used to boil in two pots, and I did a "half and half" approach- put half of each runnings in each pot. Not really scientific, but my thought was that I wanted the SG approximately equal for the hops utilization.
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Old 10-17-2008, 04:31 AM   #4
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Collecting it all in a larger container and measuring the SG before splitting it into two boil kettles would work, but you could figure it out using "points" if you didn't have or want to use another container. If after sparging and before the boil you find that you have one kettle with 3 gallons of wort @ 1.063 and the other kettle has 3 1/2 gallons @ 1.038, the first kettle has 3 X 63 = 189 points. The second kettle has 3.5 X 38 = 133 points. Combined, you have 322 points and 6.5 gallons, or 322 / 6.5 = 49.5, or a SG of just under 1.050 for the pre-boil gravity. Boiled down to 5 gallons, the SG should be about 1.064.
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