So the general rule of thumb is 60 minutes per pound at 275 in the oven.
The thing is, I have two four pound briskets. Does the math still work out the same? Or should I calculate for four pounds?
A little more detail please. Are they in the same container or one on top of the other or something?
Side by side in the oven it with some space in between should take about the same amount of time as just one of them, but the oven may behave a little differently and heat inconsistently when that full so you may want to turn them and swap them at least once during cooking to balance things out. The formula is an approximation based on how thick the brisket is expected to be at a certain weight.
I was going to wrap them up separately in foil and place them side by side (with space in between).
Thank for the input.
An 8 lb brisket will take significantly longer to cook than two 4 lb briskets. It will take much longer for the center of a large hunk of meat to warm up than it will for a smaller hunk. That’s where cooking times per pound of meat come into play.
Putting two briskets in the oven might slow down cooking a bit compared to one by a small amount, but nothing like doubling the time.
The rule of thumb has no basis in fact. There are two stages in cooking a brisket, getting the meat up to temp and then getting it tender at temp.
Getting any given meat tender at temp will take the same amount of time, regardless of size. Depending on what temperature the meat is at and what type of texture you’re going after, it’ll take anywhere between 2 - 6 hours ish to cook.
Getting the meat up to temp is entirely dependant on the thickness of the meat. Heat transfer goes down as the square of the thickness, meat twice as thick will take four times as long to reach temp.
Two four lb briskets are going to be slightly thinner than an 8lb brisket so they should get to temp slightly faster, maybe an hour less on cooking time. The actual time it will take depends on many small details (including stuff like how tightly you wrap your foil) and the best way is to just cook until you reach your desired level of tenderness and then hold until you’re ready to serve. Brisket can rest for several hours wrapped in an insulated cooler and improves with longer resting times so just start it earlier than you think and hold.