Others may disagree, but I'd be concerned about that. The broth may be thin, but the largest container that's actually been tested for broth is a quart. Fruit juice is acidic and I'm a bit more relaxed with that, as a high acid product it may spoil or make you sick, but it probably won't kill you. Meat broths, however, can harbor botulism and that CAN kill you. I wouldn't even want to guess at the timing for a half gallon, and there are no instructions for timing on larger sizes than a quart.

Will half gallons even fit in your pressure canner? Meat broths do have to be pressure canned, and they would fit in my All American but not the smallest Presto/Mirro types, I don't think.

Anyway, if you decide to forge ahead, I would:

A. Overestimate the time, as broth isn't going to get "mushy" or other compromised if it's over processed; and

B. Be very certain to boil that broth 10 minutes after you open it and before you consume it, to add a layer of safety.

Good luck, whatever direction you decide to take.

Annie

Second what Annie said. Whatever you decide to do, there are a lot of differences between high-acid foods and low-acid foods and broth in a half-gallon jar would be a lot more dangerous than juice in a half-gallon jar.