Oops, somehow I missed your thread and the mentions from Jake and Chopsaw. I like the texture of hot packed pork, game and beef over raw packed. For chicken and turkey the differences are more subtle. It's good you are doing both methods and can test which one you prefer.
Cold packed meats take less time to prep but I like the ability to season meats when I par-cook and hot pack them. One of the main reasons I like hot packed meats is the meat shrinks less, and your jars are full of broth. All of the canning sources call for "no added liquid" when using the raw pack method, which means you often wind up with meat above the broth level. The reasoning behind this rule is simply... when testing was done, raw pack meats didn't receive any additional liquid. Fast forward 50 or 60 years and we have enhanced meats, especially turkey and chicken. No testing was done on brined or enhanced meats but the canning experts seem to have forgotten that.
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So, when I do raw pack chicken (almost all my meats are in the 1.5 pint jars) I add some liquid. Bending the "no added liquid" rule, I add 3 tablespoons of broth. If I buy the enhanced chicken breasts from Sam's Club, I can reduce the broth to 2 tablespoons. For some additional richness I'll add one or two boneless thighs to the jars. I put a healthy pinch of black pepper in the jars, then add meat, broth, a second pinch of pepper, and 1/2 teaspoon canning salt. Then work out any air bubbles with the Ball tool. With these jars my processing time is 90 minutes, at 13 psi (because I'm at 5400' elevation)
Now, here is where my method
could produce slightly different results.... Back to the safety testing of yesteryear.... the 1.5 pint jars were not used in testing, only pints and quart jars were used. So, the rule of thumb is to process 1.5 pint jars using times for quart jars. Common sense would tell me I'm likely over-processing a little bit, and the additional fat from adding thighs probably helps here. Trying to shorten processing times would be a slippery slope I don't want to mess around with.