I know safety is paramount with canning, and best answer is always to find a trusted recipe. But that's obviously not possible for every conceivable food one might want to can. Besides, trusted recipes came from somewhere (and work even though for example exact pH of fruit varies), and there are plenty of companies out there canning all kinds of things. So:
Given pH, jar/bottle size, and hot vs cold pack, can I determine whether boiling water or pressure canning is safe and what processing time is necessary? What if I err on the side of safety and assume pressure canning is required - then can I determine a time?
Is there some sufficiently long processing time of pressure canning that will make anything safe, or at least anything meeting some broad criteria? (The idea being not to have to measure pH.)