A bit of an old post, but my peach trees are loaded this year and I may get enough to make some brandy, after we make jam and freeze some for pies and cobblers. In doing a bit of research on the cyanide factor, the noyaux (kernel, pronounced nwa-yo) is what contains amygdalin, which your body converts to cyanide.
One
reference states that a 150 lb/68 kg person could eat up to a kg of noyeax before it becomes lethal. It further states that roasting the whole pits at 350F/176C for 10-15 minutes neutralizes most of the amygdalin and makes the pits easy to crack. You can then roast the noyaux for 10 more minutes to completely neutralize the amygdalin.
So I think what I'll do is to let the peaches get slightly over-ripe, crush them and remove the pits. The roast a few pounds of the pits, crack them open, roast the noyeax, and add them to the fermentation.
Interestingly, almond extract is made from the noyeax of apricots.