Lorenzo writes:

<<Go to primitive Mexico,  above the stove  a massive stone
hearth,  on a wire hangs meat being naturally smoked.>>

Hi Lorenzo,
  I believe I stated nitrites and nitrates as part of the smoking process.
Aside from that, I would think that smoking meats denatures them.  It only
makes sense to me that the more "live" a food is, the shorter the "shelf"
life.  It was probably a necessity at that time in order to have meats more
frequently.  I don't think we need to resort to that now.

Siobhan