[Sca-cooks] Re: Sca-cooks diges - Freeze-drying

[Stefan li Rous]

Devra the Baker said:
> Peruvian Indians are reported (no, I don't remember the source) to have used
> this technique on potatoes.  They would leave the taters outside at night to
> freeze, and then tread on them to push out the liquid.  (Ow! OW!  Think of
> stepping on pebbles!  They must have had the hardest feet!)

I don't believe that is "freeze-drying". That is simply using the
freezing process to break down the potatos, a tenderizing process.

Neither do I believe what Gunthar described was freeze-drying, at
least not in the modern sense. In freeze-drying you first freeze
the food item, or the animal if you are doing this for mounting, and
then you must put the item in a vacuum chamber and pull a vacumm on
it. In a vacuum the ice changes directly from a solid state to a
gaseous state. This avoids the liquid state which is what makes things
squishy.

Perhaps high enough in the Andes you can get the water in the frozen
potato to go directly from a frozen state to a gaseous state, but
you wouldn't be "pushing out the liquid". If you did manage to get
a somewhat freeze-dried potato by this method, it would certainly
be easier to tread them into a mush or powder than if they were frozen.

--
THLord  Stefan li Rous    Barony of Bryn Gwlad    Kingdom of Ansteorra
Mark S. Harris             Austin, Texas         stefan at texas.net
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