Freeze drying is NOT the same as simple dehydration.
Freeze drying involves two steps:
1) Freezing: That's simple enough.
2) Drying : This involves sublimating the moisture from whatever you are freeze-drying by exposing it to a vacuum. Home freeze drying appliances are available but are not exactly cheap
Maybe simple dehydration might be a better alternative.
Yeah I've powdered and capsuled san pedro and eaten it. The thing nobody tells you is...have you ever dropped san pedro into water? It blows up to ten times it's original volume and all this deep brown scummy shit floats to the surface - so imagine that happening in your stomach and what kind of nausea that causes.