Don't understand your question about weighing your food
unless you are trying to ascertain the weight to establish
protein content. In that case, I would think you would want
to weigh it before you dehydrate it as the dehydration
process removes the water, would not remove protein. You
don't weigh your other food after cooking do you, so why
would you do so in this case?
Just my 0.02 cents worth . . .