Here is the official AAFCO definition for "natural" as the term relates to pet food:
"NATURAL... A feed or ingredient derived solely from plant, animal or mined sources, either in its unprocessed state or having
been subjected to physical processing, heat processing, rendering, purification extraction, hydrolysis, enzymolysis or fermentation,
but not having been produced by or subject to a chemically synthetic process and not containing any additives or processing aids that
are chemically synthetic except in amounts as might occur unavoidably in good manufacturing practices."
