Specification first
Everything else is quoted against it.
A lot that behaves differently on the line costs more than the few cents you saved buying it.
Production is calibrated around a material behaving the same way every time. Granulation and moisture that drift between lots show up as yield problems, and they rarely get traced back to the ingredient.
So everything starts with a written specification and a sample. Both sides agree what is being bought before anything is produced, which removes most of the disputes this trade generates.
Documentation does the rest. Lot coding and paperwork that travels with the shipment mean a question months later has an answer, which matters to any buyer with a compliance obligation of their own.
Everything else is quoted against it.
Test it on your line, not on a promise.
No health claims, and your labelling stays your responsibility.
Send the grade, the volumes and the format. Free, and within one business day.