@Bzelbob - Likely correct. You can catch a QA problem if you do it before they leave and are distributed but reporting delays make pulling something that is in mass-distribution in time to matter nearly impossible.

Witness all the crazy from the CDC recently with regard to onions that are presumably contaminated with salmonella. Ok, so you issue the "throw it away" recommendation but by the time you detect where it came from and what's going on most of them have already gone down someone's gullet.

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