Many years ago a bacon factory, that no longer operates was caught out repackaging hams that had expired the use by date. The hams were being put through an acidic acid wash [vinegar]. Repackaged and a new use by date being applied, extending the use by date.
One can never be sure if the product you buy is 100% safe.
-- Edited by Phillipn on Saturday 22nd of December 2018 09:21:13 PM
Lived in a South Australian country town some years ago, the lady owner of the local supermarket instructed staff to wipe small goods that were getting "slimy" with cloth soaked in vinegar, then back into the display cabinet.