Yes, it is legitimate, in certain cases, to retest, thereby requalifying a raw material past its expiration date. Typically, industry may assign a six-month to one-year extension based on the retest results.

The product specification must still be met, and factors that may change over time must be assessed. These factors may include potency level, microbiological levels, polymerization, rancidity levels, and organoleptic properties. Many ingredients which inherently have a long shelf life are given expiration dates to trigger analysis for these very factors.