A shipment that passed every quality check at origin can still lose grade in a buyer's own warehouse if it's stored wrong. Whole cassia, cloves, nutmeg and mace are more forgiving than ground spice, but they can still go off. Four things decide how long a lot keeps its grade after arrival.
The first and biggest is humidity. Spice slowly takes moisture back in from the air, so for most whole spices, keeping storage below roughly 60% relative humidity matters more than temperature. Second, keep the original packaging sealed until you use it. Every time a bag is opened and closed, moisture and oxygen get in.
Third, light and heat slowly break down the essential oil. Cool, dark storage protects the aromatic compounds, and those decide quality far more than appearance does. Fourth, first-in-first-out stock rotation matters more for whole spice than most buyers assume. Oil content, and with it flavor strength, declines slowly but steadily, counting from the day of drying and not the day of packing.
None of this is complicated, but we get asked about it often enough to spell it out. The certificate of analysis we issue describes the product at the point of shipment. How it's stored in your warehouse after that affects what you end up with.
