Spice moisture is the water content of dried herbs and spices, a standard analytical parameter that governs microbial stability, caking behaviour and shelf life throughout storage and trade.
In trade practice
Moisture is measured by oven-drying or near-infrared methods at intake inspection and again before dispatch, with results recorded on the certificate of analysis. Limits vary by product: leafy herbs are typically more sensitive to moisture uptake than whole seeds, and packaging in moisture-barrier materials is specified accordingly. High moisture at intake is a common cause of mould development and clumping during transit. ISO and ASTA methods are referenced in many trade specifications to ensure comparable results between supplier and buyer laboratories.
In a specification
A spice specification states the maximum moisture content as a percentage on an as-is basis, the test method to be used and the sampling plan applied at goods receipt.