Spice grinding is the mechanical milling of whole or dried spices into powder using hammer, pin or plate mills, where mill speed, feed rate and screen mesh size determine the final particle size and aroma retention.
In trade practice
Mill operators select screen mesh to meet the buyer’s particle size specification and control feed rate to avoid heat build-up that degrades volatile oils. Sieve analysis is performed on each batch and results are recorded in the quality control log. Common errors include over-milling, which generates excessive fines, and insufficient cooling, which causes aroma loss. Cryogenic grinding is used as an alternative when aroma preservation is critical.
In a specification
A purchase contract or product specification for ground spice will reference the required mesh pass percentage, the milling method where relevant, and the maximum temperature permitted during processing.