Cleaning and sifting

Cleaning is the step that moves a lot across the line between acceptable and not, and for most small producers it is also the step that is skipped entirely because the material arrived looking fine.

What cleaning is for

ASTA's cleanliness specifications are written against categories of physical contamination: insect fragments, whole insects, rodent hair, excreta and foreign matter, each with a maximum by spice. Those specifications are set to meet or exceed the federal defect levels.

Cleaning is the operation that brings a lot inside those limits, or confirms it already is. It is not decorative.

What you can remove and what you cannot

Sifting, winnowing and hand sorting will take out stones, stems, chaff, and gross foreign matter. Those are the visible categories and they are genuinely within reach of a small operation working in daylight on a light-colored surface.

What cleaning will not touch is anything microbial, and it will not touch adulteration. A cleaned lot can still carry Salmonella and can still be the wrong species with a pigment added. Different failures, different controls.

Sifting as a grading step

Sifting does a second job worth having deliberately rather than accidentally: it narrows the particle size distribution. Removing the fines and the oversize from a ground lot improves flow, improves how it sifts in the customer's jar, and reduces the segregation that pulls blends apart.

Keep the screens and record which you used. It becomes part of the product specification whether you write it down or not.

Between materials

Everything that touches a strong material carries it to the next one. Screens and funnels in particular hold residue in places you cannot see, and cumin and asafoetida will announce themselves in whatever follows.

Work mild to strong through a session, clean properly at the end rather than between each, and keep a separate set of screens for the materials that will not let go.

References