How to Read a Certificate of Analysis (COA) for Spices

A Certificate of Analysis is the single most important document in any spice trade transaction. Yet many buyers glance at a COA without knowing what to look for — and end up accepting documents that would not pass scrutiny at their destination country's port. This guide teaches you to read a COA like an experienced trade professional.

What a COA Is (and What It Is Not)

A COA is a document issued by a laboratory confirming the test results for a specific batch of product. It is not a quality guarantee from the supplier — it is an objective measurement from a testing facility. A COA is only as reliable as the laboratory that issued it and the sample it was tested on.

The 7 Things to Check Immediately on Any Spice COA

1. Laboratory Name and AccreditationThe lab must be NABL-accredited (India's National Accreditation Board for Testing and Calibration Laboratories) or hold ISO/IEC 17025 certification. Look for the accreditation number on the COA — typically printed in the header or footer. A supplier's own in-house lab COA carries no independent authority and should not be accepted as primary documentation.

2. Sample Reference and Batch/Lot NumberThe COA must reference the exact batch or lot number you are purchasing. A generic COA issued for a previous shipment — even of the same product — is not valid for your consignment. Insist that the batch number on the COA matches the batch number on the packing list.

3. Test DateFor spices, the COA should be dated within 6 months of the shipment date. Volatile oil content, moisture, and microbiological status all change over time. An 18-month-old COA is commercially and legally worthless.

4. All Parameters PresentA genuine, complete COA for a spice export covers: moisture content, total ash, acid-insoluble ash, volatile oil content, relevant active compound (curcumin for turmeric, piperine for pepper, etc.), aflatoxin panel (B1, B2, G1, G2), heavy metals panel (Lead, Arsenic, Cadmium), pesticide residue multi-panel, and microbiological parameters (TPC, Salmonella, E. coli, Yeast & Mould). A COA showing only 3–4 parameters is incomplete.

5. Test Methods ListedEach parameter should state the method used — e.g., "Moisture: AOAC 931.04" or "Curcumin: HPLC." The method tells you whether the result is internationally recognised and comparable to other labs' results.

6. Result vs. Specification ColumnMost professional COAs show three columns: the parameter, the test result, and the specification limit. Verify that every result falls within the stated specification. If any result shows "Fail" or falls outside the limit, the lot should be rejected or re-tested.

7. Authorised Signature and Laboratory StampThe COA must be signed by the testing analyst and/or laboratory director and carry the laboratory's official stamp or seal. An unsigned, unstamped COA is not a valid document.

Red Flags That Should Prompt Rejection

• Lab is not NABL or ISO 17025 accredited

• Batch number does not match your purchase order

• COA dated more than 6 months ago

• Fewer than 8–10 parameters tested

• No test methods listed

• Pesticide results shown only as "within limits" without individual compound listings

• Supplier is reluctant to share the COA before payment

Crestrock Global provides full NABL-accredited COAs for every shipment — with all parameters, all test methods, and batch-specific references — before container sealing. Contact us to see a sample COA for any of our products.