- Identity
- HPTLC fingerprint to confirm the Glycyrrhiza species and root part, since glabra, uralensis and inflata are traded under the same common name.
- Glycyrrhizin assay (HPLC)
- Glycyrrhizin (glycyrrhizic acid) by HPLC; for DGL, the maximum glycyrrhizin left. US food use limits are set by glycyrrhizin content of the finished food, so the figure matters for formulation.
- Heavy metals
- Lead, arsenic, cadmium and mercury by ICP-MS against the buyer's limits and any Prop 65 exposure targets.
- Microbiology
- Total plate count, yeast and mold, E. coli and Salmonella. Raw cut herb and powder carry more microbial load than extracts and may be steam treated.
- Pesticide residues
- Multi-residue screen by GC-MS/MS and LC-MS/MS, required for organic claims and commonly asked for on conventional lots.
- Ash and physical tests
- Total ash and acid-insoluble ash, loss on drying, mesh size, and residual solvents for extracts made with ethanol.