ISO 18731:2025

Overview

ISO 18731:2025 - Spices and condiments: Seasoning oil of Zanthoxyli pericarpium - Specification - defines quality, safety and labelling requirements for seasoning oil produced from Zanthoxyli pericarpium (prickly ash / Sichuan pepper) fruits. The standard standardizes sensory, physicochemical and contaminant criteria, test methods (including annexed procedures), and packaging, storage and transport rules to support consistent production, testing and international trade.

Key Topics and Requirements

• Scope: Applies to seasoning oil of Zanthoxyli pericarpium produced by extraction, cold pressing, supercritical CO2 or dilution into vegetable matrix oil.
• Sensory requirements: Appearance (clear oily liquid), colour under sunlight, characteristic Zanthoxyli flavour and taste; free from foreign flavours/tastes.
• Physicochemical limits:
  • Acid value (KOH): max 3.0 mg/g (Grade I & II) - ISO 660
  • Peroxide value: max 20.0 meq/kg - ISO 3960
  • Moisture: max 0.8 g/100 g - ISO 662
  • Amides (key active compounds, e.g., sanshools): Grade I min 5.0 mg/g; Grade II min 4.0 mg/g - tested by Annex B (UV spectrophotometry)
  • Residual solvents: testing by Annex C or ISO 9832; values < 10 mg/kg are regarded as “not detected.”
• Contaminant & toxin limits:
  • Lead ≤ 0.08 mg/kg, arsenic ≤ 0.1 mg/kg (CXS 193)
  • Benzo[a]pyrene ≤ 2.0 µg/kg - ISO 15302
  • Total aflatoxins ≤ 10 µg/kg - ISO 16050
• Packaging & marking: Sealed, inert containers; labelling must include product (botanical name), batch, producer, country, packaging date, shelf life, grade/type and reference to the standard when applicable.
• Storage & transport: Dry, ventilated, avoid direct sunlight and separation from toxic/odorous goods (Annex A).

Applications and Users

ISO 18731:2025 is intended for:

• Producers and packers of Zanthoxyli pericarpium seasoning oil for product specification, quality control and grading.
• Food testing laboratories using the standard’s annexed analytical methods (UV spectrophotometry for amides; headspace/GC or ISO methods for residual solvents).
• Importers, exporters and retailers seeking compliance with international safety and labelling expectations.
• Regulators and standards bodies harmonizing trade requirements for spices and condiments.

Practical uses include product development, batch release testing, supplier specification, trade documentation and risk-based compliance with pesticide, mycotoxin and contaminant limits.

Related Standards

Referenced standards and resources used by ISO 18731:2025 include:

• ISO 660, ISO 662, ISO 3960, ISO 9832, ISO 15302, ISO 16050
• CXS 193 (Codex General Standard for Contaminants) and the Codex Pesticide Residues in Food online database

Keywords: ISO 18731:2025, seasoning oil of Zanthoxyli pericarpium, Zanthoxyli pericarpium oil specification, spices and condiments standard, amides testing, residual solvent limits.