Review of methods for the analysis of culinary herbs and spices for authenticity
Abstract:
This report reviews current analytical methods for verifying the authenticity of dried culinary herbs and spices, focusing on deliberate adulteration rather than accidental contamination. Stakeholder engagement identified oregano and black pepper as the commodities of greatest concern, followed by chilli powder, saffron, paprika and turmeric, with common fraud types including substitution, dilution and concealment. A wide range of food authenticity testing methods are used, including spectroscopy (near-infrared (NIR) and Fourier-transform infrared (FT-IR)), DNA-based techniques such as PCR and next-generation sequencing (NGS), and mass spectrometry approaches (GC-MS, LC-MS). Rapid spectroscopic screening techniques, particularly NIR and FT-IR, are increasingly favoured as non-destructive, cost-effective tools within a tiered testing strategy, where suspect samples are confirmed using complementary analytical methods. Key challenges include limited certified reference materials, restricted access to authenticity databases, and inconsistent sampling strategies. Many laboratories rely on a weight-of-evidence approach, combining microscopy, spectroscopy and molecular testing. The report recommends improved reference databases, method validation, training and collaboration to strengthen herb and spice authenticity testing, support regulatory enforcement, and enhance detection of economically motivated adulteration (EMA).
Date:
2024
Keywords:
Herb and spice adulteration, Food authenticity testing, Spectroscopy, DNA-based detection, Mass spectrometry, Rapid screening methods, Certified reference materials, Food authenticity databases, Weight-of-evidence approach, Regulatory enforcement
