A DNA Metabarcoding Workflow to Identify Species in Spices and Herbs

Area of Science:

• Food Science
• Molecular Biology
• Analytical Chemistry

Background:

• Herbs and spices are frequently adulterated with undeclared species.
• DNA-based methods are the preferred tools for detecting such adulteration.

Purpose of the Study:

• To evaluate the performance of a commercial DNA metabarcoding workflow for authenticating herbs and spices.
• To analyze the authenticity of commercial spice and herb samples using this workflow.

Main Methods:

• The Thermo Scientific™ NGS Food Authenticity Workflow was used for DNA metabarcoding.
• Specificity was assessed using pure spice and herb samples.
• Sensitivity was evaluated through spikings down to 1% (w/w).
• 272 commercial samples from Asian and European markets were analyzed.

Main Results:

• The workflow correctly identified all tested species, often to the species level.
• A limit of detection of 1% (w/w) was confirmed, even in complex mixtures.
• 78% of commercial samples were compliant; the remaining 22% contained undeclared species, some potentially allergenic or toxic.

Conclusions:

• The NGS Food Authenticity Workflow is effective for identifying plant species in herbs and spices, including in mixtures.
• The workflow is user-friendly, facilitating data interpretation and implementation in testing laboratories.
• It successfully detected undeclared species in commercial samples, enhancing food safety.