JRC-developed methods for detection of adulteration of spices recommended for standardisation

Herbs and spices are high-value products. Their high price and complex supply chains increases the risk of adulteration by either completely replacing the spice in question or by adding lower value ingredients. A coordinated control plan executed in 2019-2021 found that 17 % of cumin, curcuma, paprika/chilli, pepper, oregano,  and saffron showed some sign of adulteration, oregano being the most vulnerable commodity to suspicious practices.

The JRC has developed a series of measurement methods to detect and quantify adulteration of these spices.  The methods are based on DNA testing (quantitative polymerase chain reaction): in a first step, the spice is screened for the presence of other plants and in a second step the amount of this admixture is quantified. The methods have been tested at the JRC and found sufficiently accurate for the detection and quantification of adulteration.

In a second step, thirteen of these methods with their related test materials were sent to 25 different European laboratories to investigate how much results from the various laboratories differ. Marc Behr, one of the scientists who developed the methods says: “There can be small details that have a large influence on the results. Only testing a method in different laboratories can really show that a method can also deliver correct results in other laboratories”.

The results of this comparison were presented at the recent meeting of the Technical Committee for Food Authenticity of the European Committee for Standardisation (CEN/TC460). The committee welcomed the work performed by the JRC and invited the JRC to make a formal proposal for a new project in this CEN Technical Committee. If the proposal is accepted by the European Standardisation bodies, the methods will be developed into a Technical Specification. In this way, the methods will be available to laboratories world-wide, especially in Member States of the European Union, and allow them to detect fraudulent admixture of low-value ingredients to herbs and spices.