Presence of Undeclared Food Allergens in Cumin: The Need for Multiplex Methods

Beginning in the autumn of 2014, millions of dollars of food and over 675 products were recalled in the United States due to the presence of undeclared peanut, attributed to cumin used in the manufacture of the products. Initial analyses also indicated the presence of almond. Subsequent research showed that the presence of peanut and almond did not fully explain the analytical results for the cumin samples. Using a combination of mass spectrometry, DNA-based methods (i.e., PCR and Sanger DNA Sequencing), microscopy, and antibody-based technologies (i.e., ELISA, Western blot analysis, and a novel xMAP multiplex assay) the presence of peanut was confirmed. Screening for secondary sources of adulteration (e.g., tree nuts, mahieb, peach, and cherry) supported the assessment that the cumin contained multiple contaminants. These results demonstrate the limitations of single analyte-specific assays and the need for orthogonal multiplex methods to detect food allergens irrespective of varietal or other differences.