Development and validation of a duplex real-time PCR assay for the simultaneous detection of three mustard species (Sinapis alba, Brassica nigra and Brassica juncea) in food.
The paper presents a duplex real-time PCR assay for the simultaneous detection of three potentially allergenic mustard species commonly used in food: white mustard (Sinapis alba), black mustard (Brassica nigra) and brown mustard (Brassica juncea). White mustard is detected in the "green" and black/brown mustard in the "yellow" channel. The duplex real-time PCR assay does not show cross-reactivity with other Brassicaceae species including broccoli, cauliflower, radish and rapeseed. Low cross-reactivities (difference in the Ct value ⩾ 11.91 compared with the positive control) were obtained with cumin, fenugreek, ginger, rye and turmeric. When applying 500 ng DNA per PCR tube, the duplex real-time PCR assay allowed the detection of white, black and brown mustard in brewed model sausages down to a concentration of 5mg/kg in 10 out of 10 replicates. The duplex real-time PCR assay was applied to verify correct labelling of commercial foodstuffs.
Department of Analytical Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria; AGES, Austrian Agency for Health and Food Safety, Institute for Food Safety, Department of Molecular Biology and Microbiology, Spargelfeldstraße 191, 1220 Vienna, Austria.
Monika
M
Palle-Reisch
Department of Analytical Chemistry, University of Vienna, Währinger Straße 38, 1090 Vienna, Austria. Electronic address: margit.cichna@univie.ac.at.
Margit
M
Cichna-Markl
AGES, Austrian Agency for Health and Food Safety, Institute for Food Safety, Department of Molecular Biology and Microbiology, Spargelfeldstraße 191, 1220 Vienna, Austria.
Rupert
R
Hochegger
D001937:Brassica / Q000235:genetics*; D018744:DNA, Plant / Q000235:genetics; D005506:Food Contamination / Q000032:analysis*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D031226:Sinapis / Q000235:genetics*
D018744:DNA, Plant
Brassica juncea; Brassica nigra; Food allergen; Multiplexing; Mustard; Real-time PCR; Sinapis alba