Auramine O in foods and spices determined by an UPLC-MS/MS method

ABSTRACT

Auramine O (AO) is a banned food additive and has been classified as an illegal colourant. Therefore, the presence of AO in food should be strictly monitored. In this study, a sensitive UPLC-MS/MS method was applied to monitor AO in 211 food and spice samples. The optimised separation was achieved with a mobile phase consisting of 100 mM ammonium formate at pH 2.9 and acetonitrile, reversed-phase CORTECS T3 column (2.7 µm, 2.1 × 100 mm) operated at 40ºC with a gradient time of 20.0 min (0–95% methanol) at a flow rate of 0.3 mL/min. Limit of detection (LOD) and limit of quantification (LOQ) of the method were 0.1 μg/kg and 0.5 μg/kg, respectively. The results showed that 27.0% of samples were contaminated with AO. Considering the common consumption of sour bamboo shout and turmeric powder by so many consumers, AO exposure is significant and should be decreased.

KEYWORDS:

• Auramine O
• synthetic food colour
• food
• spice
• solid phase extraction

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research is funded by Graduate University of Science and Technology under grant number GUST.STS.ĐT2017-HH06.