Rhodamine B in spices determined by a sensitive UPLC-MS/MS method

ABSTRACT

Rhodamine B (RhB) is a banned food additive and has been classified as illegal colourant. Therefore, the risk of RhB contamination should be strictly monitored. In this study, a sensitive UPLC-MS/MS method was applied to monitor RhB in 292 various spices such as chilli, pepper and tomato products. The results showed 22.7% of chilli powder samples, 18.5% of pepper powder samples, 11.1% of chilli oil samples and 9.1% of pepper oil samples were contaminated with RhB. Chilli powder contained RhB up to 44,935 μg/kg with an average of 743 μg/kg, pepper powder up to 65.9 μg/kg with an average of 4.1 μg/kg, chilli oil up to 14.6 μg/kg with an average of 1.0 μg/kg and pepper oil up to 1.1 μg/kg with an average of 0.2 μg/kg, respectively. Considering the common consumption of chilli products and pepper products by so many consumers, RhB exposure is significant and should be decreased.

KEYWORDS:

• Rhodamine B
• spices
• UPLC-MS/MS
• pepper
• chili powder
• tomato product
• illegal colorant

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Key Research and Development Plan of Shaanxi Province [No.2017SF-379]; Natural Science Basic Research Plan inShaanxi Province of China [No.2017JM8049]; Scientific Research Program of Shaanxi Provincial Education Department [No.18JS109].