Determination of 4(5)-methylimidazole in carbonated beverages by isotope-dilution liquid chromatography-tandem mass spectrometry

Abstract

The purpose of this study was to develop a method to quantify 4(5)-methylimidazole (4-MEI), a suspected carcinogen, in carbonated beverages by simple sample dilution and isotope-dilution reverse-phase LC-MS/MS. Isotope dilution using hexa-deuterated methylimidazole (d6-4-MEI) was used to quantify native 4-MEI and to assess matrix effects quantitatively. The accuracy of the method was assessed by intentionally fortifying a negative control sample at three doses: low, medium and high (replicates of n = 5 each) with a known amount of 4-MEI. The respective absolute error in each case was 18.7 ± 0.7%, 14.6 ± 2.8% and 21.1 ± 9.7%. Within-day (intra-) and day-to-day (inter-) repeatability, determined as the relative standard deviation by fortifying a negative control sample (n = 5), were 9.5% and 15.4%, respectively. Average ion suppression of d6-4-MEI in beer was 63.9 ± 3.2%, while no suppression or enhancement was seen in non-alcoholic samples. The instrument and method limit of detection were calculated as 0.6 and 5.8 ng ml(-1), respectively. 4(5)-Methylimidazole was quantified in a variety of store-bought consumer beverages and it was found that in many of the samples tested consuming a single can of beer would result in intake levels of 4-MEI that exceed the no significant risk guideline of 29 µg day(-1). Conversely, 4-MEI in the samples was orders of magnitude smaller than the European Food Safety Authority acceptable daily intake threshold value of 100 mg kg(-1) bw day(-1).

Simple and Fast Sample Preparation Followed by Gas Chromatography‐Tandem Mass Spectrometry (GC‐MS/MS) for the Analysis of 2‐ and 4‐Methylimidazole in Cola and Dark Beer

“…The kilned roasted malts used and/or caramel color addition may be the possible sources of the presence of 2‐MeI and 4‐MeI in the dark beers. Our data on the contents of 4‐MeI in the dark beers were also in good agreement with the previously reported values (Klejdus and others ; Cunha and others ; Ratnayake and others ). It has been reported that the 4‐MeI contents in Canada dark beers were in the range of 12.7 to 673 μg/L (Ratnayake and others ).…”

“…Our data on the contents of 4‐MeI in the dark beers were also in good agreement with the previously reported values (Klejdus and others ; Cunha and others ; Ratnayake and others ). It has been reported that the 4‐MeI contents in Canada dark beers were in the range of 12.7 to 673 μg/L (Ratnayake and others ). The 4‐MeI contents in dark beers obtained from Portugal, Spain, and France markets were in the range of 3 to 424 μg/L (Cunha and others ).…”

“…The 4‐MeI contents in Portugal, Spain, and France colas were in the range of 188 to 613 μg/L (Cunha and others ). It has been reported that the 4‐MeI contents in Canada colas were in the range of 9.7 to 641 μg/L (Ratnayake and others ).…”

O subproduto do corante caramelo IV em alimentos pode causar toxicidade?

“…Xu et al (2015) encontraram 4-MEI em refrigerantes e refrigerantes contendo o corante caramelo IV em variações de 0,00013 a 0,00034 mg/mL. Ratnayake et al (2015) observaram variações de 0,0000097 a 0,000641 mg/mL de 4-MEI em diferentes refrigerantes de cola. Cunha et al (2016) avaliaram a presença de 4-MEI em diferentes tipos de café comercializados em Portugal.…”

Preparations of magnetic molecularly imprinted polymer for selective recognition and determination of 4-methylimidazole in soft beverage by high performance liquid chromatography

“…Several methods have been developed to determine 4-MeI based on thin layer chromatography (Rabe et al, 1988), fluorimetry (Wu et al, 2016), capillary electrophoresis (Petruci et al, 2013), or high performance liquid chromatography (HPLC) coupled with ultraviolet light (UV) (Ratnayake et al, 2015). However, these methods require a labor and time-consuming sample pretreatment and have poor sensitivity.…”