Study on the non labeled synthetic colorants were detected in natural food pigments and condiment

ObjectiveThe method of high performance liquid chromatography （HPLC） was developed to study the detection of synthetic colorants in natural pigments and condiment.MethodsThe analytes were extracted by direct ultrasonic extraction with water. The analytes were separated on a ShimNex C18 column （4.6 mm×150 mm， 5 μm） using a mobile phase comprising methanol and 0.02 mol/L ammonium acetate solution. The analytes were detected by HPLC and quantified by external standard method.ResultsThe good linear relationship of peak area was observed for the 8 synthetic colorants used frequently with correlation coefficients ≥0.999 1 in the concentration range of 0.1-25 μg/mL， and the average recoveries of the blank samples at different added levels ranged from 84.7% to 105.3% with RSDs of 0.8%-5.7%. Application of the method， synthetic colorants were detected in condiment claimed to add natural pigments， as well as in radish red and betacyanin natural pigment raw materials， which were ponceau 4R， sunset yellow and amaranth，and more than two synthetic colorants were detected simultaneously in samples. Showed that synthetic colorants were generally detected in the raw materials of natural colorants， the situation of added low doses or multiple colorant compounds existed in some natural colorant raw materials.ConclusionThe established methods is fast and reliable， and the suggestions and references for enterprises are provided to avoid risks， using colorants in compliance and effective supervision of relevant functional departments. At the same time， it is great practical significance for ensuring food safety.