Blue wine, a color obtained with synthetic blue dye addition: two case studies

Blue wine, recently appeared on the French market, is part of the effort made by winemakers in creating new and attractive wine, while maintaining traditional manufacturing processes. According to the labels on the bottles, the blue wine prides itself on being a natural wine, whose blue color is also obtained in a natural way by means of a very particular wine-making process. This study reports first analyses carried out on two blue wines to determine the origin of the blue color. The results show that a well-known coloring food additive was used in the wine and identified as Brilliant Blue FCF by UV–Vis spectroscopy and high-resolution mass spectrometry. The amounts of Brilliant Blue FCF were assessed in the two wines by high-performance liquid chromatography coupled to UV–Vis spectroscopy and found to be 8.62 ± 0.04 mg L −1 and 5.46 ± 0.01 mg L −1 in Vindigo and Imajyne wines, respectively. Such addition was, however, not specified by the winemakers.