HPLC-hrTOF-MS study of copper chlorophylls: Composition of food colorants and biochemistry after ingestion.

Despite the daily consumption of copper chlorophylls (E-141i), the green food colorants in foods high in fats, there is a general need for knowledge regarding their exact composition. Consequently, we have analyzed by HPLC-ESI(+)/APCI(+)-hrTOF-MS the accurate composition of different commercial copper chlorophyll colorants for the first time. Data showed a favored yield of copper pheophytins from a series, while pheophytins from b series are preferentially no complexed with copper. The copper pheophytins present in the food colorants consisted mainly of three structural rearrangements. New fragmentation patterns and structural assignments have been described for several copper pheophytins. During the ingestion of copper chlorophylls, no chlorophyll derivative was present in serum nor urine except a new copper-pyroporphyrin a accumulated in a few livers. In any case, this green additive could represent the ideal food colorant, as most of the copper pheophytins are excreted in the feces showing almost no absorption of copper-chlorophylls compounds.