Studies into plant pigments from maqui (Aristotelia chilensis (Mol.) Stuntz) and jagua (Genipa americana L.) fruits as natural dyes

The discovery of novel plant-based pigment sources is still of utmost interest to the food industry. For instance, carmine dyes are characterized by exceptional bright and stable colors and were until recently used as a natural alternative for red hues. However, due to their insect-based origin, they are now disparaged as allergenic and nauseating as well as for being non-vegetarian, non-vegan, non-halal, and non-kosher. Revealing outstandingly high anthocyanin contents, the intensely dark colored maqui (Aristotelia chilensis (Mol.) Stuntz) berry might represent an interesting novel red pigment alternative. Besides red colors, the sole truly natural blue pigment currently approved for food use is phycocyanin from the cyanobacteria Spirulina that, however, is highly susceptible to heat, light, and acid due to its proteinaceous nature. Thus, a natural substitute is urgently needed for blue hues. Blue pigments based on polymerization reactions of the iridoid genipin contained in the unripe jagua (Genipa americana L.) fruit with primary amines might represent a novel blue color source.

The present doctoral thesis provides comprehensive insights into the great potential of yet underutilized maqui berry- and jagua fruit-derived pigments as novel natural alternatives for red and blue food coloration, respectively. Detailed analyses on the fruit composition of maqui followed by investigating the color stability of maqui anthocyanins were carried out to assess the potential of maqui berry for food applications. The still limited number of reports about color stability of the jagua-derived blue colorant named Jagua blue was complemented by an in-depth study of its color characteristics, and additionally comparing the results with those obtained for approved blue food colorants.