Currently, there is a clear tendency to incorporate natural ingredients into food and pharmaceutical formulations. Besides being well-accepted by consumers, these ingredients have less adverse side effects than their artificial counterparts. The pomegranate processing industry produces large quantities of by-products that are discarded as bio-residues, despite containing bioactive compounds. Accordingly, the epicarp of two pomegranate varieties (Mollar de Elche and Purple Queen) was tested as a potential source of bioactive compounds with food application. The phenolic profile was identified by HPLC-DAD-ESI/MS, revealing fourteen phenolic compounds in both varieties (Purple Queen showed also three anthocyanins), with punicalagin isomers as the major compounds. Nonetheless, Mollar de Elche presented greater antioxidant and antibacterial activities. Despite this result, Purple Queen was selected to be tested as a new natural colouring and functionalizing ingredient in a Brazilian pastry product. The incorporation of the selected extract maintained the nutritional profile and provided a higher antioxidant activity compared to the traditional product. In this way, this work confirmed the possible use of pomegranate epicarp as a natural ingredient in the food industry, conferring dyeing and functionalizing effects, and anticipating a possible valorisation of this bio-residue.
Keywords: Punica granatum L.; bioactivity; food application; pectin; phenolic compounds.