Physicochemical, functional and sensory characteristics of a filtering infusion based on lemon balm leaves (Melissa officinalis L.) and orange peel (Citrus sinensis (L.) Osbeck)

Melissa officinalis L., a medicinal herb, is a source of a large number of bioactive compounds, as well as orange peels, mainly owing to phenolic compounds widely studied for their biological properties. The present investigation focused on studying the physicochemical, sensory and biological characteristics of lemon balm leaf and orange peel infusions. The analysis was carried out through the quantification of total phenolic content (TPC), antioxidant activity by DPPH and ABTS. In addition, the optimization of the best infusion was assessed by response surface methodology (RSM) and analysis of variance (ANOVA). The results showed a TPC between 4.50-4.80 μg GAE/ mL, an antioxidant activity in the range of 53-74 % by DPPH and 73-83 % by ABTS. On the other hand, the RSM reported the optimal conditions of the infusion with the best sensory acceptability and desirability resulted from combining 150 g of lemon balm leaves with 60 g of orange peel. Nevertheless, the extracts showed limited antioxidant activity, less than 80 % inhibition and with halos of less than 8 mm by disk diffusion.