Potential valorization of Cornelian cherry (Cornus mas L.) stones: Roasting and extraction of bioactive and volatile compounds

Abstract

This study aimed to characterize the antioxidant potential, bioactive and volatile compounds of the stones from fruits of Cornus mas. Both fresh and roasted stones show a high antioxidant potential (166.48-509.74 μmol TE/g dw stones), which significantly depends on the cultivars. The roasted stones preserved 43.6% (DPPH; 'Raciborski') to 97.2% (FRAP; 'Alesha') of the antioxidant activity of the non-roasted stones. In the stones, two iridoids and ellagic acid were determined. During roasting, loganic acid remained stable, whereas cornuside was completely degraded. The analyses showed a 30-fold increase in the concentration of ellagic acid and in the formation of two of its derivatives. The major aroma compound of the roasted stones was furfural, but we also identified 18 pyrazine derivatives. This study is the first attempt to valorize Cornelian cherry stones via roasting. The roasted stones can be a coffee substitute, or aromatic and bioactive additions to cereal coffees.

Keywords: Antioxidants; Cornus mas L.; Iridoids; Roasting; Stone; Volatile compounds.