Physicochemical, antioxidant activity, and sensory properties of grape juice-herbs extract based isotonic beverages

Abstract

The aim of this work was to develop isotonic drinks free of chemical additives and based on grape juice as a source of carbohydrates, pigments and rich in antioxidants, mixed with herb and spice extracts to improve the taste of the drinks. The color evolution, pH and acidity, sugar content, anthocyanin content, antioxidant activity and sensory properties were analyzed. The results of color evolution demonstrated an increase in color intensity in all samples over four weeks. The determination of anthocyanins revealed the presence of non-acylated and acylated anthocyanins, with malvidin pigments predominating (71.75–73.05%). Antioxidant activity values ranged from 3.97 to 4.92 μmol TE/mL and were positively correlated with anthocyanin content, however anthocyanins were negatively correlated with pH. Sensory evaluation showed that the combination of grape juice with herb and spice extracts promoted the use of natural sources to enrich sports drinks with antioxidants and improve their sensory profile.