Hibiscus sabdariffa (Roselle) Extracts and Wine: Phytochemical Profile, Physicochemical Properties, and Carbohydrase Inhibition

摘要

Three varieties of Hibiscus sabdariffa were analyzed for their phytochemical content and inhibitory potential on carbohydrate-digesting enzymes as a basis for selecting a variety for wine production. The dark red variety was chosen as it was highest in phenolic content and an aqueous extract partially inhibited alpha-glucosidase (maltase), with delphinidin 3-O-sambubioside, cyanidin 3-O-sambubioside, and 3-O-caffeoylquinic acid accounting for 65% of this activity. None of the varieties significantly inhibited alpha-amylase. Regarding Hibiscus sabdariffa wine, the effect of fermentation temperature (20 and 30 degrees C) on the physicochemical, phytochemical, and aroma composition was monitored over 40 days. The main change in phytochemical composition observed was the hydrolysis of 3-O-caffeolquinic acid and the concomitant increase of caffeic acid irrespective of fermentation temperature. Wine fermented at 20 degrees C was slightly more active for alpha-glucosidase inhibition with more fruity aromas (ethyl octanoate), but there were more flowery notes (2-phenylethanol) at 30 degrees C.