Hibiscus rosa-sinensis as flavoring agent for alcoholic beverages

The present work is an evaluation of the chemical composition of the aroma and the sensorial characters of a beer flavored with Hibiscus rosa-sinensis flowers. Moreover, the total polyphe-nol, flavonoid and anthocyanin contents and the antioxidant activity of the plant materials and beers were assessed. A comparison with a liqueur flavored with the same hibiscus flowers was also per-formed. Non-terpene derivatives constituted the main class of components of the aroma of both samples, representing 96.4% of the whole volatilome in the control beer and 99.0% in the hibiscus one. Among this class, esters were the most abundant compounds, being significantly higher in the treated sample (77.6%) than in the control (68.4%), followed by the alcohols (20.9% in control beer and 18.8% in hibiscus beer). From a sensorial point of view, the control beer was characterized by malty and hoppy notes, attributable to the noticeable content in myrcene and α-humulene in its headspace, while in the hibiscus beer, floral and fruity notes, typical of esters and alcohols, pre-vailed. The polyphenol content was significantly higher in the treated beer (143.96 mg/g) than in the control, as well as the total flavonoids and the total anthocyanins, and, consequently, the antioxi-dant activity (DPPH-assay).