Evaluation of bioactive phenolic compounds and antioxidant activity of Cabernet Sauvignon wines during winemaking

Bioactive phenolic compounds of red wines from Cabernet Sauvignon, V. vinifera red variety, were determined using high-performance liquid chromatography coupled to diode array detector (HPLC-DAD) [1]. Spectrophotometric analyses were performed at the following wavelength: 280 nm (total phenols), 420 nm (browning degree), 520 nm and 620 nm (anthocyanins) nm with a UV-VIS spectrophotometer. Antioxidant activity of wines was determined as a radical scavenging ability following the procedure described by Brand-Williams et al. (1995) [2]. Wines were produced by different maceration time (3, 6 and 9 days) in order to study its influence on the phenolics extraction during winemaking. A total of 19 bioactive phenolic compounds were identified and quantified in wines. Malvidin-3-glucoside was the main anthocyanin in wines, ranging from 251 to 466 mg/L, while caftaric acid was the predominant cinnamic acid derivative, ranged from 94.1 to 166 mg/L. Anthocyanins were observed to be present in the highest content after 6 days of maceration (858 mg/L), while phenolic acids and (+)-catechin content was highest 9 days after the skin maceration (523 and 375 mg/L, respectively). Cabernet Sauvignon wines showed relatively high antioxidant activity (on average: 115 mg/L, Trolox equivalents)