Antioxidant activity and phenolic profiles of Sauvignon Blanc wines made by various maceration techniques

Abstract

Background and Aims White wines are typically low in phenolic substances and antioxidant activity, both of which can be increased by maceration with extended skin contact. This study employed five maceration techniques to assess the increase in phenolic substances and in antioxidant activity in Sauvignon Blanc wine. Methods and Results Wines were assessed for the concentration of phenolic substances by a newly developed HPLC method utilising ultraviolet-visible and electrochemical detectors. A significant increase in phenolic substances was observed with some treatments, particularly semi-carbonic maceration (CM) and cryogenic/semi-carbonic maceration (CRCM). The antioxidant activity of the wines was assessed with the oxygen radical absorbance capacity and 2,2′-diphenyl-1-picryhydrazyl assays, and both revealed a six- to sevenfold increase for CM and CRCM over that of the control. Cryogenic maceration alone resulted in wines with a moderate increase in phenolic substances and antioxidant activity, and generally maintained the sensory profile of the control Sauvignon Blanc wines. Conclusions We demonstrated that altering the maceration technique can significantly increase the phenolic profiles of wines and their antioxidant activity. This increase can potentially lead to protection of wine aroma compounds from oxidation and aid in the stability of the wines. Significance of the Study This study demonstrates the ability to produce wines maintaining the quality characteristics of Sauvignon Blanc, while having an increased concentration of phenolic substances. Phenolic substances are associated with wine stability and high antioxidant activity. These techniques provide additional options for oenologists to produce distinctive wines.