The Antioxidant Potential of White Wines Relies on the Chemistry of Sulfur-Containing Compounds: An Optimized DPPH Assay.
The DPPH (2,2-Diphenyl-1-picrylhydrazyl) assay is an easy and efficient method commonly used to determine the antioxidant capacity of many food matrices and beverages. In contrast with red wines, white wines are poorer in antioxidant polyphenolics, and the more hydrophilic sulfur-containing compounds in them may contribute significantly to their antioxidant capacity. The modification of the classical DPPH method, with a methanol-buffer and the measure of EC20 (quantity of sample needed to decrease the initial DPPH concentration by 20%) has shown that sulfur-containing compounds such as cysteine (0.037 ± 0.003), glutathione (0.054 ± 0.003) or methanethiol (0.104 ± 0.003) appeared to bear antioxidant capacity comparable to well known phenolic compounds, such as catechin (0.035 ± 0.003), caffeic acid (0.057 ± 0.003) and ferulic acid (0.108 ± 0.003), respectively. In the case of white wines, the comparison with REDOX-sensory scores showed that results from this modified DPPH assay are strongly correlated with sensory attributes (r = 0.73, p < 0.1). These results provide an unprecedented illustration of the important contribution of these sulfur-containing compounds to the radical quenching ability of white wines.
['Romanet|Remy|R|0000-0003-0779-6139', 'Coelho|Christian|C|', 'Liu|Youzhong|Y|0000-0002-1449-3841', 'Bahut|Florian|F|0000-0002-3288-4846', 'Ballester|Jordi|J|0000-0003-3098-4453', 'Nikolantonaki|Maria|M|0000-0002-5576-9373', 'Gougeon|Régis D|RD|0000-0002-5371-5523']
D000975:Antioxidants D001713:Biphenyl Compounds D002109:Caffeic Acids D002392:Catechin D003373:Coumaric Acids D057166:High-Throughput Screening Assays D006801:Humans D010636:Phenols D010851:Picrates D013457:Sulfur Compounds D014920:Wine
white wine DPPH antioxidant capacity EC20 Chardonnay sensory oxidation level sulfur compounds