Simplification of the DPPH assay for estimating the antioxidant activity of wine and wine by-products

• Published in: Food chemistry Vol. 165; pp. 198 - 204
• Main Authors: CARMONA-JIMENEZ, Yolanda, VALME GARCIA-MORENO, M, IGARTUBURU, Jose M, BARROSO, Carmelo Garcia
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier 15-12-2014
• Subjects: Alcoholism and acute alcohol poisoning; Antioxidants - analysis; Biological and medical sciences; Biphenyl Compounds - analysis; Biphenyl Compounds - chemistry; Food toxicology; Kinetics; Medical sciences; Oxidation-Reduction; Picrates - analysis; Picrates - chemistry; Toxicology; Vitaceae; Wine - analysis; Assay; Wine; Alcoholic beverage; DPPH; Antioxidant activity; Routine analysis; Antioxidant; By product; EC
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2014.05.106

The DPPH assay is one of the most commonly employed methods for measuring antioxidant activity. Even though this method is considered very simple and efficient, it does present various limitations which make it complicated to perform. The range of linearity between the DPPH inhibition percentage and sample concentration has been studied with a view to simplifying the method for characterising samples of wine origin. It has been concluded that all the samples are linear in a range of inhibition below 40%, which allows the analysis to be simplified. A new parameter more appropriate for the simplification, the EC20, has been proposed to express the assay results. Additionally, the reaction time was analysed with the object of avoiding the need for kinetic studies in the method. The simplifications considered offer a more functional method, without significant errors, which could be used for routine analysis.