Abstract

AbstractThere is a very strong interaction between sulphur dioxide (SO2) and 0‐dihydroxy phenols in response to the Folin–Ciocalteu colorimetric assay, currently the established procedure for analysis of total phenols in wines and plant extracts. Because of this previously unsuspected interference, the method is shown to be generally quite invalid in application to white wines; measures of total phenols may be magnified several‐fold by the SO2 artefact. By use of model solutions, it has been shown that the extent of interference depends primarily on the molar ratio of SO2:0‐dihydroxy phenols. The mechanism of the artefact can be interpreted with reference to the chemistry of the photographic process, in which the oxidation‐reduction reactions involved in image development are similarly mediated by the presence of bisulphite in alkaline solution.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.