Tyrosinase Biosensor for the Measurement of Wine Polyphenolics

¹ Department of Viticulture and Enology, University of California, Davis, One Shields Ave., Davis, CA 95616.

email: seebeler{at}ucdavis.edu

Polyphenolics are a broad class of compounds present in many fruits, vegetables, and their products, including grapes and wines. Phenolics are important in winemaking as they contribute many sensorial properties to wines and determine the aging potential of red wine. Current measurements involve monitoring colorimetric chemical reductions and can be time-consuming and generate chemical waste. Biosensors are relatively new analytical devices that offer many advantages over current analytical procedures. In this study, a simple tyrosinase-based biosensor was constructed for the measurement of wine polyphenolics. Excellent correlation was shown between the biosensor and the Folin-Ciocalteu assay for simple phenolics and for model and finished wines. Our results show the tyrosinase-based biosensor to be a rapid, simple, and accurate method for measurement of concentration and reduction potential of polyphenolics in wines.

Note:
Acknowledgments: The authors express their gratitude to Jim Harbertson and Doug Adams, who prepared and generously donated the grape seed tannin used in the study.

Key words: Polyphenols, biosensor, analysis, wine, tyrosinase, op-amp circuitry, Folin-Ciocalteu