Project number
WW JT 19-01
Project leader
Dr Jose-Luis Aleixandre-Tudo
Institution
South African Grape and Wine Research Institute, Department of Viticulture and Oenology, Stellenbosch University
Project is co-funded by The Department of Science and Innovation
Date completed
2022
Objectives and Rationale
This project aims to provide a technological solution to quantify phenolic content during the most critical steps of winemaking. The objective is to provide a portable device to measure phenolics during the maceration of red wines and the pressing of grapes for sparkling and white wine production.
Methods
The portable device makes use of the fluorescence and ultraviolet signal of wines. The spectral data is transformed in phenolic levels with advanced regression techniques and the optimisation of prediction calibrations. This approach makes the quantification of multiple phenolic parameters possible with the use of a single spectral measurement.
Key Results
An optimised portable fluorescence spectrometer coupled with a measuring chamber was developed. The quantification and monitoring of the phenolic extraction during red wine maceration and white and sparkling wine pressing would be possible towards optimising the wine’s sensory profiles and quality.
Key Conclusion of Discussion
This represents a significant improvement in how phenolic data will be available to winemakers and will assist in optimising the phenolic resources and final wine quality. This project provides enhanced process control, optimisation and understanding of the winemaking process with potential implications for wine quality standards.
Take Home Message for Industry
Oenological products or winemaking practices can be optimised by regular measurement of phenolic content during the winemaking process. This portable device can provide such information.