Macrowine 2021
IVES 9 IVES Conference Series 9 Evaluating South African Chenin blanc wine styles using an LC-MS screening method

Evaluating South African Chenin blanc wine styles using an LC-MS screening method

Abstract

Sorting Chenin blanc is one of the most important white wine cultivars in South Africa. It has received a lot of attention and accolades in the past years and more research than ever is dedicated to this versatile cultivar. According to the Chenin blanc association of South Africa, there are three recognized dry wine styles, Fresh and Fruity (FF), Rich and Ripe Unwooded (RRU), and Rich and Ripe Wooded (RRW). They are traditionally established with the aid of expert sensory evaluation, but the cost and the (subjective) human factor are aspects to be taken into account. A more objective and possibly robust way of assessing and attributing these styles can be the use of chemical analysis. A sample set of 18 wines were subjected to sensory evaluation by 30 experts using first free and then directed sorting tasks, taking into account both aroma and taste. The data has been analysed using DISTATIS to assess individual differences between samples as well as to build a multivariate map of the data. The same samples were also analysed by LC-MS using a screening method developed for this purpose. The data generated was analysed using MarkerLynx XS (Waters Corporation), an application manager that performs 3D peak integration, data set alignment and incorporates multivariate statistical tools. The software is directly integrated with Umetrics SIMCA-P and the PCA algorithm is directly applied to the processed data sets. The sensory and chemistry data sets were treated separately and groupings of samples around the predefined styles were found for both sets. Results indicate that even though the traditional evaluation of Chenin blanc styles has its merits, a more objective way of attributing the style is also possible with the help of chemical analysis coupled with integrated statistical tools.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Astrid Buica*, Christine Wilson, Jeanne Brand, Marietjie Stander

*Stellenbosch University

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

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