Macrowine 2021
IVES 9 IVES Conference Series 9 How do different oak treatment affect the sensory composition of Chenin blanc wines over time?

How do different oak treatment affect the sensory composition of Chenin blanc wines over time?

Abstract

Wooden barrels have been the preferred method for oak maturation for wines, but the use of alternative oak products, such as staves and oak chips have increased in South Africa due to lower production costs. This study investigated the effect of different oak products used during fermentation and ageing on the sensory profile, degree of liking and perceived quality of a South African Chenin blanc wine. The different wine treatments included an unoaked tank control wine, wines matured in 5th fill barrels, wines matured in new barrels from three different cooperages, and wines matured in 5th fill barrels with stave inserts from two different cooperages. All of the treatments, except for the unoaked tank control, were performed in triplicate. Sensory descriptive data were obtained with Pick-K attributes, using a trained and expert panel at three different intervals of wine maturation. These were after 4 months oak maturation, 9 months oak maturation, and 9 months oak maturation with an additional 6 months bottle ageing. At the last maturation interval, an untargeted consumer study was also conducted using CATA questions to obtain descriptive and hedonic data. At this interval the perceived quality of the wines were also investigated using an expert panel consisting mostly of wine producers. The trained panel were trained to recognise aromas from a list of 89 descriptors used by sensory scientists and industry experts to describe Chenin blanc wines. The repeatability of the different treatments were relatively satisfactory from a cooperage point of view. There were clear differences between the sensory profiles of the different wine treatments. However, differences between the oak products from the different cooperages used within treatments were less pronounced. The degree of liking of the consumers and perceived quality of the expert panel of the 5th fill barrels and new barrels were higher than those of the stave treatments. Certain attributes were also observed to be associated with degree of liking and quality, which will be reported on.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Wessel du Toit*, Anri Botha, Jeanne Brand

*Stellenbosch University

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

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