WINETECH Technical Yearbook 2019

ASTRID BUICA, MPHO MAFATA, VALERIA PANZERI & JEANNE BRAND: Department of Viticulture and Oenology, Stellenbosch University, Stellenbosch KEYWORDS: Storage conditions, Chenin blanc wine, Sauvignon blanc wine, thiols, antioxidants. NOVEMBER 2019 STABILITY OF YOUNG CHENIN BLANC AND SAUVIGNON BLANC WINE DURING STORAGE (PART 1): CHEMICAL EVALUATION

The aim of this study was to evaluate the stability of commercial white wines aroma using both analytical chemistry and sensory evaluation approaches, with a focus on the stability of thiols. The results of the study will be presented in a two-part article, each covering one aspect of the work. Part 1 is focused on the evolution of some relevant classes of aroma compounds, namely thiols and major volatiles (esters, organic acids and higher alcohols) and of antioxidant-related parameters (glutathione, phenolics and colour). WINE AROMA STABILITY The availability of information on the stability of wine aroma and aroma compounds is

dependent on the cultivar and compounds of interest. Work done on New Zealand Sauvignon blanc can offer a basis for what to expect during wine storage in different conditions. For Chenin blanc, some hypotheses can be proposed based on the research done on Sauvignon blanc. While there is other work published internationally that is of general relevance, the research usually deals with the overall aroma stability, especially as affected by oxygen exposure during storage. There is still a need to elucidate the fate of thiols in Chenin blanc and the effect storage conditions have on the wines both from a chemical and sensory point of view. There is always an interest in the elucidation of various aspects linked to wine stability using