Subregional survey of aroma compounds in Marlborough Sauvignon Blanc wines

Background and Aims Marlborough is the largest wine-growing region in New Zealand and Sauvignon Blanc varieties represent over 60% of the vineyard area. The main compounds responsible for the most intense aromas in Sauvignon Blanc wines have been assumed to be methoxypyrazines and varietal thiols; however, the aromatic potential of Sauvignon Blanc wines should not be limited to these compounds. Methods and Results Commercially pressed juices from seven Marlborough subregions were fermented using replicated research-scale winemaking over two harvests. Fifty-five compounds were quantified in the resulting wines, including varietal thiols, methoxypyrazines, reduced sulfur compounds, esters, terpenes, C6 and higher alcohols, fatty acids, C13-norisoprenoids, cinnamates, and aminobenzoates. At least 21 compounds were identified that were present at a concentration above their perception threshold or can enhance the aroma impact of other compounds. Many aroma compounds showed a similar concentration across the subregions and the two seasons, while the concentration of the prominent varietal thiol 3-mercaptohexanol was higher in the second year. Conclusion Considerable diversity exists in the concentration of aroma compounds in Sauvignon Blanc wines across the Marlborough subregions. The green characters ascribed to wines from certain subregions may be linked to a lower concentration of fruity esters as much as to differences in methoxypyrazines, C6 alcohols and certain varietal thiols. Significance of the Study The profiles of aroma compounds in Marlborough Sauvignon Blanc wines have been more clearly defined and the extent of subregional differences has been evaluated for various classes of aroma compounds.