The terroir plays a crucial role in shaping the stylistic features of grape. Chardonnay is a popular grape variety among consumers, but it is not clear how the terroir of sub-regions affects its volatiles typicality. Hence, Chardonnay grape berries from three representative vineyards (Zhi Hui Yuan Shi/ZH, Yu Quan/YQ, Xi Ge/XG) in sub-regions on the eastern foothills of Helan Mountain were collected at harvest, and the corresponding wine was brewed over two consecutive years. The HS-SPME method, multivariate analysis, organoleptic evaluations, and correlation matrix were employed to identify biomarkers and terroir factors. The ZH grapes exhibit smaller berries with higher soluble solids and acidity content. They have the highest concentrations of aromatic compounds, particularly showing significantly concentrations of alcohols, esters, terpenes, and norisoprenoids compounds than other vineyards. Meanwhile, the wine produced from ZH grapes received the top overall rating, while XG grapes had contrasting outcomes. YQ grapes were characterized by the high acidity and the greatest concentration of C6/C9 compounds. Additionally, the characteristic aroma biomarkers were identified to distinguish grape berries from different sub-regions. The results of the association between terroir factors and aroma biomarkers indicated that the higher average temperatures in May and June, and nutrient-rich soil contributed to the accumulation of norisoprenoids, acids, and esters, whereas lower average monthly temperatures, fewer hours of sunshine and lower soil nutrient levels increased the content of C6/C9 compounds. These results provide key insights into improving the diversity of wine styles by terroir of sub-regions in the eastern foothills of Helan Mountains.
Hu et al. (Fri,) studied this question.