Effects of Different Parcels on the Aroma Substances of Wine Grapes from Eastern Foothill of Helan Mountain

In order to clarify the significance of the division of small wine production regions in the eastern foothill of Helan Mountain in Ningxia, the free and bound aroma substances in the mature fruits of two wine grape varieties from four vineyards in the eastern foothill of Helan Mountain were determined by gas chromatography-mass spectrometry (GC-MS), and the influence of different parcels on the aroma composition of wine grapes was analyzed. The results showed that the soils of these four parcels were all sandy loam. The soil of the Gaojiazha parcel contained more clay, the Zhihui parcel was close to sandy soil, and the soil texture of the Huaxi and Jinshan parcels was between the Zhihui and Gaojiazha parcels. The 100-berry mass, 100-berry volume and titratable acid content of Chardonnay grapes from the Zhihui parcel were significantly higher than those of Chardonnay grapes from the Gaojiazha parcel. No significant variation in the 100-berry mass or 100-berry volume of ‘Cabernet Sauvignon’ berries was found among the different parcels. However, ‘Cabernet Sauvignon’ berries from the Jinshan parcel had higher soluble solids content but lower titratable acid content. The types and contents of aroma substances in ‘Cabernet Sauvignon’ and ‘Chardonnay’ berries were significantly different among these four parcels, mainly in terms of the amounts of C₆/C₉, norisoprenoids, esters and terpenes. ‘Chardonnay’ grapes from the Zhihui parcel contained more free (E)-2-hexenal, β-damasone and bound octanoic acid ethyl ester, and had stronger floral, fruity and green aromas based on odor activity values (OAVs). ‘Cabernet Sauvignon’ grapes from the Jinshan parcel contained more free (E)-2-hexenal and (Z)-3-hexen-1-ol, and had a stronger green aroma based on OAVs.