Mechanical summer pruning of 'Syrah' grapes in arid and semi-arid regions: the impact of canopy thickness on grapes and wine phenolic compounds

Mechanical summer pruning of 'Syrah' grapes in arid and semi-arid regions: the impact of canopy thickness on grapes and wine phenolic compounds

Bian, Lu ; Yu, Xince ; Zhang, Zhixin ; Tong, Yi ; Zhang, Liang ; Xu, Qian ; Fu, Jiahao ; Wang, Qiqi ; Zhao, Wen ; Wang, Jie ; Chen, Hongmei ; Meng, Jiangfei ; Zhang, Fuchun ; Xu, Yan ; Xu, Tengfei

FOOD CHEMISTRY

DOI：10.1016/j.foodchem.2026.148640

Abstract

Canopy management is important in viticulture, as removing lateral shoots mitigates nutrient competition and consequently enhances the quality of grapes and wine. This study focused on 'Syrah', the main grape cultivar in the northern foothills of the Tianshan Mountains in Xinjiang, which is a typical arid and semi-arid region. Four canopy thicknesses (40, 60, 80, and 100 cm) were established to investigate their effects under mechanized management. Results revealed that thicker canopies altered microclimate and grape quality. In particular, 60 and 80 cm-thick canopies significantly increased the levels of total phenols, total flavonoids, flavan-3-ols, and monomeric phenolic compounds in both grapes and wine. Canopies with a thickness of 60 cm showed the highest non-anthocyanin phenol levels and sensory scores and excellent stability. Therefore, 60 cm-thick canopies are recommended for the mechanized pruning of 'Syrah' grapes to produce high-quality wine in the study region.