GORENA, T.; MARDONES, C.; VERGARA, C.; SAEZ, V.; VON BAER, D.
ACS Symposium Series (Advances in Wine Research) 1203 (2015) 347-393.
The health-promoting properties of stilbenoids have been widely documented. In plants, stilbenoids form part of a complex defense mechanism, playing an important role in the response to biotic and abiotic stress in grape vines. The health benefits of (E)-resveratrol have been used to promote moderate wine consumption. However, wine contains only 0.4–8.1 mg·L-1 of (E)-resveratrol. Approaches to increase these levels in grape vines involved subjecting the vines to different growing conditions, and irradiating grapes with UV-C light. These methods increased the stilbenoid levels in grapes; however, the levels were still much lower compared to grape canes obtained after pruning the vineyard. In grape canes, the (E)-resveratrol concentration can reach up to 5959 mg·kg-1 DW. In Vitis vinifera canes stored for some months after pruning, the concentration of (E)-resveratrol increased five-fold (based on dry matter). The mechanism of this increase is still unknown, but indeed it has a significant impact on the potential of grape canes as a source of stilbenoids. Cane-management after pruning has a greater influence on this potential than the grape variety or other factors.