Rootstocks of prestigious Bordeaux vineyards: implications on quality and yield

Nowadays there are many challenges facing both winegrowers and workers, in other agricultural practices, related to the growing demand for food products, the safety and quality of these products, and the preservation of the environment…

The concept of viticultural terroir includes soil, sub-soil, and climatic factors but also many management viticultural and oenological practices which are chosen according to know-how of the winegrowers.

Saccharomyces cerevisiae (SC) is the main driver of alcoholic fermentation however, in wine, non-Saccharomyces species can have a powerful effect on aroma and flavor formation. This study aimed to compare untargeted volatile compound profiles from SPME-GC×GC-TOF-MS of Sauvignon blanc and Shiraz wine inoculated with six different non-Saccharomyces yeasts followed by SC. Torulaspora delbrueckii (TD), Lachancea thermotolerans (LT), Pichia kluyveri (PK) and Metschnikowia pulcherrima (MP) were commercial starter strains, while Candida zemplinina (CZ) and Kazachstania aerobia (KA), were isolated from wine grape environments. Each fermentation produced a distinct chemical profile that was unique for both grape musts. The SC-monoculture and CZ-SC sequential fermentations were the most distinctly different in the Sauvignon blanc while the LT-SC sequential fermentations were the most different from the control in the Shiraz fermentations.

The brown marmorated stink bug (BMSB, Halyomorpha halys Stal) is an invasive pentatomid native to eastern Asia that is spreading rapidly worldwide, notably through human-mediated activities. Globally, it was reported in the USA, Canada, Italy, Hungary, and other European countries. BMSB has a broad host range that includes over 170 plants, many of agricultural importance, including various fruit, vegetables, row crops, and ornamentals. When present in the vineyard, the pest can affect yield and quality by directly feeding on berries resulting in fruit collapse and necrosis. Additional damage occurs when BMSB are carried into the winery within the grape clusters. The presence of BMSB during wine processing can affect juice and wine quality through the release of volatile compounds produced as a stress response. The major secretes compounds are tridecane and trans-2-decenal. Tridecane is an odorless compound and its effect on wine quality is currently unknown. Trans-2-decenal is an unsaturated aldehyde considered to be the main component of BMSB taint with strong green, coriander, and musty-like aromas. Its threshold value in wine was estimated at about 5 µg/L.

Aging wine on lees benefits different wine sensory and technological properties including an enhanced resistance to oxidation. Several molecules released by yeast, such as membrane sterols and glutathione, have been previously proposed as key factors for this activity [1].