Glycosidic aroma precursors of Syrah and Chardonnay grapes after an oak extract application to the grapevines

Aroma Glycosides in Grapes and Wine

“…The profiles of aroma glycosides among different grape varieties or cultivars have been explored to a certain extent (Rodriguez and others ; Martínez‐Gil and others ; Panighel and others ). The proportion of glycosidic aroma substances in the total content of aroma substances changes among grape varieties.…”

“…In contrast, Toci and others () did not find any obvious changes in the contents of glycoside compounds when regulating the water stress to study the influence of soil management, such as the cover cropping and soil tillage, on the wine aroma. Interestingly, Martínez‐Gil and others () sprayed oak extracts on grape leaves at different veraison times and found that the oak extracts could be assimilated and stored as glycosidic compounds in grapes.…”

“…The above‐mentioned SPE technology has been applied generally for the enrichment‐purification process of glycosidic aroma precursors (Salinas and others ). The most popularly used C 18 ‐SPE cartridges for the purification of grape aroma glycosides are the LiChrolut EN SPE cartridge (Ibarz and others ; Hernandez and others ; Hernandez and others ; Martínez‐Gil and others ) and Strata‐X 33u Polymeric Reserved Phase SPE cartridge (Martínez‐Gil and others ). The SPE cartridges for column chromatography are fast and usually provide efficient purifications.…”

Volatile Phenols

“…These nonvolatile glycosides could be stored in grapes [26] and hydrolyzed by acid or enzymes during fermentation or storage, subsequently releasing the volatile compounds into wine [27] (Chapter 23.1). These glycosides can also be released in-mouth due to oral microflora (and therefore perceived retronasally) [17,28], and the phenomenon of glycosylation of exogenous volatiles by grape berries and release during fermentation and storage (or enzymatically) has since been extended to studies involving the deliberate application of oak extracts to grapevines in the vineyard [29][30][31]. …”

Induced Changes in Phenolic Composition of Wines After Foliar Application of Eugenol and Guaiacol Solutions to Grapevines

“…Other studies showed changes in the aroma composition of grapes and the wines produced after foliar application of an aqueous oak extract (Martínez-Gil et al, 2013;Martínez-Gil, Garde-Cerdán, Martínez, Alonso, & Salinas, 2011;Martínez-Gil, Garde-Cerdán, Zalacain, Pardo-García, & Salinas, 2012). Oak extract is composed by a diversity of compounds, such as polyphenols and volatiles, being eugenol and guaiacol among them.…”