Investigation of grape skin thickness and grape skin lipid content for differences in smoke taint composition

Abstract

A plant’s cuticle layer is an external waxy barrier to the lipid membrane and the plants first line of defense. The cuticle and membrane layers’ morphology and composition change in response to the fruit’s developmental stage and physiology. It is important to understand how the developmental changes of these barriers affect the fruit’s defense to environmental exposures. This work investigates the formation of smoke related compounds and the relationship with cuticle and lipid membrane layers of grape skins. In particular it is of interest to determine if these two factors are playing a role in the different levels of smoke taint that arise within different varietals during the same smoke event. Twelve Vitis vinifera wine grape varietals (Cabernet Sauvignon, Cabernet franc, Merlot, Petite Verdot, Pinot noir, Syrah, Malbec, Tempranillo, Chardonnay, Viognier, Pinot gris, and Sauvignon blanc) were investigated. Grapes were harvested at 2 time points and smoked in custom smoking chambers, as no natural event occurred that year. Skin thickness was measured using Scanning Electron Microscopy (SEM) and compared with smoked volatile polyphenol and smoked thiol concentrations to determine if there is a varietal difference in smoke taint. Skin lipid extraction was measured using UHPLC-MS/MS to determine if the lipid composition of the skin effects smoke taint formation.

References

Arand, K., Bieler, E., Durrenberger, M., and Kassemeyer, H.H. 2021. Developmental Pattern Of Grapevine (Vitis vinifera L) Berry Cuticular Wax: Differentiation Between Epicuticular Crystals And Underlying Wax. PLOS ONE. 16(2): e0246693. doi: 10.1371/journal.pone.0246693.

Boban, A., Masuero, D., Vrhovsek, U., and Budic-Leto, I. 2023 Comprehensive Lipid Profile of ‘Marastina’ Grape Skins from Dalmatia. Applied Sciences. Appl. Sci. 13, 6446. https://doi.org/10.3390/app13116446

Chang, B.M.; and Keller, M. 2021. Cuticle and Skin Cell Walls Have Common and Unique Roles in Grape Berry Splitting. 2021. Horticulture Research. 8(168).

Zhang, M., Zhang, P., Lu, S., Ou-yang, O., Zhu-ge, Y., Tian, R., Jia, H., and Fang, J. 2021. Comparative Analysis of Cuticular Wax in Various Grape Cultivars During Berry Development and After Storage. Front. Nutr. – Food Chem. 8:817796. doi: 10.3389/fnut.2021.817796.