Modeling viticultural landscapes: a GIS analysis of the viticultural potential in the Rogue Valley of Oregon

Background: Aroma compounds are important secondary metabolite in grapes and play important roles in the flavor and quality of grape berries and their wines. Vitis amurensis grape belongs to the East Asian Vitis spp., with excellent cold and disease resistance, and exhibits strong brewing potential. However, it has not been effectively utilized and there is no systematic research on the aroma compounds of V. amurensis grapes. Methods: To provide sufficient experimental evidence for the characteristic aroma of V. amurensis grape, HS-SPME-GC/MS was used to identify the aroma compounds of five V. amurensis (‘Beiguohong’, ‘Beiguolan’, ‘Shuangfeng’, ‘Shuanghong’, ‘Shuangyou’) and three interspecific hybrids (‘Beibinghong’, ‘Xuelanhong’, ‘Zuoyouhong’) grapes in Zuojia and Ji’an. The grape berries were collected at harvest in 2020, 2021 and 2022.

During red wine aging, numerous chemical reactions occur, contributing to the modification and enhancement of the wine sensory parameters over time [1].

In a highly competitive worldwide market, a current challenge for the beverage sector is to diversify the range of products and to offer wines and spirits with typicity and character.

During alcoholic fermentation, wine yeasts generate a large variety of volatile metabolites, including acetate esters, ethyl fatty acid esters, higher alcohols, volatile fatty acids and volatile sulfur compounds that contribute to the aroma profile of wine. These molecules, refered as fermentative aromas, are the most abundant volatile compounds synthetized by yeasts and the metabolic pathways involved in their formation have been well characterized. Furthermore, other molecules with a major organoleptic impact may be produced during wine fermentation including terpene derivatives. However, little information is available on the contribution of yeasts to the formation of these molecules, in particular on their ability to synthethise de novo the terpens derivatives or to produce hydrolytic enzymes involved in the release of varietal precursors.

In most viticultural regions, grapevines are cultivated grafted, employing either hybrid or pure species of various American Vitis spp., such as V. berlandieri, V. rupestris, and V. riparia, as grapevine rootstocks. These rootstocks play a crucial role in providing resistance to the Phylloxera insect pest. Beyond Phylloxera resistance, it is desirable for grapevine rootstocks to exhibit resistance to other soil-borne pathogens and adaptability to abiotic stress conditions. The introduction of new rootstocks holds promise for adapting agriculture to climate change without altering the characteristics of the final harvested product.

Cognac is a famous spirit produced in southwest France in the region of the eponymous town from wines mainly from Vitis vinifera cv. Ugni blanc. This variety gives very acidic and poorly aromatic base wines for distillation which are produced according to a very specific procedure. Grapes are picked at low sugar concentrations ranging 13-21 °Brix and musts with high turbidity (>500 NTU) are fermented without sulphite addition [1]. Fermentative aromas, as esters and higher alcohols, are currently the main quality markers considered in Cognac spirits.