Generally, red wines made from cold-hardy hybrid grapes have much lower tannin content than Vitis vinifera wines and they are often perceived as being of lower quality. This study evaluated the chemistry and sensory perception of whole-cluster (WC) fermented “Frontenac” and “Marquette” red wines from Iowa (F-ISU, M-ISU) and “Marquette” red wines from Minnesota (M-UMN). Three conditions were compared: Control 0% WC (w/w), 25% WC (w/w), and 50% WC (w/w). The 50% WC wines had significantly higher iron-reactive phenolics, tannin, and anthocyanin contents than control wines. The color intensity in 50% WC wines was maintained after 4 months of aging. A tasting evaluation was conducted with the “Marquette” wines from both states and untrained panelists preferred 50% WC “Marquette” wines over control wines. This study showed promising results on the use of 50% (w/w) whole clusters as a pre-fermentative technique to improve “Marquette” and “Frontenac” red wine quality.

In the U.S. Midwest region, interspecific cold hardy grape cultivars have been developed to be resistant to the harsh cold winter, late spring frosts, and hot and humid summer. However, interspecific grape red wines tend to have higher acidity and lower tannins content than Vitis vinifera wines. This leads to unbalanced wines and an increase of the risk of oxidation and therefore impact the overall quality over time. The content and type of phenolic compounds differ in interspecific grapes and wines, depending on the cultivars, the viticultural practices, the environmental conditions and the wine making process. Because the chemical properties of red wines produced from interspecific grapes compared to Vitis vinifera is not well known, it is a challenge to determine the best wine making practices to produce a high quality wine that remains stable over time. This study focuses on evaluating phenolic compounds, oxidation-related compounds, and sulfur dioxide content in Marquette and Frontenac wines aged in bottles for up to 9 years. The goal is to help improve quality of red wines made from interspecific cold-hardy grape cultivars to increase consumer acceptance and develop optimal wine making practices.