Hybrid wines scored alongside pinot noir on appearance in a blind Cornell panel

About 8% of the variation explained works out to a correlation of roughly 0.28 between how a panelist rated a wine's appearance and how much they liked drinking it ^[8][2]. Around 92% of the variation in liking sat somewhere else ^[1]. Colour still did something: the paler wines, and those showing yellow and brown tones, scored lower on visual appeal and produced weaker expectations before anyone tasted ^[6]. "The fact is, taste and aroma are so much more important than color in overall quality perception," said Catherine Dadmun, a food science doctoral student at Cornell and a co-author ^[13][20].

The design was built to catch the gap between the first look and the verdict after tasting. Panelists saw each wine, rated its appearance, said how much they expected to enjoy it from colour alone, then tasted and rated again, without knowing which wine was which ^[5]. That removes the label, the price and the grape name.

Anna Katharine Mansfield, associate professor of enology at Cornell AgriTech, said the assumption had never been tested ^[19]. "Prior to coming to Cornell I worked with breeders at the University of Minnesota and often there was this idea that consumers would reject a wine if its color didn't look very Vitis vinifera-like. But no one had ever studied that question," she said ^[9].

The eight bottles were commercial wines. Five came from hybrid cultivars grown in New York, Wisconsin, Tennessee and Iowa, and the other three were pinot noirs from Burgundy, Oregon and the Finger Lakes ^[4]. A commercial bottle carries its winemaker's decisions about extraction, oak and ageing along with its grape, so the flight compares wines as they were made. Several of the hybrid wines were among the most visually appealing in the study ^[18]. One of the three lowest scorers on appearance was itself a pinot noir, from the Finger Lakes, sitting with a Norton from Tennessee and a corot noir from near Albany ^[7][3].

Chemistry was part of the reason for running the experiment. "Especially in Europe, there are historic restrictions on the chemical color compounds that appear uniquely in hybrid grapes," Dadmun said. "This has led to the assumption that these compounds must result in low-quality color" ^[11][12].

The 82 panelists were regular red wine drinkers recruited through the Cornell Sensory Evaluation Center ^[3]. The skepticism the study set out to examine was attributed to winemakers and sommeliers, and they were not the people rating the wines ^[2]. The published account of the results gives the appearance comparison by variety and not the taste-liking ranking, and Dadmun's summary is specific about which measures overlapped: "When we evaluated hue-liking and overall appearance-liking, the pinot noirs and hybrid grapes were largely in the same pool," she said ^[14].

For a grower, this narrows one of the doubts that has slowed planting, and only that one ^[16]. Marquette, Maréchal Foch and St. Croix can be grown with far fewer pesticide applications and survive winters that would devastate conventional vineyards ^[15]. On the question of colour, the Cornell data showed no meaningful correlation between colour intensity and how much drinkers actually liked the wine ^[17].