UNIVERSITY PARK, Pa. — Consumer preference or aversion to wines made from native grapes — such as Concord, Niagara and Catawba, which are mostly grown in eastern North America — may depend on early exposure to the fruits' sweet, ultra "grapey" taste and aroma, according to researchers who conducted sensory tests with wine drinkers in Pennsylvania and California.
That strong grapey odor, commonly attributed to wines made from these Vitis labruscana grapes, is caused by the compound methyl anthranilate. It is widely accepted that wine experts and discerning consumers find these flavors objectionable in wines made from Vitis vinifera grapes, such as Pinot Noir, Cabernet Sauvignon and Riesling.
Prior work suggests increased exposure to a food product can increase liking, noted John Hayes, associate professor of food science, Penn State, and director of the University's Sensory Evaluation Center. He pointed out that an increasingly competitive wine market is driving researchers to understand the many factors that influence customers' decisions to purchase and consume wine.
"While many of these variables are dependent on marketing, there are intrinsic characteristics of the wine that influence purchase, and these vary among individuals," said Hayes, whose research group in the College of Agricultural Sciences conducted the study. "This research suggests that liking or accepting that 'grapey' aroma presented by native labruscana grapes may be a learned response."
To judge "liking" for the odorant, researchers assessed the preferences of 47 wine drinkers in Pennsylvania, 48 wine drinkers in California and 37 wine experts in California through a series of taste tests. Participants were asked to choose between a relatively neutral Chardonnay and the same Chardonnay spiked with methyl anthranilate in six ascending concentrations. These concentrations were based on levels likely to be found in wines made from both native (labruscana) grapes and vinifera grapes.