Characterization of Canadian Ice Wines by Sensory and Compositional Analyses

Abstract

The sensory and compositional profiles of 25 Canadian and German ice wines were determined using descriptive, physicochemical, and volatile analyses. Color, 9 aroma attributes, and 12 flavor/taste attributes were evaluated by a trained panel of 25 judges using a balanced incomplete block design. Ice wines were analyzed for titratable acidity, pH, color (A_{420 nm} and A_{520 nm}), viscosity, total sugar, and ethanol. Thirty-four volatile compounds (alcohols, esters, acids, terpenes, furans, sulfurs, miscellaneous) were quantified in the ice wines and six table wines using gas chromatography-mass spectrometry. Eight volatile compounds differed significantly between British Columbia and Ontario ice wines. Gas chromatography olfactometry (odor port detection) was used to describe the perceived aroma of 34 odor-active volatile compounds. Cobweb diagrams and principal component analysis (PCA) indicated that Ontario ice wines had the highest fruity and floral aromas and a golden copper color. German ice wines had higher acidity with a nutty/oily character, while sweetness, body/viscosity, and intensity of aftertaste were more pronounced in British Columbia ice wines. British Columbia ice wines had the highest viscosity, titratable acidity, and total sugar. Ontario ice wines had the highest color absorbance values, while the German ice wines had the lowest viscosity, total sugar, and ethanol. PCA plots of the volatile compounds showed clear separations among the Canadian ice wines, German ice wines, and table wines. A PCA plot of the combined sensory aromas and 14 odor-active volatile compounds also showed a separation of Canadian and German wines and identified relationships between sensory and volatile analyses.