Renee T. Threlfall

Compositional and Sensory Impacts from Blending Red Wine Varietals

Wine consumers are interested in components of red wines that contribute to health effects, flavor, and color. Three Vitis vinifera wines (Cabernet Sauvignon, Merlot, and Zinfandel) were blended using formulas created by an augmented simplex centroid mixture design, resulting in 10 wines (three single-component wines, three binary blends, and four tertiary blends). Compositional and color components of the wines were analyzed during 12 months of storage at 15°C with descriptive analysis and consumer evaluations at 30 days. Blending impacted compositional components and sensory profiles of the wines. During 12 months of storage, the blended wines exhibited similar compositional and color changes as their single counterparts; total anthocyanin content decreased and red color density and percent polymeric color increased. The primary anthocyanins detected in the wines by HPLC analysis were malvidin-3-O-monoglucoside, typical of V. vinifera. The anthocyanins decreased during storage with the formation of pyranoanthocyanins from condensation reactions. When descriptive and compositional analysis were compared, red color intensity and depth of color were correlated (r > 0.85) with clarity, flavor intensity, red color density, L*, chroma, total anthocyanin content, and polymeric color content. When consumer evaluations and compositional analysis were compared, consumer liking of appearance of the wines was positively correlated to red color density (r = 0.83), total anthocyanins (r = 0.85) and percent polymeric color (r = 0.93) and negatively correlated to L*(r = 0.99), chroma (r = 0.91), and hue (r = 0.99). Blending light-bodied wine with full-bodied wine positively affected consumer acceptance. Sensory and compositional data can be used to determine the overall impact of critical parameters for blending V. vinifera wines.

Sensory, Compositional, and Color Properties of Nutraceutical-Rich Juice Blends

Phytochemical-rich fruits may have health-related properties, which make juices of these fruits prime candidates for the nutraceutical market. Understanding consumer acceptance and compositional, color, and descriptive sensory changes during storage is crucial to the success of nutraceutical-rich juices. Juices (blackberry, blueberry, and Concord grape) were blended according to the ABCD mixture design (three primary juices, three binary blends, and four tertiary blends). Prior to storage, a trained descriptive panel (n = 8) determined that Concord-containing blends were generally sweeter, less bitter, less astringent, and less sour than blackberry- or blueberry-containing blends. When relating compositional, color, and descriptive sensory characteristics, sweetness was inversely correlated to total phenolics (r = −0.88), total anthocyanins (r = −0.75), color density (r = −0.84), and astringency (r = −0.92) and positively correlated with soluble solids (r = 0.92) and polymeric color (r = 0.78). Consumers (n = 108) evaluated overall liking on a 9-point verbal hedonic scale. Average liking scores were high for 100% Concord juice (7.79), moderate for 100% blueberry juice (5.47), and low for 100% blackberry juice (2.95). Consumer acceptance was driven by soluble solids, total anthocyanins, purple color, red color, astringency, sweetness, and grape flavor. Compositional, color, and descriptive sensory changes were tracked during 200 days storage at 2°C and 21°C. Prior to storage, 100% blueberry juice had the highest total anthocyanins (67 mg/100 mL), 100% blackberry juice had the highest total phenolics (249 mg/100 mL), and 100% Concord juice had the highest polymeric color (23%). During storage, polymeric color increased as total anthocyanins decreased at 2°C and 21°C. Blending juices balanced nutraceutical enhancement and maintenance of consumer acceptance.