Chemical and Sensory Effects of Cold Soak, Whole Cluster Fermentation, and Stem Additions in Pinot noir Wines

Abstract

Pinot noir wines were produced over two consecutive vintages using four and six different winemaking techniques in 2014 and 2015, respectively. In addition to control wines, the separate and combined effect of cold soak (CS) and additions of 20% whole clusters (WC) and 3% stems were investigated for their effect on phenolics, color, volatile composition, and sensory composition of the resulting wines. The basic chemistry of the wines was minimally affected by CS, WC, or stem treatments. In the cooler 2014 vintage, CS increased tannin extraction by 37% relative to control treatment but did not affect tannin extraction in the warmer 2015 vintage. Addition of stems increased tannin extraction by 60%. CS decreased anthocyanin extraction and color intensity in both vintages. Absolute concentration and odor activity value of β-damascenone were higher in control and control + WC wines than in CS wines, suggesting that the control and control + WC wines were fruitier than CS wines. Sensory descriptive analysis of the wines indicated that in the 2014 vintage, control wines were the least saturated in color and CS + WC wines were the most saturated. However, the opposite was found in 2015, whereby CS decreased color saturation. Control wines were fruitier whereas WC wines were less fruity but higher in floral and bitter almond aromas. This aroma shift was likely due to the influence of the added stems. WC and stem additions had a moderate effect on the diversity of aromas and a larger, enhancing effect on bitter taste and astringency within the sensory profile of these Pinot noir wines.