Extended Maceration and Cap Management Impacts on the Phenolic, Volatile, and Sensory Profiles of Merlot Wine

The present study aimed to evaluate the sensory and chemical effects of nine cap management and maceration techniques. Extended maceration (EM) was applied to Vitis vinifera L. cv. Merlot for 0, 1, 2, 4, 6, and 8 wks. In addition, a punch-down treatment and two submerged-cap treatments were also evaluated, giving a total of nine treatments. Descriptive analysis, polyphenolic measures, basic wine parameters, and volatile compound analysis were used to describe these nine treatments. EM defined the astringent texture of the resulting wines, while cap management modified the bitter taste and pepper spice aroma. In total, 27 of 29 measured volatile compounds exhibited a significant treatment effect, thus demonstrating the importance of these enological practices on the final volatile profile. Correlation with EM length was shown for 15 of the significant volatile compounds. In particular, the ester profile of the wines displayed decreased variability after 2 wks of maceration. The results of this study suggest that EM may not be as impactful on astringency as previously thought, due to the fact that EM only significantly affected this attribute after 6 wks. Additionally, the results of the cap management treatments indicated that bitterness can be modified by punch-down versus pump-over techniques.