Accentuated cut edges (ACE): effects of skin fragmentation on the composition and sensory attributes of Pinot noir wines

The phenolic composition, aroma, and sensory profiles were evaluated for Pinot noir wines made using four different maceration techniques that modified the floating pomace cap during fermentation: 1) daily plunging; 2) reduced skin particle size (accentuated cut edges, ACE); 3) submerged cap; and 4) ACE plus submerged cap. Throughout vinification, wines were analyzed using rapid analytical techniques to assess the following phenolic attributes: anthocyanin, tannin, nonbleachable pigments, color density, and hue. At six months bottle age (230 days postinoculation), sensory and aroma analyses were conducted on the finished wines. ACE macerated wines were found to have the highest proportion of red color, tannin, nonbleachable pigments, fruit and floral aromas, bitterness, and astringency. Submerging the pomace cap resulted in a lower concentration of phenolic components when compared to ACE wines, but resulted in a significantly higher phenolic content and dark cherry aromas and flavor when compared to the control wine. These findings suggest that the employment of either maceration technique has the potential to make a considerable difference to the wine style produced from a given parcel of fruit and may provide an opportunity to press wines earlier in the fermentation. Linear regression analyses were conducted to compare descriptive wine parameters with instrumental phenolic measurements and demonstrated several strong correlations: red color appearance was correlated with both color density (r² = 0.95) and nonbleachable pigment (r² = 0.95); dark fruit flavor was correlated with both color density (r² = 0.85) and nonbleachable pigment (r² = 0.85); and astringency was correlated with both tannin (r² = 0.97) and nonbleachable pigment (r² = 0.87), demonstrating that techniques of rapid chemical analysis were able to provide valuable insights into the sensory properties of the wine and may become useful tools for monitoring the development of the wine during vinification. While submerged cap vinification also increased the tannin and nonbleachable pigment profiles of the wine, ACE maceration was found to be significantly more effective and is likely to be more readily adapted for application in commercial wineries.