Evaluation of Alternative Winemaking Processes for Red Wine Color Enhancement

Abstract

The effects of five novel winemaking technologies on color were evaluated. Cold soak maceration (CSM), dry ice maceration (DIM), prefermentative juice runoff (PJR), delestage (D), and extended maceration (EM) were the process assayed on grapes from Tempranillo variety cultivated in a warm climate zone. Enological and color parameters were determined at stemmed-crushed, pressed, bottled and after 4 months aged in bottle. Significant differences were found in color intensity, percentage of red and blue, and hue at each step of the process and for every technique when compared to the control wine. However, differences tended to decrease with aging. Eleven anthocyanins (glucosides and acylated) were identified, and five quantified by HPLC. Also the anthocyanin distribution in free anthocyanin (% FA), copigmented anthocyanin (% CA) and polimerizated anthocyanin (% PA) were studied. Differences were found for total anhocyanin content, not in their relative abundance. Winemaking processes affected wine's main sensory attributes. DIM achieved a remarkably high valuation for aspect at bottle time, while EM obtained very positive remarks with regards to aroma and persistence at aging DIM and PJR seemed to be the most promising techniques, but after 4-months aging in bottle only EM wine showed a high anthocyanin content.