Influence of Different Maceration Approaches and Durations on Phenolic Content in Pinela Wines

Abstract

Introduction: Phenolic compounds are key contributors to wine quality, influencing sensory properties, stability, and aging potential. While well researched in red wines, their importance in white wines has only recently gained attention. Their extraction is strongly influenced by maceration, a technique increasingly used in white winemaking to shape style. This study focuses on Vitis vinifera L. cv. ‘Pinela’, a Slovenian white grape variety from Vipava Valley, renowned for its light, fruit-forward flavors but poorly studied regarding maceration and phenolic composition.

Aim: Evaluating the total phenolic content of Pinela wines produced by different maceration approaches and durations, and deepening the understanding of skin contact in shaping white wine style.

Materials and Methods: Grapes were vinified in four groups: (1) control (no maceration), (2) cold maceration (18 h), (3) maceration during fermentation (24 h, 48 h, 7 days with commercial yeast), and (4) spontaneous fermentation with maceration (7 days, pied de cuve). Total phenolics were measured by the Folin–Ciocalteu spectrophotometric method at 765 nm, expressed as gallic acid equivalents.

Results: Maceration significantly increased total phenolic content compared to the control (224.08 mg/L). Cold maceration resulted in 266.22 mg/L, while fermentative macerations further enhanced extraction, with values of 482.11 mg/L after 24 h and 634.78 mg/L after 48 h. Extended maceration of 7 days gave the highest concentrations: 826.84 mg/L in inoculated and 749.12 mg/L in spontaneous fermentation.

Conclusion: Maceration significantly influenced the total phenolic content of Pinela wines, with both short and extended skin contact resulting in elevated values. Differences observed between inoculated and spontaneous fermentations underscore the importance of fermentation/maceration practices in shaping composition. These findings demonstrate the maceration potential to enhance phenolic content and overall wine character, providing a basis for further research into this variety’s quality attributes.