Investigating the Use of Barrel Microoxygenation for Accelerated Red Wine Aging
Cristina Medina-Plaza, Lik Xian Lim, and Anita
Oberhoslter*
*UC Davis, 595 Hilgard Ln, Davis, CA, 95618
(aoberholster@ucdavis.edu)
Barrel-maturated wines are enriched in aromatic compounds, their color is more stable and mouthfeel complexity is improved. The extraction of oak phenolics is governed by diffusion kinetics: the rate of extraction is initially high, decreasing when the concentration in the wine approaches that on the surface of the barrel. Additionally, oxygen plays an important role in wine aging, stabilizing color, and more. Microoxygenation in combination with barrel aging could accelerate wine aging, reducing the time that wine spends in-barrel while still obtaining the benefit of oak aromatics. In this project, a red wine blend was aged in barrel and stainless steel vessels using different rates of O2 dosing (0, 1, and 2 mg/L/month). The 2 mg/L/month treatment was stopped after three months, while the 1 mg/L/month treatment was applied for six months. The barrel treatments without MOX continued for 12 months. Dissolved oxygen (DO), volatile acidity, and free and total SO2 levels were monitored weekly. Acetaldehyde-adducts and phenolics were determined by RP-HPLC. Results showed that wines reached similar levels of acetaldehyde at the end of each treatment, independent of MOX level. Total tannins increased over time, particularly in the wines aged in barrels, and total anthocyanins decreased over time, paired with an increase in polymeric pigments in all wines. PCA of all the chemical data indicated that the six months O2 treatment at 1 mg/L/month showed comparable aging to the barrel treatment without MOX after 12 months; however, during consumer studies, judges preferred the barrel aged wines with no MOX during 12 months over the rest of the treatments. No significant differences were found hedonically among the rest of the wines, suggesting that MOX could be used to shorten aging time in barrel, but must be studied further, as its impact is very specific to the wine.
Funding Support: Lyon-Cisneros Family Research Fund
