Accelerated oxygenation for the production of fortified (mystelle-type) sweet wines: effects on the chemical and flavor profile.

Background: Fortified wine is an important category in the wine world with very famous wines such as Porto or Jerez-wine type. The quality of fortified wines increased significantly with barrel aging not only because of a long oxidation process, but also because, in Porto wines such as Ruby or Vintage styles, the long period in bottle permits their fining. Reducing the time of oxidation can favor the development of this technique even for less known sweet wines, making them good quality and less expensive. In the present study, we have used Gamay red variety subjected to postharvest controlled dehydration at 20-22 °C and 70-75% relative humidity with an airflow of 1 m s^-1. Then the grapes were pressed, and alcohol was added to the must up to an alcohol content of 15.85% (mystelle-type wine). The mass was split into six glass jars, three were oxygenated (OX) and three not (Control), and the oxygenation lasted 62 days.

Results: Wine that was oxygenated had a slightly higher volatile acidity, lower alcohol content (13.00%), and lower anthocyanins and polyphenols content. In term of volatile organic compounds (VOCs), the Control wine had a higher content of alcohols, whereas the OX sample had a higher content of lactones, furans and esters. Sensory evaluation confirmed the VOCs analysis; the two wines had a statistically different profile depending on the oxidation treatment. In general, OX wine was more appreciated in terms of visual attractiveness, taste and olfactory pleasantness.

Conclusion: In conclusion, the technique described in the present study could be a valid alternative to traditional aging of fortified sweet wines, reducing time and costs. © 2024 Society of Chemical Industry.