Oxygen is present in about 20% of the air we breathe and is essential for all organisms that inhabit this planet. Without this element, life on Earth would not be possible and, for this reason, everyone benefits.
But in the winemaking world, this rule doesn’t always apply.
Oxygen management must be carefully monitored to prevent excessive oxidation reactions that can negatively impact the final quality of wine. It is important to apply specific tools and techniques that allow for proper and natural ageing, while maintaining and preserving quality.
Oxygen is the key player in oxidative reactions
Oxidation reactions can deteriorate the sensory profile leading to aromatic losses, taste imbalances, and effects the final color:
White wines tend to take on more golden hues until they turn brown, |
while red wines will turn to a brick/brown color. |
Enzymatic Oxidation: Occurs mainly in must by polyphenoloxidase. The most important are tyrosinase and laccase (in the case of grapes affected by Botrytis cinerea). These enzymes catalyze oxidation of ortho-diphenols by transforming them into ortho-quinones, from which color changes (browning) are generated.
Chemical oxidation: The presence of O2, with metals such as iron and copper, can lead to the appearance of free radicals capable of oxidizing ethyl alcohol to acetaldehyde leading to oxidized aromas. In addition, free radicals are capable of rapidly oxidizing SO2 and thiols, leading to a disappearance of the aromatic forms, resulting in a loss of aromatic freshness.
Both targeted clarification and the use of yeast derivatives and tannins can be used to manage oxygen-related issues.
Oxidation management can have a curative approach, i.e., removing oxidized compounds and the reduction of yellow hue (O.D. 420nm), indicative of oxidative evolution of must and wine; or a preventive approach, intervening early by preventing potential oxidation reactions.
Enartis offers a winning strategy to protect your wine. Our targeted products work in synergy to prevent spoilage, preserving the aromatic richness and quality of your wine.
Catechins are not the only polyphenols responsible for oxidation.
It should not be forgotten that there are other compounds that tend to oxidize very rapidly once exposed to oxygen, such as phenolic acids: hydroxybenzoic and hydroxycinnamic, including caffeoyltartaric acid and para-cumaroyltartaric acid. The resulting quinones are responsible for darkening must and subsequent loss of aromatic quality.
Inactive yeast are also known to be viable alternatives for protecting wine from undesirable oxidative mechanisms. In fact, they contain natural antioxidant compounds, such as glutathione and mannoproteins, that neutralize free radicals responsible for oxidation. They can also chelate metals responsible for oxidative reactions.
EnartisPro BLANCO is a yeast derivative rich in readily soluble mannoproteins. Addition during pre-fermentation and fermentation releases sulfur amino acids that protect aromatic compounds from oxidation, thus, resulting in wines with a younger, more intense, and fresher color tone.
Enartis has developed a targeted strategy to provide protection over time, even after alcoholic fermentation.
EnartisTan SLI is a tannin extracted from untoasted American oak using a unique process that avoids exposure to high temperatures. This enables it to maintain high antioxidant efficacy capable of stabilizing redox potential and preventing oxidation and the possible appearance of reduced odors as early as the end of alcoholic fermentation.