What alternatives for wine acidity do we have in the frame of climate change? Fumaric acid is already used for pH adjustments both in must and in wine in USA and New Zealand, but what is the microbiologial action of fumaric acid?
This video extract was taken from Pierre Louis Teissedre’s lecture presented at the 18th edition of Enoforum (Vicenza, May 16-18, 2023) “Alternatives for wine acidity in the frame of climate change: the case of fumaric acid as new oenological practice”
You can find the full recording at this link
OIV recognition: in 2021, the OIV approved fumaric acid for inhibiting malolactic fermentation in wine, addressing stability concerns and reducing reliance on sulfur dioxide.
Objectives of fumaric acid use: the primary goals include controlling lactic acid bacteria responsible for malolactic fermentation, preserving malic acidity, and reducing sulfur dioxide doses.
Recommended dosage: optimal control is achieved with 300-600 mg/L of fumaric acid, effective even in wines with high inoculum levels and during tumultuous fermentation.
Mechanism of action: fumaric acid exhibits antimicrobial activity beyond its typical intracellular dissociation, likely involving additional mechanisms, such as the GAD system that converts glutamate to GABA, raising intracellular pH.
Research findings: studies led by Professor Antonio Morata show that 300 mg/L fumaric acid maintains stable levels of malic and lactic acid, ensuring microbial stability without altering wine acidity.
Efficacy at various concentrations: while 300 mg/L shows effectiveness, higher concentrations up to 600 mg/L offer enhanced control, especially in wines with high bacterial counts.
Application in wineries: Fumaric acid is now employed as a reliable means of halting malolactic fermentation within 48 hours, providing winemakers with an alternative to traditional acidifiers like tartaric acid.