If a wine has undergone unwanted malolactic fermentation (MLF), there are several signs that can help you identify this issue:
- Buttery or creamy texture
- Loss of fruity or fresh aromas
- Increased levels of diacetyl
- Lower levels of acidity
- Unbalanced flavors
Buttery or Creamy Texture
One of the most noticeable signs of unwanted MLF in wine is a buttery or creamy texture. This is caused by the production of diacetyl during malolactic fermentation, which can give the wine a rich and smooth mouthfeel.
Loss of Fruity or Fresh Aromas
Another common sign of unwanted MLF is the loss of fruity or fresh aromas in the wine. Malic acid, which is converted to lactic acid during MLF, plays a key role in preserving these aromas. If MLF occurs unintentionally, it can lead to a reduction in the wine’s fruitiness and freshness.
Increased Levels of Diacetyl
Diacetyl is a compound produced during malolactic fermentation that can contribute to buttery or butterscotch flavors in wine. If a wine has undergone unwanted MLF, you may notice higher levels of diacetyl, which can overpower other flavors and aromas.
Lower Levels of Acidity
Malic acid is a primary source of acidity in wine, and its conversion to lactic acid during MLF can result in a decrease in overall acidity. Wines that have undergone unwanted MLF may exhibit lower levels of acidity, leading to a flat or flabby taste.
Unbalanced Flavors
Lastly, unwanted malolactic fermentation can lead to unbalanced flavors in wine. The conversion of malic acid to lactic acid can shift the wine’s flavor profile, making it less harmonious and potentially masking the true characteristics of the grape.