Inhibition of Bacteria Occurring in Wine Production

Malolactic fermentation occurs during wine production. Malolactic Fermentation is the result of the decarboxylation of L-malate to L-lactate by malolactic bacteria. The most important bacterial species in the malolactic fermentation process is known as Oenococcus oeni.

The secondary fermentation process in this fermentation cycle is very difficult to control. Uncontrolled MLF during this fermentation process occurs in viticulture areas with warmer climates compared to standard regions. The pH level of wines produced in these areas is high. Consequently, the wines become tasteless. It also leads to the spoilage of the wines.

To prevent the inefficiency and spoilage in product quality occurring during these processes, Malolactic Fermentation must be stopped after a certain point. For this, the reproduction of Oenococcus oeni bacteria must be reduced or halted.

What is the Cause of Wine Spoilage?

The most important cause of wine spoilage is the failure to determine whether the Malolactic Fermentation process has concluded in wines placed in oak barrels for aging in regions with warm viticultural conditions and lower malic acid levels.

This is because malolactic fermentation must occur to a certain extent in wine production. However, if a fermentation process occurs beyond the required malolactic fermentation, it causes undesirable organoleptic reactions and a significant loss of red color in the wine.

What is the Effect of pH on Wine Spoilage?

pH control in wine is very important. Because every bacterium has a tendency to reproduce within a specific pH range. In wine production, a pH level of 3.3 and above generally causes very few problems. At lower pH ranges, some issues arise in wine production.

O. oeni bacteria are a type of bacteria that is more active below pH 3.5. In wine production, the pH level highly affects the activity of malolactic fermentation.

In the event that cells are exposed to acid shock during wine production, the concentration of O. oeni increases due to the increase in stress proteins.

What is Used to Prevent Malolactic Fermentation?

Inducing malolactic fermentation can generally be difficult. At the same time, preventing the growth of Lactic acid bacteria is equally difficult. Malolactic fermentation is inhibited with Fumaric acid. Additionally, it becomes unstable when metabolized by lactic acid and yeast bacteria.

Lysozyme, an approved and reliable substance, is an important preservative in wine production. Its cost is high.