Viognier Malolactic Fermentation
Most reds and full body white wines go through malolactic fermentation (MLF). This is a process where naturally occuring Lactic Acid Bacteria (LAB) will convert malic acid into lactic acid. Malic acid has a sharp, crisp, green-apple tartness, while lactic acid has a milder, creamier, and buttery sourness such as found in yogurt. The benefit of MLF is the resulting wine is more stable as it can not undergo spontaneous MLF if there is no malic acid present, which would carbonate the wine and pop corks.
Lack of Spot in Paper Chromatography Test Indicates Less than 100 mg/L Malic Acid
This second season vinifying the ‘22 Walla Walla Viognier seemed just as stuborn completing MLF. The reds completed MLF in a timely manner of about 1 month. The Viognier on the other had did not complete until the end of summer, I think it was the August heat wave helped it complete. After it was suspected complete (I was busy bottling), I left it so the diasydal got consumed. Dyasydal is the buttery taste in a oaky Chardonnay and is a by product of MLF depending on the strain of LAB selected.