Achieving Cold Stable Wines
Don Catharine — Burnt Hills, New York asks,
In your article “Malolactic Fermentation After Cold Stabilizing” https://winemakermag.com/wine-wizard/malolactic-fermentation-after-cold-stabilizing you mention that malolactic fermentation (MLF) may start back up after cold stabilizing when the wine warms back up.
For me, as in your article, MLF was underway albeit somewhat slowly; I believe because the pH of the different wines was running low, ~3.2–3.3 and ~11% ABV. I didn’t want to miss the window of cold nights in my upstate New York garage, so mid-February I placed the carboys out in the garage. After One month I brought them back inside. The next day I performed a chromatography test to verify MLF was not complete. I then added 1⁄2 the recommended dose of Opti-Malo Plus and stirred it in gently. I did not rack the wine because I was concerned about subjecting the wine and MLF bacteria to oxygen.
• Should I have racked the wine?
• Should I be concerned that some of the tartrate crystals that have fallen out will be mixed back into the wine or will they remain as crystals never to become part of the solution again?
• How concerned should I be about subjecting the MLF bacteria to atmosphere? I can purge the carboys with CO2 if you think that would help.