After two more days, I am ready to stop fermentation.
My wine tastes mindblowingly perfect. At 1.020 specific gravity, I have 10% alcohol and 2.5% residual sugar: as mathematically pure and balanced as the Parthenon, the Fibonacci Sequence and espresso.
In truth, I am not sure if I can kill the yeasts. To hedge my bets, I want to start early. I like where the wine is. But will it taste disgusting if allowed to ferment dry? Acidity and alcohol are inching their way into the fore and might overwhelm the present fruit.
The plan: siphon the juice into the clean glass carboy, kill the yeasts with potassium sorbate, and stop spoilage with potassium metabisulphite.
If that fails, I have to freeze seven gallons of fermenting juice somehow in order to halt the yeasts. Failing that, I will have to drink a dry vignoles, or go German and add my secret gallon of unfermented juice from the fridge (i.e. süssreserve). Enough talk, time to siphon the lot:
Onto murder some yeasts.
First, I add potassium sorbate (one gram per gallon) to the fermenting must. This salt comes from the berries of mountain ash trees. Once in the wine, the sorbate salt becomes sorbic acid, which is volitile to yeasts. It will stabilize the wine by, ahem, aborting any future yeasts. Not a pleasant thought, but the single parents, newly neutered, will die naturally and never multiply again.
Hmmm….oddly fizzy. But no matter.
To keep my meta levels…level, I need to also add potassium metabisulphite. The sulphite will strengthen the sorbic acid to keep bacteria at bay. If there was no sulfite, the wine would go into malolactic fermentation, wherein bacteria would convert the sorbate into geraniol (aka hexadienol), which smells of rotten geraniums and trout. I do not like trout or geraniums. So in it goes…just as my wife wakes up…
“Smells nice”…so will the carpet.
How the hell did I create a science fair volcano? Fallbright had given me a only paragraph on stabilizing wine. It said to add both sorbate and sulphite “at the same time.” The internet told me the same. I could have waited until fermentation ended, just before bottling, but no one mentioned exploding carboys and ruined carpets.
Basically, adding potassium sulphite was like giving the sorbic acid steroids. I should have held off on the sulphite until the fizzing stopped.
Vesuvius killed my pride, but the wine tastes the same. It is all I have. So I press on.
While cleaning the carpet, I plot how to cold stabilize the yeasts to ensure they never come back.