Each step of the wine making process; from crushing grapes, various stages of fermentation, even the quiet, gentle racking; produces various amounts of solids that must be removed to produce the sparkling and polished elixir we expect.
In 1857, Louis Pasteur developed a scientific technique for wine making that continues in use today by commercial and amateur wine makers.
Some commercial wineries who do not worry about “bruising the wine” and effecting the flavor, will force the wine, under pressure, through filters to remove any remaining suspended matter.
Finings or Wine Clarifiers
Fining with Gelatin
If your wine seems unusually cloudy at some point during a secondary fermentation, one teaspoon of unflavored gelatin will usually clear about 6 gallons of wine. Soak gelatin in one pint of wine drawn from the fermentation vat, heat the gelatin to 180-degrees F. Stir this solution into the bulk of the wine until well mixed, replace the fermentation lock and let wine sit undisturbed for 10 days. All of the sediment should have settled and you will be able to rack off clear wine. Gelatin will not serve as a clarifier if the wine fails to have enough tannin to make the gelatin flocculate and settle. The addition of tannin purchased from the wine maker’s shop is an easy solution.
Fining products are available at most wine maker’s shops. Read the package instructions and select the one that best suites your needs.
Tips and Warnings
Closely follow manufacturers quantity instructions, or recipe, for the finings you choose. If you use too much, some finings will bleach the color from the wine. Also, excess finings can remain in suspension, leaving the wine more cloudy than when you began.
Otherwise, when fermentation is finished, wine is treated with “finings” or clarifiers like bentonite clay, gelatin, or isinglass which precipitates out any remaining suspended matter.
Usually, if the wine is cloudy, fining will correct the problem. The finings, mixed with wine, will slowly attach themselves to the solids and carry them to the bottom of the vat.
Finishing the wine
Fermentation is complete, the wine glistens and entices, and it is time to make final decisions about the fate or your batch of wine.
Most wine is bottled and aged for varying periods of time.
Brandy or other distilled spirits are added to produce fortified wines and aperitifs.
Sparkling wines are usually made at this point.
High quality red wines are ready to be aged in oak barrels.
These are all possibilities for the home wine maker once you have mastered the art of producing a clear and polished bottle of wine.