Where you choose to ferment your wine is one of the most important decisions you can make to ensure a good, thorough fermentation. A consistent temperature within the range of 65 – 75 degrees F. will work with all of the yeasts we sell here at Walker’s. Also, the wine should not be exposed to direct sunlight for any length of time as that could cause your wine to brown. Since heat rises, elevating your containers off the floor may be a better option if you choose to ferment in a cooler environment.
As you make more and more wine, and begin experimenting with your own blends and styles, it can be very helpful to start collecting various size containers. Gallon and half gallons, especially, prove to be useful for drawing off prior to fermentation, and for making smaller trial samples from larger batches. Sweetening a gallon of wine and then bottling can be easier and more consistent than doing several bottles individually.
How your wine ferments depends on a number of factors: juice, yeast, temperature, sulfites, etc. Monitoring your airlock can give you a good visual idea of how your wine is doing. Using plastic wrap and a rubber band on the small jug of wine you drew off can help keep fruit flies from getting to your juice as it ferments. Also, clear containers such as carboys allow you to see how the fermenation is proceeding through the various stages. Keeping good records each year can help you eliminate problems that may occur in your winemaking procedures.
Periodically, you may notice bubbles while siphoning. It is generally the result of fermentation, or excess SO2 gas bound-up in your wine. This condition can be dealt with fairly easily, and should not be considered a wine fault. Sometimes, “splash racking” your wine into another container will remove the excess gas. If a slowed, or renewed fermentation is occuring, letting your wine finish fermenting may be the best course of action. When this happens in the bottle, it usually indicates the wine was bottled before fermentation was completed.
The “lees” or sediment is created during fermentation by dead yeast cells and other particles settling to the bottom of your container. The commercial yeast strains available can create a compact layer making it easier to rack your wine without drawing much of the sediment into the siphon tube. In some instances, unusual looking formations can occur along with normal settling. These can be due to particles of tartaric acid dropping out of your wine along with the sediment.
Tartaric acid, the dominant acid found in grapes, helps give wine its tartness. In instances where the beginning acid in your juice is high, you may observe tartrate crystals forming on the bottom of the carboy, along with the lees, during fermentation. Also, excess tartaric acid can be forced to precipitate by putting your nearly finished wine through a cold stabilizing process. Lowering your wine’s temperature to between 28 – 30 F. for two to four weeks can help excess tartaric acid settle out more quickly assuring it won’t form naturally, over time, in the bottle.
The earth’s atmosphere abounds with all kinds of yeast, molds and bacteria. This juice has been inoculated with the proper amounts of Potassium Metabisulfite to eliminate the wild yeast and any other undesirable organisms in the juice. By using wine yeast, you will be able to easily control the fermentation in your wine.
A basic fact of chemistry is that alcohol plus oxygen yields acetic acid or vinegar. Therefore, always keep air away from wine after the initial violent fermentation.