Combine the wine and water and expose the combination to air 24 hours prior to the fermentation process. Add a piece of the mother of vinegar to the water and wine combination and mix it in thoroughly to start your vinegar. Pour the mixture into Mason jars. Cover the open jars with paper towels and secure with rubber bands. The covering protects the mixture from contamination from airborne vinegar flies and vinegar eels. The insects would otherwise feed on the mother of vinegar that occurs in naturally fermenting vinegar. Place the jars in a warm, dark place between 74 to 86 degrees. It can take roughly one to six weeks to convert the alcohol to acetic acid; the time will vary depending on the temperature. The "wash," or weak, alcoholic liquor, will ferment slowly. As you check it during the weeks to follow, judge the strength by its taste until it reaches a taste you like. When the vinegar begins to weaken in flavor, it is done. Pasteurize the vinegar by heating it to at least 140 degrees; hold this temperature for 30 minutes, routinely checking it with a cooking thermometer. Filter the young vinegar through coffee filters into sterilized bottles using a funnel. The vinegar preserves itself and will not require refrigeration. Store at room temperature and out of the way of direct sunlight for six months. Storing the vinegar is a crucial step in achieving the ultimate smoothness and quality. After the alcohol is turned to vinegar, you can age it to improve its taste.
- This fermented mixture gives an acetic acid concentration of 5 percent.