This is a first-timer’s batch. To make vinegar in larger quantities for more gifts, use a 5-gallon food-safe container. Whatever vessel you use, never fill it more than halfway to allow air to circulate. For best results, choose a wine with low alcohol and no added sulfites, and an unpasteurized starter vinegar like Bragg apple cider.
- 2 750-ml bottles red wine, preferably 10%–12% alcohol by volume
- 1⁄2 cup unpasteurized apple cider vinegar
- In 2 half-gallon canning jars, divide the wine. Add ¼ cup vinegar and ½ cup water to each. Cover tightly with a lid and shake vigorously for 30 seconds. Remove the lids and place a paper towel over each jar. Screw the rings on top to secure, or use a tight-fitting rubber band.
- Label the jars with a start date and store in a dark place, ideally 68°–75°. For the next 2 days, replace the lids and shake each jar once a day. Cover with a paper towel after each time. After that, let rest with the paper towel for 2–3 weeks or up to 2 months, tasting with a clean spoon after 1 week and intermittently throughout. If too strong, dilute with up to 1 cup water and shake vigorously every other day.
- Transfer vinegar to smaller, airtight bottles for giving if desired. Continue to store in a cool place for 6–8 months.