Vinegar by John Spottiswood.

vinegar Cooks use vinegar to make pickles, deglaze pans, marinate meats, and add tang to vinaigrettes, sauces, and even desserts. Vinegars are made by adding a bacteria called Acetobacter aceti to diluted wine, ale, or fermented fruits or grains. This creates acetic acid, which gives the liquid a sour flavor. Unopened, most vinegars will last for about two years in a cool, dark pantry. Once opened, vinegar should be used within three to six months.