Vinegar is usually produced by simply allowing cider to stand in barrels with the bung hole open, until the second or third acetous fermentation is completed. It requires several months for the process to be finished, the time varying considerably with the degree of temperature. Cider has a refrigerated shelf life of about 2 to 3 weeks at 32-36 degrees F. McIntosh is the main cider apple used in Vermont. Most modern cider is made with a blend of varieties. Apple cider may be frozen for up to a year without loss of quality.
Apple cider is a good source of pectin.