Success in making apple cider vinegar at home is dependent on three factors: good yeast, supplying enough oxygen to the mixture by stirring and maintaining a stable temperature between 60 and 80 degrees. Lower temperatures do not reliably produce a good vinegar; higher temperatures interfere with the action of the yeast. You do not have to use a starter yeast, but the fermentation will take longer and be less reliable without it. Use a special vinegar yeast, called a “mother”, to start the vinegar. You can find vinegar mother yeast at brewer’s supply stores. Do not use baker's yeast.
Always use a glass, plastic, enamel or stainless steel containers for making vinegar. Aluminum and other reactive metals will corrode in the acid environment.
Make or purchase a good quality fresh cider made from fall apples. Thoroughly wash the apples, crush the pulp and strain the juice through cheesecloth.
Crumble 1 cake of vinegar yeast into 1 quart of cider to make a yeast starter for 5 gallons of vinegar. If making more or less than 5 gallons of vinegar, made a proportionate amount of starter.
Mix the starter with cider to make 5 gallons. Mix well and pour into containers, approximately 3/4 full. Place the lids loosely on the containers, but do not seal.
Store the containers at 60 to 80 degrees F for 3 to 4 weeks, until the fermentation is complete. Stir or shake the containers daily to oxygenate the cider.
Taste the vinegar when you begin to notice a vinegar smell. Taste a sample daily until the vinegar reaches the desired strength.
Filter the vinegar through a coffee filter to remove the sediment. Use immediately or pasteurize for long-term storage.
Pasturize the vinegar by heating it to between 140 and 160 degrees before pouring the vinegar into sterilized jars and sealing the caps.