Malt Vinegar (using liquid or dry malt extract)
Dry or liquid malt extract (type can be personal preference though barley based ale extracts approximate traditional recipes)
Brewing yeast (ale or lager)
Live mother of vinegar
Mix quantity of extract with water to adjust the specific gravity for 6% alcohol by volume (roughly 1.05). For liquid yeast, pitch in directly. For dry yeast, soak in lukewarm water for 15 minutes and then pitch in. Do not add hops. Keep in a warm place and allow alcoholic fermentation to proceed to completion (when bubbling stops and specific gravity is 1.0). Add mother of vinegar of 1/5 of the volume of the ale. Cover tightly with cheesecloth or another covering to allow air in but to prevent fruit flies from entering the fermenting vinegar. Place in a warm (25 – 30 C; 75 – 80 F) place away from sunlight for one to three months. A thick mother should form on the surface and an increasingly acidic smell should develop over time. Testing with a pH meter can guarantee safety once pH is below 3.5 but acidity can only be measured by sodium hydroxide titration. The vinegar should be at least 4% acidity before use. Once the vinegar reaches 4.5% acidity, you can stop and it is important to measure acidity frequently after this point since allowing fermentation too long can cause bacteria to metabolize the vinegar and begin lowering acidity. Make sure the vinegar reaches 5% before using in canning.
Titration can often be done at a wine lab if unfamiliar with the process. Once done, put the mother with enough vinegar to submerge it completely in an airtight, twist top container for preservation and future use. For the finished vinegar, you may bottle and use at will. If pasteurization is desired to prevent future fermentation pasteurize it on a stove in a stainless steel pot at 65 C (150 F) for 15 minutes.
For added flavor and color similar to Sarson’s malt vinegar, add liquid malt extract to the final vinegar to adjust specific gravity to 1.015.
Malt Vinegar (All grain recipe)
Obtain milled malted barley grains and heat and sparge/mash as with regular wort preparation in order to reach a specific gravity of 1.06. Then follow the instructions past pitching the yeast in the previous recipe.