by Crockof... on Sun Aug 18, 2013 1:08 pm
Hi Paul,
Temperature is always a variable. Based on making wine vinegars, starting with 50 - 60 litres of fresh wine it usually takes 6 months to a year depending upon the depth of flavour you are interested in. Removing about 80% of the remaining liquid volume, leave the mother and provide more beer to feed her. Again, I am not certain the same rules hold true for a malt vinegar.