Blackberries, blackcurrants and raspberries make particularly good fruit vinegars.
Usual method: Wash the fruit, place in a bowl, and break it up slightly with the back of a wooden spoon. To each lb. of fruit allow 1 pint malt or white wine vinegar. Cover with a cloth and leave to stand for 3–4 days, stirring occasionally. Strain through double muslin and add 1 lb. sugar to each pint. Boil for 10 minutes, cool, strain into sterilized bottles and cork.