"Campden Tablets (KMS)" contain about 450 mg of potassium metabisulphite. These are added crushed and are used as sterilizing agents. The usual rate is two tablets per gallon for sterilizing the must; the same at the first racking; and one tablet at successive rackings.
50 grams (1.8 oz.)
DIRECTIONS: Add 1 tablet per gallon (4L) of fruit must to sterilize fruit and minimize oxidation.