This "White stuff", called Sodium Percarbonate, has amazing benefits for Sanitising and Cleaning a huge range of Household Surfaces, including of course, our Home-brewing Equipment. Areas to be sanitised with this Environmentally Friendly Product may include; Kitchen Surfaces, Chopping Boards, Bathroom Showers, Bathroom Furniture, Walls and Floors. Effective also as a Carpet and Laundry Stain Remover, this Cleaner/Sanitiser is an Odourless, Colourless, Non -Toxic Non-Bleach, Chlorine Free Product that makes stains simply "Vanish" with minimal effort.
Sounds good enough to drink? . . . . . Sodium Percarbonate is not recommended for use in drinking water although the minimal amount of residue left after sanitising your Barrels and Equipment is perfectly OK.
Hint: Be sure to use separate cloths for sanitising your Homebrew equipment and wiping down the bathroom furniture!