One of the strangest remedies we have ever heard of involves sauerkraut juice against canker sores. Take a tablespoon of sauerkraut juice in your mouth and swish it around morning and night, then swallow it. Do this twice a day and the canker sores should go away. We first heard about using sauerkraut juice to treat canker sores from D.W. in Garland, Texas. His mother had been a dental assistant in the 1930s. Since then we have heard from many people that it can provide rapid relief. One physician who benefited personally arranged for analytical testing of sauerkraut juice and discovered a number of active compounds that may be responsible for its healing properties.