Along with eggs, I've used previously unopened sour cream WAY (, way) past the date and do the same as you once it's opened. Between the pasteurization of the original milk and then innoculation with good microbes, the lower moisture content and the acidity, it's not a very hospitable environment for pathogens.
Cauterization definition, to burn with a hot iron, electric current, fire, or a caustic, especially for curative purposes; treat with a cautery. See more. Dictionary.com
Cauterization is an ancient medical practice that is still in use currently. It involves creating burns on body tissue to either close wounds or stop bleeding, or to remove part of the body. People are most likely to think of medical doctors using this practice long ago to apply hot metal after amputation.