It explains the chemical reaction known as saponification, where fat reacts with lye to produce soap and glycerin. Carl's homemade soap undergoes a week-long curing process before testing its ...

These oils are mixed together to form soap through a chemical reaction called saponification. Then essential oils like peppermint and lavender are added. The final soap is cooled before it's bottled.

Lamb, MD, from Mount Sinai Hospital in New York. Dr. Angela Lamb: So what shampoos do mostly is they do what's called saponification. So the actual shampoo comes along and wraps around oil and ...