“In Soap Making: Lye is mixed with water to create a lye solution. Lye solution, when mixed with fats and oils, will cause a chemical reaction called saponification (fancy for soap). The result of saponification is beautiful handmade soap.
Food uses of sodium hydroxide include washing or chemical peeling of fruits and vegetables, chocolate and cocoa processing, caramel coloring production, poultry scalding, soft drink processing, and thickening ice cream. Olives are often soaked in sodium hydroxide for softening; Pretzels and German lye rolls are glazed with a sodium hydroxide solution before baking to make them crisp.“
Philbert