What it is
Strong alkali used to make pretzels brown, cure olives, hull hominy and give ramen its bite — neutralised or rinsed out before you eat it.
Why your biology objects
Caustic in the bottle, but it's a transformation tool, not a residue — the finished food carries no free lye. And alkaline processing is deeply ancestral: nixtamalizing corn with wood-ash lye unlocks its bound niacin, a 3,000-year-old technique, and potash was the original leavening. The alkali does the work, then leaves.