This is a non-essential amino acid added to many baked goods as a dough conditioner in order to speed industrial processing. It’s usually not added directly to flour intended for home use, but you’ll find it throughout commercial breads such as pizza dough, bread rolls and pastries.
The hair is dissolved in acid and L-cysteine is isolated through a chemical process, then packaged and shipped off to commercial bread producers. Besides human hair, other sources of L-cysteine include chicken feathers, duck feathers, cow horns and petroleum byproducts.
Most of the hair used