Interesting Food - Bread

L-Cysteine is an amino acid used to prolong shelf-life in commercially produced bread.

(It can be found in duck and chicken feathers and cow horns, but most of the L-Cysteine used in food production comes from human hair.

Most of the hair used to make L-Cysteine comes from China, where it's gathered from barbershops and hair salons. You can avoid L-Cysteine baking your own bread, as it is not an additive in flour, but if you find the idea of eating other people's hair, steer clear of fast food places such as McDonald's, Dunkin' Donuts and Burger King, who allegedly use L-Cysteine as an additive too.)