Is L-Cysteine vegan?
Depends· E920
L-cysteine is often made from human hair, duck feathers or pig bristles — but a synthetic vegan version exists.
Also known as: cysteine, E920
What it is
An amino acid used as a dough conditioner in bread and bagels.
Why depends
Conventional L-cysteine is rendered from hair and feathers. A bacterial-fermentation version (Ajinomoto's process) is vegan, but labels rarely specify the source.
Where you'll find it
- Commercial bread
- Bagels (notably Einstein Bros, some Subway breads historically)
- Pizza dough
- Pre-packaged pastries
Vegan alternatives
- Breads made with ascorbic acid as a dough conditioner instead
- Home-baked or bakery sourdough
FAQ
- How do I know if a bread's L-cysteine is vegan?
- Contact the manufacturer. Brands like Dave's Killer Bread state they use synthetic L-cysteine; many do not disclose.