Last reviewed May 2026 · 1 min read
Is L-Cysteine vegan?
Also known as: E920, Cysteine
E-number: E920
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Source can be plant or animal.
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It depends — It can be synthesized synthetically or from microbial fermentation (vegan), but is traditionally extracted from poultry feathers or hog hair (non-vegan).
01 · The basics
What is L-Cysteine?
An amino acid used primarily as a dough conditioner to speed up industrial baking and improve bread texture.
02 · The source
Where it comes from
It can be synthesized synthetically or from microbial fermentation (vegan), but is traditionally extracted from poultry feathers or hog hair (non-vegan).
03 · Alternatives
Best vegan alternatives
Synthetic L-cysteine
Check Price on AmazonAscorbic acid (Vitamin C) as a dough conditioner
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Frequently asked
FAQ
Is L-Cysteine made from human hair?
Historically, it was extracted from human hair sourced from barber shops, but this practice is now banned in the EU and US. Today, duck feathers are the most common animal source.
How do I find vegan bread?
Look for artisan bread (flour, water, yeast, salt) or check the packaging for a certified vegan logo, which guarantees no animal-derived E920 was used.
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A firming agent and acidity regulator.
Chitin
A fibrous substance consisting of polysaccharides, used in agriculture, winemaking, and dietary supplements (for weight loss).
Chitosan
A linear polysaccharide derived from chitin, heavily marketed in supplements as a 'fat binder' for weight loss.
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Related ingredients
E422 (Glycerol / Glycerin)
A sweet, syrupy liquid used as a humectant in foods and cosmetics.
E920 (L-Cysteine)
A dough conditioner used in commercial bread baking.
Calcium Carbonate
A common mineral used as a white food coloring, an anti-caking agent, and a calcium supplement.
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