Miscellaneous additive
Is E920 (L-Cysteine) halal?
The additive that makes commercial bread dough workable. Its cheapest historical source was human hair — which is why this otherwise obscure amino acid has a whole fiqh discussion attached.
A dough conditioner with four possible sources. Human hair and porcine bristle are haram; synthetic is halal; poultry feathers from halal birds are accepted by some scholars and rejected by others. JAKIM requires source documentation.
What we know
Named sources are on this page. Classification: Source-dependent.
What we don’t know
The pack in your hand does not, by itself, name the raw material or process.
Why it matters
Doubtful until the source is known (mashbooh)
What to verify
For E920 in this product: is the source plant, synthetic, or animal? If animal, which species and slaughter method?
The detail
L-Cysteine is an amino acid used to relax dough in industrial baking. MuslimConsumerGroup documents the source hierarchy: haram from human hair, halal from synthetic material, and genuinely disputed when from chicken or duck feathers — one school of ulema accepts it, another does not. HalalExpo's checker records the JAKIM position: human hair haram, porcine haram, poultry feathers from halal birds halal, synthetic halal, with source documentation required. IFANCA lists cysteine hydrochloride among doubtful bagel ingredients. Modern Western industrial supply has shifted heavily toward fermentation and synthetic routes, but 'shifted' is not 'documented' — the label still does not say.
What the sources say
Mushbooh, Haraam if it is obtained from human hair, Halal if it is made from Halal synthetic material. The third source is from chicken/duck feathers. There is difference of opinions among different Islamic scholars.
JAKIM requires source documentation. Human hair = haram. Porcine = haram. Poultry feathers from halal birds = halal. Synthetic = halal.
Bagel — Cysteine Hydrochloride, Enzymes, Folic Acid, Niacin
Where you will run into it
- Commercial bread and bagels
- Pizza dough
- Tortillas and wraps
- Pastry and croissant dough
How to check it yourself
A halal-certified bakery product settles it. Otherwise ask the manufacturer for the L-cysteine source: synthetic/fermentation is the answer you want. Feather-derived splits scholarly opinion — defer to your own school.
What to ask the manufacturer
A recognised halal mark or a vegan declaration can settle this instead. If you email the brand, send one specific question:
For E920 in this product: is the source plant, synthetic, or animal? If animal, which species and slaughter method?
Quick facts
| E-number | E920 |
|---|---|
| Name | L-Cysteine |
| Also on labels as | l-cysteine, cysteine, l-cysteine hydrochloride, cysteine hydrochloride, e921, L-cysteine |
| Additive class | Miscellaneous additive |
| Classification | Source-dependent |
| Source last accessed | 2026-08-21 |
Common questions
Is E920 (L-Cysteine) halal?
L-Cysteine is classified as Source-dependent. A dough conditioner with four possible sources. Human hair and porcine bristle are haram; synthetic is halal; poultry feathers from halal birds are accepted by some scholars and rejected by others. JAKIM requires source documentation.
Is L-Cysteine halal or haram?
On the evidence cited on this page, L-Cysteine is source-dependent. Doubtful until the source is known (mashbooh) Every position is attributed to a named certifier or scholarly body with a link, so you can verify it directly.
What else is L-Cysteine called on ingredient labels?
It can appear as: l-cysteine, cysteine, l-cysteine hydrochloride, cysteine hydrochloride, e921, L-cysteine.
Why isn't there a single yes/no answer for E920?
Because the ruling depends on information the label does not carry — the source material, the production route, or which scholarly position you follow. This page shows each named position with a link so you can check it yourself.
Where does this page's information come from?
Every position on this page is attributed to a named certifier or scholarly body with a direct link, listed under 'What the sources say'. Muttoo aggregates and cites; it does not issue rulings.
Related lookups
Record e920-l-cysteine · report an error