Is L Cysteine Safe?
L Cysteine is the additive E920 — a dough improver that can be made by fermentation — but is traditionally derived from feathers or hair, so source matters for vegans and halal consumers.
Is L Cysteine safe to eat?
E920 is considered safe. It is authorised across the EU, UK and US, and safety evaluations by the European Food Safety Authority (EFSA) have not identified health concerns at the levels used in food. For most people there is no reason to avoid E920.
EFSA status: Authorised in the EU — no safety concern at current levels of use
Source: European Food Safety Authority
What is L Cysteine?
E920 is the E-number for l-cysteine, one of the flour treatment agents group of food additives (E900–E929). Additives in this group improve the baking quality and handling of flour and dough. An amino acid that can be produced by fermentation, but is traditionally derived from feathers or hair. L-cysteine has one of the least appetising origin stories in food: it was traditionally extracted from duck feathers, hog hair or even human hair. Modern production increasingly uses fermentation, but the label won't tell you which. Like every E-number, E920 has been evaluated and authorised for use in food in the European Union — the 'E' literally stands for Europe, and a number is only granted after a safety assessment. That authorisation doesn't mean every additive suits every diet or that all concerns are settled, which is why we break down the safety, vegan, vegetarian and halal status of E920 in detail below.
What foods contain L Cysteine?
E920 (L Cysteine) is typically found in:
- Commercial bread and rolls
- Pizza bases
- Bagels
- Baked goods
Frequently Asked Questions
Is L Cysteine bad for you?
Yes. E920 is authorised in the EU, UK and US, and EFSA evaluations found no health concern at normal food levels.
Is L Cysteine vegan?
E920 is uncertain for vegans — it is an amino acid that can be produced by fermentation, but is traditionally derived from feathers or hair, and the label doesn't reveal the source. Look for a vegan certification or ask the manufacturer.
Is L Cysteine halal?
E920 is mashbooh (doubtful) — an amino acid that can be produced by fermentation, but is traditionally derived from feathers or hair. Verify the source with the manufacturer or choose halal-certified products.
Full guide to E920 (L-Cysteine) →
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Additive data sourced from Open Food Facts (ODbL licence) and the European Food Safety Authority (EFSA).