L-Cysteine E920
dough conditioner — Primarily synthetic or animal-derived.
L-2-amino-3-mercaptopropionic acid
CAS: 52-90-4
Factual Regulatory Reference
This database provides factual regulatory information compiled from official government sources. It does not constitute medical, nutritional, or safety advice. Regulatory status varies by country and is subject to change. Always refer to your local regulatory authority for the most current information.
? Did You Know?
L-Cysteine occurs naturally in Meat, poultry, eggs and Dairy products. Many people consume it daily without realizing it's also a listed food additive.
L-Cysteine is produced through fermentation — the same biological process used to make bread, beer, and yogurt.
Beyond food, L-Cysteine is also used in cosmetics, medicine, industrial applications, household products. Its versatility makes it one of the most multi-purpose chemical compounds in everyday life.
Detailed Regulatory Assessment
European Union (EFSA)
Banned as food additive since 2004
United States (FDA)
Approved as dough conditioner, up to 90 ppm in flour
Japan (MHLW)
Approved as flour treatment agent
Acceptable Daily Intake (ADI)
International Standard (JECFA)
mg/kg body weight per day
European Standard (EFSA)
Everyday Perspective
For a 60kg adult, this limit is roughly equivalent to consuming:
Natural Occurrence
A sulfur-containing amino acid that occurs naturally in proteins. Used in bread-making to break down gluten proteins, making dough more pliable and reducing mixing time.
Manufacturing
Historically extracted from human hair (China) or duck/poultry feathers. Modern production primarily uses bacterial fermentation (E. coli) or chemical synthesis. Hair and feather sources have been phased out in most regions.
Applications Beyond Food
Hair permanents, skin whitening products
Antioxidant supplements, mucolytic agent (N-acetylcysteine)
Flavor enhancer (meat flavoring)
Dietary supplements for skin and hair health