Halal Additive Checker
E920

L-Cysteine

Is it halal?

That depends on the source used, which is why this page states the source rather than a verdict:

Varies by manufacturer

Can be made from either plant or animal fat, including pork, depending on the producer. The label rarely says which, so a halal mark or a written answer from the manufacturer is what settles it.

Historically produced from feathers, hog bristle or human hair. Today most is made by bacterial fermentation, but not all. In bread it is common enough to be worth checking.

Found in
Bread, bakery dough conditioner

Others from the same source

This page describes what additives are made from. It does not issue rulings. Where a source varies by manufacturer, the only reliable answer for a specific product is its halal certification or the manufacturer’s own statement — and where the schools of law differ, the position of the school you follow is the one that answers your question.