Computed from named public guides — NOT independently scholar-ratified. For doubtful items, consult a scholar you trust. Halalyzer never invents a ruling and never uses AI for the verdict.
L-Cystine; derivative of L-cysteine. Source-dependent: human-hair source HARAM (strict), synthetic/duck-feather HALAL — conservatively doubtful (mirrors the dictionary's `l-cysteine`).
Check it yourself with Halalyzer — free. Scan any barcode and get this same cited, AI-free verdict in seconds. The core verdict is always free.
Verdict is a deterministic computation from the cited standards above (zero AI/LLM in the verdict path). Product facts via Open Food Facts (ODbL). Authorities are linked, never mirrored. · Browse all · Transparency