l-cysteine
other sulfur compoundFound in 398 ingredients across the CompKitchen flavor graph.
Look up another compound — search by name, CAS number, PubChem CID, or FEMA #.
- Formula
- C3H7NO2S
- Molecular weight
- 121.16 g/mol
- PubChem CID
- 5862 — full record on PubChem
Properties
- Odor description
- sulfury
- Odor threshold — in a food matrix
- 0.452 ppb – 1.8 ppb median 0.670 ppb · 3 published values · see all 3 with sources
- Volatility
- low
- CAS number
- 52-90-4
FEMA GRAS — Generally Recognized As Safe for flavoring use
- FEMA number
- 3263
- GRAS publication
- GRAS 5
- FEMA primary name
- L-Cysteine
Use-level matrix not extracted for this substance — check the source publication for current ppm guidance.
Published thresholds
3 measured values from the literature. Grouped by what was actually measured — a threshold smelled in clean water, tasted in the mouth, or measured in a real food are three different quantities and are not pooled.
In a food matrix
0.452 ppb – 1.8 ppbMeasured in a real food, where the matrix shifts detection — not a clean-water value.
| Threshold | Matrix | Source | Paper |
|---|---|---|---|
| 0.452 ppb | water (food: lime) | Literature corpus | — |
| 0.670 ppb | water (food: fish) | Literature corpus | — |
| 1.8 ppb | water (food: unknown) | Literature corpus | — |
Only values we can attribute are listed. Where a compendium's licence does not permit public attribution its figures are omitted here, so every number on this page traces to a citable source.
Found in
Measured impact first, then profile shareEvery ingredient known to contain l-cysteine. Ingredients with a measured concentration come first, ranked by odour activity; the rest follow by how large a share of that ingredient's profile this molecule is. The figure beside each is how many different compounds that ingredient has in total — not the concentration of l-cysteine in it.
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