l-proline
other nitrogen compoundFound in 579 ingredients across the CompKitchen flavor graph.
Look up another compound — search by name, CAS number, PubChem CID, or FEMA #.
- Formula
- C5H9NO2
- Molecular weight
- 115.13 g/mol
- PubChem CID
- 145742 — full record on PubChem
Properties
- Odor description
- odorless
- Odor threshold — in a food matrix
- 0.110 ppb – 21.6 ppb median 3.3 ppb · 7 published values · see all 7 with sources
- Volatility
- low
- CAS number
- 147-85-3
- Retention index
- 554
FEMA GRAS — Generally Recognized As Safe for flavoring use
- FEMA number
- 3319
- GRAS publication
- GRAS 5
- FEMA primary name
- L-Proline
Use-level matrix not extracted for this substance — check the source publication for current ppm guidance.
Published thresholds
7 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
0.110 ppb – 21.6 ppbMeasured in a real food, where the matrix shifts detection — not a clean-water value.
| Threshold | Matrix | Source | Paper |
|---|---|---|---|
| 0.010 ppb | water (food: onion) | Literature corpus | 35424663, 35558794, 38715825 +1 |
| Flagged: 334× from the median of this group. Excluded from the range above pending re-check against the source publication — shown rather than hidden. | |||
| 0.110 ppb | water (food: tea) | Literature corpus | 35424663, 35558794, 38715825 +1 |
| 0.230 ppb | water (food: rice) | Literature corpus | 35424663, 35558794, 38715825 +1 |
| 3.3 ppb | water (food: fish) | Literature corpus | 35424663, 35558794, 38715825 +1 |
| 4.7 ppb | water (food: unknown) | Literature corpus | 35424663, 38715825, 41703130 |
| 17.3 ppb | water (food: mushroom) | Literature corpus | 35424663, 35558794, 38715825 +1 |
| 21.6 ppb | water (food: garlic) | Literature corpus | 35558794 |
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.
Where you'd actually smell it
Odor Activity Value = measured concentration ÷ odor threshold (3.34 ppb, the engine's canonical value — see the 7 published values). OAV ≥ 1 = perceptible.
| Food | Concentration (ppb) | OAV | Source |
|---|---|---|---|
| rice | 622.8 | 186 ⚡ | — |
| onion | 300.0 | 89.8 ⚡ | — |
| garlic | 37.6 | 11.2 ⚡ | — |
| mushroom | 7.8 | 2.34 | — |
| fish | 3.4 | 1.03 | — |
| tea | 0.2 | 0.06 | — |
Concentrations from PubMed Central Open Access papers (free literature corpus, MIT-style licensed). Copper = OAV ≥ 10 (strongly perceptible). Green = OAV ≥ 1 (perceptible).
Found in
Measured impact first, then profile shareEvery ingredient known to contain l-proline. 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-proline in it. Full concentrations are in the OAV table above.
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