Compounds · Other compounds · Sulphur compounds
Dimethyl sulfide
Also known as DMS — an analysis may use any of these names
Boiled cabbage, sea, slightly fishy. At very low concentration it gives the sweet note of boiled corn.
- CAS
- 75-18-3
- Formula
- C2H6S
- Molar mass
- 62.13
- Odour threshold
- 0.300 ppbin water
- Boiling point
- ≈ 37 °C at atmospheric pressure
This compound boils at 37 °C, so it is lighter than any ordinary essential-oil component. It lies outside the 150–290 °C band, so the marker stops at the left edge — not because that is where it sits, but because the axis does not reach that far.
The two axes are 42 points apart. Volatility tells you whether the compound leaves a surface early or late; the threshold tells you how much of it the nose needs before it notices. When the two sit this far apart, they explain things the percentages on an analysis cannot explain on their own.
Where it comes from
Biosynthetic pathway: Sulphur compounds — enzymes cut sulphur precursors the moment tissue is damaged.
Dimethyl sulphide takes several routes. In boiled corn and cabbage it forms when heat breaks down an amino-acid precursor of the plant itself. In pond sludge and seawater it is a product of bacteria. One molecule, two completely different origins.
About the threshold figure
Low. Present in boiled corn, heated milk and many cooked vegetables.
Published thresholds differ by several orders of magnitude, because of differences in measuring method, sample purity and panel. The figure here is an order of magnitude for relative comparison, not a measurement. We give it only for compounds where the literature broadly agrees — 52 of the 106 compounds in the library. The rest are left blank rather than guessed.
Why it sits where it does
A molecule of only two carbons and one sulphur atom, boiling at 37 degrees, so under ordinary conditions it exists almost entirely as a gas.
Where else you meet it
Oxygen-starved pond sludge, the sea, boiled corn, beer, and beetroot.