The short version: green lentils are sold with the seed coat on, red lentils are sold with it off. Everything else follows from that.
Seed coat and cotyledon
A lentil consists of a seed coat surrounding two cotyledons. The coat carries the pigment that gives green, brown, black and speckled lentils their exterior colour. The cotyledons underneath are usually orange to salmon. Remove the coat by dehulling and you expose that inner colour — which is what the market calls a red lentil.
This means “red lentil” is primarily a processing description. The varieties grown for the red trade are selected for a deep orange cotyledon, thin coat and easy hull release, but the red appearance is created in the mill, not in the field.
Whole and split
Once the coat is off, the two cotyledons separate easily. Red lentils are therefore most often traded split, produced by pulse splitting. Whole dehulled red lentils exist and command a premium because holding the cotyledons together through dehulling requires careful conditioning. Green lentils are almost always traded whole, since the intact coat is the point.
Cooking behaviour
| Attribute | Red (dehulled, usually split) | Green (coat on, whole) |
|---|---|---|
| Cook time | Short | Substantially longer |
| Shape retention | Breaks down, purées | Holds shape |
| Soaking | Not required | Optional, shortens cooking |
| Typical texture | Smooth, thick | Firm, distinct grains |
The coat is the barrier to water ingress and the structure that holds the seed together. Without it, red lentils hydrate fast and collapse into a purée — ideal for dal, soups, purées and thickening, useless for a salad. Green lentils hold their form through a long simmer, which is why they dominate salads, side dishes and ready meals where visible whole lentils are part of the presentation.
Quality parameters that differ
Red lentil specifications centre on colour uniformity of the cotyledon, split ratio, unhulled seed content and powder or fines generated by the mill. Green lentil specifications centre on seed coat integrity, calibration, absence of chipped or split seed, and coat colour consistency. A green lentil with a broken coat is a defect; a red lentil with a coat still attached is a defect.
Markets
Red lentils move mainly into South Asian, Middle Eastern and North African consumption and into European industrial soup and ready-meal manufacture. Green lentils move into European and North American retail, food service and canning. Ukrainian growers supply both, with green and brown types easier to place from a standing crop because they require less specialised milling. See red lentils and green lentils, and split versus whole lentils for the commercial trade-off between the two forms.