Makrut lime leaf vs Curry leaf
The short answer
Two aromatic leaves from the same botanical family used in neighbouring cuisines, and routinely substituted by people who have neither. Both are Rutaceae, both are fried or infused whole, and there the resemblance ends. Makrut lime leaf is double-lobed, Southeast Asian, and sharply citric and floral — lime peel without any of the sourness. Curry leaf is a single small pointed leaflet, South Asian, and nutty, resinous and faintly smoky. Neither tastes like the other and neither belongs in the other's dishes: a Thai curry made with curry leaf is missing its citrus axis, and a South Indian tempering made with lime leaf tastes of the wrong continent. What they do share is a storage answer — both are worth having fresh or frozen and close to worthless dried.
Side by side
| Makrut lime leaf | Curry leaf | |
|---|---|---|
| Botanical identity | Citrus hystrix DC. | Murraya koenigii (L.) Spreng. |
| Part used | leaf, fruit | leaf |
| Origin | Tropical Southeast Asia — the Malay peninsula, Indonesia and Thailand — where the tree has been cultivated domestically for centuries. | The Indian subcontinent and Sri Lanka, where it grows wild and has been cultivated domestically for centuries. |
| Flavour notes | citric, floral, aromatic, faintly bitter | citric, resinous, nutty, faintly bitter |
| Heat | Not established | Not established |
| Flavour | Aromatic rather than tasted. Whole leaves perfume a broth and are not eaten; finely shredded, the leaf is eaten and contributes a bright citrus-floral note with a slight bitterness and a tough, fibrous texture if the shredding was not fine enough. | Mild in the mouth relative to how strongly it smells. The fried leaves are pleasant to eat, slightly bitter and nutty, and much of what the leaf contributes to a dish arrives as aroma rather than as taste. The dried leaf tastes of very little. |
| Aroma | Intensely citric — lime peel rather than lime juice — with a floral, faintly soapy edge and none of the sourness the smell suggests. Torn, it is one of the most immediately recognisable aromas in Southeast Asian cooking. | Citric and resinous with a distinctly nutty, faintly smoky edge, quite unlike any other leaf used this way. Bruising a fresh leaf releases it immediately; frying it in fat changes it, deepening the nuttiness and softening the citrus. |
Which should you buy?
Makrut lime leaf
The choice here is fresh or frozen against dried, and it is not close. Frozen makrut lime leaf keeps almost all of its aroma for a year and goes from the freezer straight into a pot; dried leaf has lost most of the citronellal that makes it worth using and fades further within months. If the only option is dried, a curry with several other aromatics will survive it and a tom yum or a salad will not — and in those cases leaving it out and not pretending is often the better dish, since dried leaf adds a hay note the fresh leaf does not have.
Curry leaf
The starkest fresh-versus-dried gap in this dataset, and the one where the widely available form is the wrong one. Dried curry leaf is sold everywhere and is worth very little; fresh leaf is worth going out of the way for, and frozen leaf is nearly as good and keeps for months. If the choice is between a jar of dried leaf and leaving the ingredient out, leaving it out and not pretending is often the better dish — the recipe will be missing something either way, and dried leaf adds a hay note that the fresh leaf does not have.
Full detail on makrut lime leaf and curry leaf, including evidence grades and sources for every claim above.