Curry leaf

• kadi pattaकढ़ी पत्ता

  Hindi

  Literally the leaf for kadhi, a yoghurt-based dish. It does not mean "the leaf that goes in curry powder", which it does not.

• karuveppilaiகருவேப்பிலை

  Tamil — Tamil Nadu

• karivepakuకరివేపాకు

  Telugu

• karibevuಕರಿಬೇವು

  Kannada

• kariveppilaകറിവേപ്പില

  Malayalam

• kadhilimb

  Marathi

  Also called "sweet neem" across several Indian languages, which is misleading in English: it is not neem, and neem leaf is bitter and not a culinary substitute.

• karapinchaකරපිංචා

  Sinhala — Sri Lanka

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.

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.

Deep glossy green fresh, turning matt olive and then brownish on drying. Colour is the most reliable visible sign of how much aroma a batch has left.

Thin and pliable fresh, crisping to a brittle chip within seconds in hot fat. Dried leaves are brittle from the start and stay leathery when rehydrated.

• Sabinene — A large share of the fresh, resinous top note.
• Caryophyllene — Warm and faintly peppery, sitting underneath the citrus.
• Pinene and limonene — The citrus-family character that places the smell correctly once you know the plant is a Rutaceae.

Hot fat, a few seconds, and eat the leaves. Curry leaf gives its aroma to oil or ghee far better than to water, so the standard use is a tempering: heat the fat, add mustard seed and let it pop, then the curry leaves, which crackle and crisp almost immediately, then asafoetida and dried chilli, and pour the lot over the dish or start the dish in it. They spit if wet, so pat them dry. Do not fish them out at the end — unlike bay leaves they are meant to be eaten, and the crisped leaf is one of the good things about the dish. Use them fresh, use twice as many as you think, and if you only have dried, use several times as many and expect less.

South Indian and Sri Lankan cooking above all, and structurally rather than as a garnish: in the tempering for sambar, rasam, dal, poriyal and avial, in lemon rice, in coconut chutney, and in curry-leaf chutney where it is the main ingredient. It appears across western India in Gujarati and Maharashtrian kadhi, and in Malaysian and Singaporean dishes carried by South Indian communities. It works with lentils, coconut, potato, aubergine, okra, prawns, fish and yoghurt, and alongside mustard seed, asafoetida, dried chilli, turmeric and fenugreek — the standard tempering company.

• frying — The defining preparation. Dropped into hot oil or ghee the leaves crackle and crisp within a few seconds, and the aroma compounds move into the fat, which then carries them through the whole dish. This is why the tempering happens at the start or is poured over at the end rather than the leaves being stirred in.
• boiling — Much less effective. Simmered in a watery curry the leaves give up a fraction of what they give to hot fat, and long boiling leaves them limp and largely spent.
• grinding — Fresh leaves pound into chutneys and wet masalas readily and keep their citrus character raw, which is a distinct use from the fried one and gives a sharper, greener result.

Bruise a leaf between finger and thumb and smell it. A good fresh leaf gives an immediate citric and resinous hit; a tired one smells green and generic. For dried leaves, crumble one — if there is no smell in your palm, there is none in the pan either.

• Blackened or slimy leaves, which means the bag held condensation.
• Curled, brittle leaves that have dried out in the refrigerator rather than being dried deliberately.
• Yellowing, which is the first sign on a fresh sprig and precedes aroma loss.
• Dried leaves faded from olive to pale brown.

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.

• Deep glossy green, still attached to the stem, with no yellowing or blackening.
• A strong citric-resinous smell when a leaf is bruised — the only test that matters, and it can be done in the shop.
• Sold as fresh produce rather than from the spice shelf, which is where the good leaf is.
• Frozen whole leaf in preference to dried, where fresh is not available.
• Buy the large bunch and freeze most of it rather than buying a small jar of dried.

No grading standard exists at consumer level, and none of the usual spice-trade specifications apply because this is sold as fresh produce. Freshness and how recently the sprig was cut are the only quality variables, and neither is ever stated.

Rutaceae

A small tree or large shrub to about four metres, bearing pinnate leaves of eleven to twenty-one small pointed leaflets, white flowers and small black berries. It is grown domestically across South Asia and widely as a pot plant elsewhere by households who cannot buy the leaves fresh.

The Indian subcontinent and Sri Lanka, where it grows wild and has been cultivated domestically for centuries.

• IN (Tamil Nadu, Kerala, Karnataka, Andhra Pradesh) — origin. The southern states, where it is most heavily used and most widely grown.
• LK — major producer
• MY — notable producer. Grown for the South Indian diaspora communities.
• AU — notable producer. Commercial growing for export of fresh leaf.

Sprigs cut by hand as needed, year-round in the growing regions. For export the leaf is packed fresh on the stem and air-freighted, which is why fresh curry leaf is expensive outside South Asia and why its quality varies so much on arrival.

1. Cutting and sorting — Sprigs cut and sorted, leaves left on the stem for the fresh trade because they keep better attached.Why: The fresh leaf is the product; everything below is a fallback.
2. Drying — Shade-dried or air-dried for the dried trade. This is where most of the aroma is lost: the essential oil is dominated by volatile terpenes and very little survives.Why: Shelf stability, at a very high cost to the aroma.
3. Freezing — Whole leaves frozen on or off the stem, increasingly the export form of choice.Why: Preserving far more of the aroma than drying does, and the reason frozen leaf is worth buying where fresh is unavailable.

No consumer grading standard. The fresh leaf is judged on the plate rather than by specification: deep green, glossy, still attached to the stem, and unmistakably aromatic when a leaf is bruised between the fingers.

Mostly a garden and smallholding crop rather than a plantation one. Grown from seed or suckers, cut repeatedly through the year, and harvested as whole sprigs. Very little of the world crop passes through a formal supply chain, which is part of why almost none of it is graded.

Tropical and subtropical. It tolerates drought reasonably and frost not at all, which is why it is a windowsill pot plant rather than a garden shrub in temperate countries.

Documented in South Indian and Sri Lankan cooking over a very long period as a domestic rather than a traded plant, growing in gardens and yards and picked as needed. It never became a spice-trade commodity, for the same reason it is still difficult to buy fresh outside its range: the leaf is worth having fresh and worth very little dried, and nothing worth very little dried travelled far before air freight. Its spread beyond South Asia has followed the South Indian and Sri Lankan diaspora rather than any commercial trade.

A modern trade only, and a fresh-produce one rather than a spice one: air-freighted sprigs and, increasingly, frozen leaf. The dried leaf has a much older commercial presence and a much poorer reputation, deservedly.

Long recorded in Ayurvedic and South Asian household tradition, including as a digestive. Held here as tradition and as cultural context, and not as a health claim.