Secret ingredient: Kaffir lime

PUNGENT: Kaffir lime leaves.
PUNGENT: Kaffir lime leaves.

The leaves bring an elusive, slightly floral flavour to Thai food and the juice is used in skincare. But do you know how to handle the bounty from the wickedly thorny kaffir lime tree?

Originating in tropical Asia, Kaffir lime - or to use its Thai name, makrut - is a wickedly thorny member of the citrus family. Both the leaves and pungent, knobbly fruit are key players in the cuisines of South East Asia, particularly Thailand, where they form the sensory backbone of so many curries, soups and spice pastes.

The word 'kaffir' is a highly offensive racial slur of colonial South African origins. It was originally directed at black Africans and later the Javanese slaves of the Cape Colonies. The popularity of the fruit among these slaves, and fact that it was picked while still green, is thought to have led to its common name. It's unfortunate that this name has stuck but if you must use the 'K' word, at least mispronounce it, e.g. 'kaff-eer', never 'kaff-uh'. Better by far to use the Thai name, anyway. It's entirely inoffensive and altogether more apt.


Makrut is best summed up as the elusive, slightly floral and resinous quality lurking beneath the surface of many famous Thai dishes. The distinctive two-lobed leaves are added to stocks and curries much like bay leaves in European cuisines, and the rind of the fruit is used widely in spice pastes and traditional medicines.

Makrut juice is sparse, sour, and rarely used in cooking, but is said to make a good hair tonic and facial cleanser. Both leaves and rind are assertively aromatic (surprisingly, more resinous than citric) with notes of damask rose and violets.

In the larger centres fresh makrut leaves can be found year-round in the produce aisles of most supermarkets. The fruit is available from larger weekend markets and some fruit shops during the winter/spring season. Both leaves and fruit freeze well.

Trees are available from most garden centres in the North Island and given a warm (frost-free) sunny spot will keep you well stocked with leaves and fruit for many years. They are seriously thorny trees, so take care where you plant them.

Sorry, no substitutions will do. It's real makrut, either frozen or fresh, or nothing at all. Avoid dried leaves and rind. They are but a pale imitation of the real thing.

For an authentic entree to Thai cuisine, try a recipe using makrut from one of David Thompson's extraordinary books (Thai Food and Thai Street Food). This celebrated Aussie restaurateur and revered food writer is like the Julia Child of the Happy Kingdom, and as such the man who brought makrut to the masses.

Or you could make Makrut Liqueur. There's nothing Thai or traditional about it, but I think it's a special wee tipple all the same. Vibe-wise it's a little bit Limoncello, a little bit Absinthe and a large measure fragrant bliss.

Pack a one litre preserving jar with fresh, slightly bruised makrut leaves. Pour over vodka (must be at least 35 per cent  alcohol). Seal the jar, give it a good shake and place in a dark cupboard for six months.
When the six months are up, the leaves will now be very pale and the liquid emerald green. Strain though cheesecloth and dispose of the spent leaves.
Make a strong sugar syrup by boiling 1/4 cup of water with one cup of sugar. Remove from the heat as soon as the sugar has dissolved. Leave to cool slightly.
Combine the syrup with the makrut-flavoured alcohol. Bottle, shake vigorously and leave to settle for about a day. Best served straight from the freezer in a shot glass. It's potent stuff but very easy to drink.

To slice makrut leaves for salads etc, tightly roll and cut on either side of the stem, which is tough and so best discarded.
Whole makrut leaves are leathery and largely inedible. Remove before serving.
Makrut fruit eventually ripen to a dull yellow but are best used when hard, shiny and green. The riper they are the lower the essential oil content and therefore flavour.

Virgil Evetts is a member of the New Zealand Guild of Food Writers. Follow his adventures in food, gardening and urban farming here.

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