Lemon aspen

What it is

The fruit measures about 2 cm (¾ in) across. Cut through it and the core holds small dark seeds, each enclosed in a husk. The juice has a strong lemon-like acidity, a grapefruit note and a citrus scent. Acronychia acidula is the plant usually called true lemon aspen, a member of the Rutaceae, the citrus family.

Where it comes from

Lemon aspen comes from tropical north Queensland, including the Atherton Tablelands. Its wild home includes upland and mountain rainforest. It is also grown farther south, in the hinterland of northern New South Wales, where it fruits in edible gardens such as Forage Byron Bay's. It also grows in Hawaiʻi, including plantings around Kona on Hawaiʻi Island.

How it's eaten where it grows

In Australia, chef Mark Olive turns lemon aspen juice into curd tartlets. He whisks the juice with egg, sugar and grated lemon zest over simmering water, then adds butter until the curd thickens. Once chilled, it fills small sweet pastry cases and gets a dusting of lemon myrtle.

The fruit also works on the savoury side, in sauces and dressings. Whole frozen fruit gives cooks the flesh to work with; juice, sweetened syrup and powder are other preparations used in the kitchen.

How it's grown

Lemon aspen favours tropical or subtropical rainforest conditions, with plenty of rain and soil that drains well. At Forage Byron Bay in The Pocket, northern New South Wales, a tree produced fruit after five years. The fruit is picked by hand and must be cold-processed within 12 to 24 hours of harvest.

When and where you'll find it

At Forage Byron Bay, lemon aspen usually fruits between January and mid-April, and the season there can last only four to eight weeks. Frozen fruit carries the flavour beyond that local season: Naturally Native lists snap-frozen fruit grown in northern New South Wales. Australian native-food specialists also offer juice, sweetened syrup and powder. The syrup already contains added sweetness, while the frozen product is whole fruit.