Finger limes are becoming “a thing” now, but not many people know much about them. Read this to surprise your friends and family with an in-depth understanding of Australia’s own Bush Caviar!
Unopened finger limes are roughly the size (3-12cm long) and shape of… you guessed it, human fingers. At first glance, you probably would not associate this fruit with oranges and lemons, but it is a bona fide native citrus (Citrus Australasica). The citrusy skin, coloured in green, brown, and red shades gives the game away.
So, externally quite dull. But the fun starts when you break a ripe one open. Small, colourful, shiny, juice-filled, caviar-like blobs ooze out. These globular blobs are the finger lime’s juice vesicles, and like pomelo vesicles they don’t pop without a fight. To understand the growing appeal of finger lime, you must see these fascinating jewel-like vesicles up close.
Where does Finger Lime Come From?
People have been eating finger limes in Australia for thousands of years, from the very beginning of people in Australia. The trees grow wild in native coastal bushland on the border of NSW and Queensland. Being a significantly sized tree (they grow up to 8 metres tall), many were cleared and forgotten by early settlers. Back then, few people were concerned about how pretty the “caviar” would look on flambeed oysters. Besides, there were other, juicier, more useful, bush citruses like the Desert Lime readily available.
Like so many of the hundreds of other half-remembered native Bush Tucker plants, finger limes languished untasted in protected areas for decades. Then, beginning in the 1980s, the Australian Native Plants Society (Australia) (ANPSA), that veritable populariser of native flora, began talking about them. Their legendary Study Groups, peopled by enthusiastic amateur botanists, spread the word until it reached the ears of sensation-hungry gourmet chefs in the 1990s. Finger limes were a hit in the “fancy restaurant dinner” market and now they are breaking into the mass market.
Finger lime cultivation is a hot export-led growth opportunity, with some growers having planted orchards with thousands of trees.
What use are Finger Limes?
Finger limes are best used for their visual effect in garnishes. Unlike a “regular” lime, slicing a cross-section will yield little flavour, and squeezing will give you a bunch of intact vesicles and little juice. For best results, add the juice vesicles to desserts and salad to generate an interesting sour pop mouth experience. You can place a dollop of the “caviar” on shellfish and white fish fillets for the eye-candy effect, but also squeeze some “regular” lime juice over it if you want the flavour to penetrate.
Finger limes are also used to impart “fanciness” to expensive marmalades and other products which would otherwise use regular lime flavours.
Finger Lime Nutrition
There are no nutrition surprises when it comes to finger limes – they pretty much follow the pattern of other limes. Apart from significant levels of Vitamin C (30mg/100g) and a wide array of phytochemicals (polyphenols and terpenes), they are low in nutrients. 100g of finger limes have 10g carbs, 30 calories (126kJ), and 2.8g dietary fibre.
Types of Finger Limes
As is the way with other unusual food which gets “buzz”, there is much misinformation as to the types and claimed benefits of finger limes. There are more than 40 different cultivars (varieties) of finger lime available, and each variety may have a hundred different shades of colour. The colour of citrus flesh is determined by a family of chemicals called cyanins. Different types of cyanins make different colours, and different growing and ripening conditions determine the cyanins. Depending on the temperature, water, and soil chemistry, it is possible to get different coloured finger limes picked from the same tree at different times.
That said, the top three types of finger lime cultivars are:
- Pink Ice, which has pink juice vesicles and brown rind
- Crimson Tide, with red juice vesicles and brown rind
- Chartreuse, a green-skinned fruit with yellow juice vesicles
In general, there is not much point in worrying about which type of finger lime is best – nutritionally they are much of a muchness. The flavour of finger lime is more determined by growing conditions than colour (the colours taste the same).
In addition to the regular cultivars, agriculturists are experimenting with hybrids of finger lime and other citrus fruits. An example is the finger lime/mandarin hybrid fruit developed by the CSIRO.
Where can YOU get them?
Finger limes have not yet made it to the produce section of bug supermarkets. However, they can be found online from distributors and at local farmers markets. Bear in mind that online, all-year-round stores are possibly selling defrosted fruit which has likely lost its snap. Fresh ripe finger limes are broken with a snap and ooze vesicles, kind of like fresh green beans. Old and thawed finger limes bend without breaking, and their juice vesicles must be carefully scooped out after cutting.
Keeping Finger Limes
If you are keen to experience finger limes, then you will probably want to plant your own tree. Freshly picked finger limes spoil fast (unless they have been chemically “enhanced”) and it is a rare week-old finger lime that has not developed patches of mould. This rapid spoilage, and the export market demand, is the main reason that finger limes are so expensive.
It is not especially difficult to grow and nurture a finger lime tree like these from your local Bunnings. The tree develops excellent citrus blossoms in late summer and fruit in winter or early spring.