Monkey orange, an eagerly sought-after fruit

Monkey orange is the collective common name for the fruit of at least five different Strychnos tree species, which occur from Durban/South Africa up to Western Tigray in Ethiopia. These fruits are highly delicious, and all parts of the trees are used for various medicinal purposes.

Description of tree and fruit

The bark of the stems of these trees can be from smooth to heavily corky and longitudinally fissured, depending on the species. The leaves of all species however are characteristically 3-5 veined from the base and are shiny green on the upper- and dull green on the lower side.

Fruits turn yellow when ripe and there are always green and yellow fruits on the same tree. Only yellow fruits are eaten, which are still hanging on the tree. Fruits already fallen down to the ground are normally overripe and already start fermenting. Harvesting time is from September to December. And as at this period of time both maize as well as green vegetables are scarce, monkey oranges are a welcome source of nutrients.

Harvesting monkey orange fruits

Ripe, yellow fruits can be easily dislodged from the tree by tipping them with a stick. The fruit itself got a very hard shell. This shell can be cracked by blows with a stick always on the same circumferential line. It is highly discouraged to use a knife for cutting open the shell, as a blade can easily slip off.

Once I tried to cut open a Corky monkey orange with a knife – as I wanted to use the dried shell as a water container – but will probably never do it again. The danger of slipping off the hard shell is too high.

Inside the shell, there is a cluster of tightly packed seeds, which are surrounded by a brownish, jelly-like fruit layer, sticking tightly to the seeds. Locals are taking a wooden twig, dislodge within the open shell single seeds and suck on these single, jelly-covered seeds. The outermost jelly-layer is swallowed and the slightly fibrous layer around the seed sucked out. Thereafter they spit out the remains with the seed in center. Reason for explaining this procedure in such detail is, that the seeds are poisonous. They contain strychnine, and when swallowing them a purgative reflex will at least follow.

Benefits of monkey oranges

Reasons why monkey oranges are so sought after are threefold.

1 – They taste exceedingly complex and well

2 – They are highly nutritious

3 – Many parts of the trees are used medicinally

Taste of monkey orange depends a lot on the degree of ripeness. If ideally ripe, different people describe the taste differently. In our group, the different participants described the taste as follows:

St.W.: Mix of water melon and maracuja

S.W.: Bubble gum, followed by maracuja and water melon

B.H.: Overripe banana and sour drops, followed by a mix of citrus fruits

K.H.: Overripe banana, maracuja & watermelon, followed by a splash of lime

Basically, the taste of an ideally ripe monkey orange is something like an original Thai dish: A journey in the mouth from one taste to another taste to another one.

Picture on the right side above shows a Corky monkey orange (Strychnos cocculoides), which is already on the verge of being overripe. The fruit meat is not dark brown and shiny any more, but is turning to a khaki color. The taste and smell of such an overripe monkey orange does not contain sour notes any more but overwhelmingly smells more like an overripe banana.

The flesh of the seeds is not only eaten raw but will also be sun-dried as a fruit preserve. Before eating, the seeds than will be removed and discarded.

Nutritional value of monkey oranges

The nutritional value of one species of monkey oranges, the Spiny monkey orange (Strychnos spinosa) was determined  and is described in the article at this link.

Strychnos spinosa got an:

  • Energy value of 1923 KJ/100 g (abt. 460 kcal/100 g)
  • Total soluble sugar: 16-22%
  • Carbohydrate: 42-60%
  • Fat: 2-31%
  • Crude protein: 11-22%
  • Vitamin C: 20-88 mg/100 g
  • High value of Potassium
  • Plus is proven to act antioxidant, antimicrobial, anti-inflammatory, anti-tick (!) and anti-malaria.

Exact values can be obtained from the Graphical Abstract of the recommended article in above link.

Medical value of bark, leaves, roots, and fruit seeds is high, but as I’m not a medical doctor, I do not want to comment on that.

In many African countries it is widely believed that the presence of strychnine in the bark and unripe fruit along with other alkaloids are responsible for helping overcome the venom of certain snakes, such as Mamba. According to the foremost snake bite expert from South Africa, Johan Marais, this is ‘not true at all’. See this link.

Lessons learned about Monkey oranges:

  • Monkey oranges are available at a time of the year when other fruits and vegetables are scarce
  • They taste exceedingly complex and well
  • Opening the hard shell is best done with a stick and circumferential blows
  • Energy value is 1923 KJ or 460 kcal/100 g, which is very high
  • Also, very high Vitamin C, potassium and biological activities