Spirulina
Spirulina is a naturally-occuring algae, harvested as a traditional food from freshwater lakes in Chad. Women harvest the algae from the lake and subject it to sun-drying, before selling it at local markets. According to Wikipedia it is 'used to make a broth for meals'.
But recently, the health food market in the United States has discovered spirulina. It is said to have 'antioxidant properties' and the powder is compressed into supplement pills and sold at high prices. So where does Zimbabwe come into this? Well, in Southeastern Zimbabwe, efforts are currently underway to develop methods of cultivating spirulina in the laboratory for high yields that could one day result in the construction of a spirulina processing plant, bringing a new source of income to a country with fairly low import rates.
Jatropha
Jatropha is a plant indigenous to the Americas, but now found 'throughout the tropics' (1). It is not eaten by animals due to toxicity levels and therefore used as a 'living fence' against animal crop damage in some countries (1), but in Southeastern Zimbabwe it is being cultivated for oil production.
The oil that is produced from the Jatropha seed can be used for biofuel, and was originally celebrated as a novel and environmentally friendly solution to an impending global energy crisis, as Jatropha grows well even on unfertile, sandy soils. However, growth rates and seed production rates fell way below expectations, and Jatropha is no longer favoured for biofuel production (2).
Instead, in Southeastern Zimbabwe, the oil of the Jatropha seed is being used to make soap.
Is this viable? The sap of the tree is said to be a skin irritant, and the seeds contain high levels of toxic compounds, yet I was told that the soap has skin-softening properties... I was given a sample, so I'll give it a try. But given the propensity of small children for trying to eat soap (when ingesting just three of the Jatropha seeds can kill a human adult), I think its future as a product will depend heavily on what further research has to say about health and safety issues!
Fish guts
Now here's an even more unlikely source of ... soap.
Every year, thousands of metric tonnes of freshwater tilapia are harvested from the Kariba dam in Zimbabwe. These fish are gutted before they are sold on the market, and usually the innards are simply discarded. However, waste products are called waste products for a reason - they could be utilised in some way, it's just a case of figuring out how.
A quick internet search tells me fish guts are, like Jatropha above, a potential source of biofuel. This fish farm in Honduras is one really interesting example of this.
But in Zimbabwe, as with Jatropha seeds, people are trying out a new use for the oil produced from fish waste: Soap!
The best thing about this soap is that it smells like fish. Just like fish. Fortunately chemists have recently discovered a method of neutralising the smell, though it's yet to be patented, so it'll be a while before fish gut soap is on the market. The current product really does smell very, very fishy. Again, I was lucky enough to be given a sample of this very unusual soap. But I'm not sure I'll be trying it out... in fact the reason I haven't uploaded a photo is because the thought of unwrapping it from its layers of plastic to take said photo, and consequently releasing the smell at this time in the morning, makes me feel a bit sick..
Anyway, if there's one thing that I've learnt from all of this, it's that thinking up innovative ways of using 'waste' products can be profitable, disastrous or hilarious - but never boring. And it's probably always worth giving things a go. Which is why after finding out all sorts of things about mopane caterpillars, I reckon the next big thing might well be 'mopane tea'...any guesses as to how this can be made?