It’s not the OPEC you’re thinking of. This OPEC is the Orange Peel Exploitation Company and it’s composed of an international team of researchers who are looking for innovative new ways to use orange peels.
It might sound like an odd venture, but the reality is that global agriculture produces some 15.6 million tons of orange and other citrus waste per year. That’s a lot of orange peels!
Citrus is an industry where almost half of the harvested product goes to waste in the form of peelings. Traditionally the peels have been burned or sent to landfill. Some large-scale juice manufacturers are able to process the peels as feed for livestock or pectin (a common food additive), but both of these processes involve additional expenses and energy.
The OPEC researchers include scientists from University of York, the University of Sao Paulo and the University of Cordoba. They envision a “zero waste” biorefinery in which high-intensity, low-temperature microwaves are used to separate the liquid from the cellulose in the orange peels. Several products, including bio-enthanol biofuel, are possible from this process.
British chemist James Clark, a professor at the Center for Green Chemistry at the University of York, presented the process at a recent British Science Festival and explained that “The orange peel has an interesting chemical composition that makes it very easy to convert into fuel.”[^1]
Despite the food vs. fuel debate, which argues that land and resources should not be taken from food agriculture in order to grow biofuel crops, and other issues surrounding some conventional biofuels, Clark defends his new biofuel because of its low cost and the fact that you don’t need a refinery like those used for oil. It’s also attractive because the orange peels are an existing food waste product so no new land would be needed to produce the peels.
Igor Polikarpov, professor at the Physics Institute of São Carlos, sees the orange peel biofuel as an interesting development. But, he says, “it is necessary to put in the equation a way to increase the added value with the available technologies. Limonene (the largest component in the oil found in orange peels), has a high added value. Using it as the raw material for the generation of biofuels will make the whole process much cheaper.”[^2]
At the University of Central Florida, in the heart of America’s orange-growing country, researcher Henry Danielli has also been looking into ways to turn orange peels, newspapers and other food waste into biofuels. His process uses a genetically derived tobacco enzyme to break down the “woody” non-food biomass and enabling a wide range of plant waste to replace corn as a feedstock for biofuel.
Whether it’s enzymes or microwaves, it seems that researchers are intent on finding a way to utilize the byproducts of the massive orange-growing industry. Who knows–in the near future, your morning glass of orange juice may be seen as the waste by-product of the latest and greatest new biofuel!
To learn more about the issues around food waste in America, see our previous post explaining food waste and what we can do about it…
[^2]: Same as above.