10 Foods That Can Be Biofuels

When Doc Brown used the contents of Marty McFly's garbage to fuel up the DeLorean, it represented a brighter, happier future where we had found a way to shift from "evil" fuel — plutonium — to "good," organic fuel. It was an idealistic dream from 1989, when Back to the Future Part II came out, but now that we are only four years away from the time in the future that the three of them travel to in the sequel, we don't seem to be that much closer to using potato peels and coffee grinds to start our engines. Or are we?

As the disaster in Japan confirms fears about nuclear power, and both political conflicts and environmental disasters underscore the problematic reliance on fossil fuels, there's no time like the present to put food waste and byproducts to better use. However, the logistics of growing crops for fuel are being debated. The cultivation and manufacturing of food fuels do not seem much better for the environment, and the demand is driving food prices up worldwide, as the New York Times reports.

Which is why scientists are taking a closer look at various foods' natural characteristics to develop energy sources with less harmful impact. And there are plenty of brains behind the effort. For instance in a YouTube video, UCLA Professor of Engineering Bruce Dunn, like a less burnt-out Doc Brown, demonstrates his team's research using regular table sugar to power a small battery cell and maybe someday a car.

Like wind energy, it harnesses a completely natural process — the breakdown of enzymes in sugar. And whaddya know, many of our favorite and most widely cultivated foods contain the sugar needed this process, like apples and sugar beets. Sugar isn't the only food vice becoming virtuous. Known as a frat party punch-spiker, grain alcohol is actually the same thing as ethanol, and while we are already using corn and other crops to make it, even dairy by-products have also been turned into fuel-grade alcohol.

Although it sounds like a nerdy sixth-grader's science project, scientists at the Hebrew University of Jerusalem are actually using potatoes to power batteries. Though it's doubtful that we're going to take potatoes from the mouths of babes to run our iPods, understanding the "hidden powers" of something as universally available as a potato will be key in developing biofuels. Similarly, scientists are looking at the unique characteristics of edibles like mushrooms and pokeberries to identify processes that can lead to green sources of energy.

Elsewhere the "waste not, want not" ethos seems to have led researchers to ways of converting food waste into energy. Last year, a lab at the University of Missouri tested oil from coffee grounds on diesel engines, and University of Nevada Professor Mano Misra's team is creating fuel from chicken meal made from the feathers, blood, and guts, thereby prompting yet another 'why did the chicken cross the road' joke. Because it was in your gas tank.

Click for the 10 Foods That Can Be Biofuels Slideshow.

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