By Matt McGrath
BBC Environment reporter
The sugar found in fruit such as apples and oranges can be converted into a new type of low-carbon fuel for cars, US scientists have said.
Could this be the fuel of the future?
The fuel, made from fructose, contains far more energy than ethanol, the scientists write in the journal Nature.
Separately, a British report on biofuels says all types of waste products, including plastic bags, can be used to make biodiesel fuel.
Critics of biofuels made from food crops say they drive up prices.
In both the European Union and the United States, politicians have heartily embraced biofuels as a way of reducing emissions of carbon dioxide and dependency on imported oil.
Critics say that the current biofuels - both diesel made from palm oil and ethanol made from corn - encourage farmers to switch land to fuel production, driving up the price of food in the process.
Now scientists at the University of Wisconsin-Madison say that a simple sugar called fructose can be converted into a fuel that has many advantages over ethanol.
It is called dimethylfuran - it can store 40% more energy than ethanol, and does not evaporate as easily.
The scientists say that fructose can be obtained directly from fruits and plants or made from glucose - but more work needs to be done to assess the environmental impact of this new fuel.
In Britain, researchers say that the technology now exists to create diesel fuel not just from palm oil but from a range of materials including wood, weeds and even plastic bags.
This process is called biomass to liquid and experts say that within six years up to 30% of Britain's diesel requirements could be met from this source.
Jeremy Tomkinson of the UK's National Non-Food Crops Centre said this next generation of biofuels could meet many needs beyond powering cars.
"The impact on society we're hoping will be far wider than simply 'we can give you a fuel now with a tenfold reduction in its carbon footprint'.
"Imagine now if chemicals that we use in the chemical industry also came from the same feed stock; [and that] the aircraft we fly to New York in also run on this? There's the big potential," he said.
The biggest drawback to this process is cost. Setting up new production facilities is estimated to be 10 times higher than for current biofuel refineries.