It's bad enough for some prop airplanes to be referred to as being powered by rubber bands. Now the skeptics might start having a dig at commercial airplane flying on everything from cooking oil to melted algae.

With the civil aviation under increasing pressure from rising oil prices and ecological legislation, the race is on to find viable options to conventional kerosene and these up until now seem to come down to different types of biofuel.

Not surprisingly, the first trials of alternative fuel were started by British aviation pioneer, Sir Richard Branson, whose Virgin Atlantic began London to Amsterdam flights with limited biofuel usage in 2008. This was quickly followed by Lufthansa and Air New Zealand who each utilized different blends of routine fuel and bio derivatives including some from made from jatropha curcas which can grow in soil considered too bad for growing mainstream foods.

jatropha curcas is a genus of around 175 succulent plants, shrubs and trees (some are deciduous, like Jatropha curcas), from the family Euphorbiaceae.

In 2007 Goldman Sachs cited Jatropha curcas as one of the finest candidates for future biodiesel production. It is resistant to dry spell and bugs, and produces seeds containing 27-40% oil.

Recently, US aerospace giant Boeing, Brazilian aeronautical significant Embraer and the Sao Paulo state Research Support Foundation relocated to perform research and advancement into the use of biofuels to power jet airliners. It was reported that Brazilian airlines Azul, Gol, TAM and Trip would serve as strategic consultants for the job.

The current airline company to start experimenting with brand-new fuels is the Alaska Air Group which has carried out internal US flights utilizing a mix of 80 % petroleum based fuel and 20% biofuel made from cooking oil. This mixture, it is declared, can cut hazardous emissions by 10%.

One truly encouraging development has been the relocation far from biofuels which compete head on with food consumers thereby avoiding a price spiral. Not so long back, a surge in usage of biofuels in vehicles caused a spike in maize prices as US farmers diverted too much corn to fuel processing.

Hopefully in the future, airlines and vehicle drivers will focus biofuel consumption on non-food sources such as jatropha curcas and algae. It would be a blended blessing certainly if some people ended up starving just to satisfy somebody else's green qualifications.