It's bad enough for some propeller airplanes to be referred to as being powered by rubber bands. Now the cynics could start having a dig at industrial aircraft flying on everything from cooking oil to melted algae.

With the civil aviation industry under increasing pressure from rising oil rates and environmental legislation, the race is on to find feasible options to conventional and these up until now appear to come down to different types of biofuel.

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

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

In 2007 Goldman Sachs mentioned Jatropha curcas as one of the finest prospects for future biodiesel production. It is resistant to drought and insects, and produces seeds consisting of 27-40% oil.

Recently, US aerospace giant Boeing, Brazilian aeronautical major Embraer and the Sao Paulo state Research Support Foundation transferred to perform research and advancement into using biofuels to power jet airliners. It was reported that Brazilian airline companies Azul, Gol, TAM and Trip would serve as tactical specialists for the job.

The latest airline to start exploring with new fuels is the Alaska Air Group which has actually conducted internal US flights using a mix of 80 % petroleum based fuel and 20% biofuel made from cooking oil. This mix, it is declared, can cut hazardous emissions by 10%.

One actually motivating development has actually been the relocation far from biofuels which complete head on with food consumers thereby avoiding a rate spiral. Not so long back, a surge in use of biofuels in automobiles caused a spike in maize costs as US farmers diverted too much corn to fuel processing.

Hopefully in the future, airline companies and drivers will focus biofuel consumption on non-food sources such as jatropha curcas and algae. It would be a mixed true blessing certainly if some people wound up starving just to please somebody else's green qualifications.