It's bad enough for some propeller airplanes to be described as being powered by elastic band. Now the skeptics might begin having a dig at industrial airplane flying on everything from cooking oil to melted algae.

With the civil air travel market under increasing pressure from increasing oil rates and legislation, the race is on to discover practical alternatives to traditional kerosene and these up until now appear to boil down to different kinds of biofuel.

Not remarkably, the first trials of alternative fuel were started by British air travel leader, Sir Richard Branson, whose Virgin Atlantic started London to Amsterdam flights with minimal biofuel use in 2008. This was quickly followed by Lufthansa and Air New Zealand who each utilized various 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 is a genus of approximately 175 succulent plants, shrubs and trees (some are deciduous, like Jatropha jatropha curcas), from the household Euphorbiaceae.

In 2007 Goldman Sachs cited Jatropha curcas as one of the best candidates 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 moved to bring out research and advancement into making use of biofuels to power jet airliners. It was reported that Brazilian airline companies Azul, Gol, TAM and Trip would serve as tactical specialists for the project.

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

One truly encouraging development has been the relocation far from biofuels which complete head on with food consumers thereby avoiding a cost spiral. Not so long ago, a surge in use of biofuels in automobiles caused a spike in maize prices as US farmers diverted excessive corn to fuel processing.

Hopefully in the future, airline companies and vehicle drivers will focus biofuel usage on non-food sources such as jatropha and algae. It would be a mixed blessing undoubtedly if some individuals wound up starving simply to satisfy another person's green qualifications.