It's bad enough for some prop planes to be explained as being powered by rubber bands. Now the cynics could begin having a dig at business airplane flying on whatever from cooking oil to liquefied algae.

With the civil aviation market under increasing pressure from rising oil prices and ecological legislation, the race is on to discover feasible alternatives to traditional kerosene and these up until now seem to boil down to different kinds of biofuel.

Not remarkably, the first trials of alternative fuel were initiated by British aviation pioneer, Sir Richard Branson, whose Virgin Atlantic began London to Amsterdam flights with minimal biofuel usage in 2008. This was quickly followed by Lufthansa and Air New Zealand who each used different blends of regular fuel and bio derivatives including some from made from jatropha which can grow in soil thought about too poor for growing mainstream foodstuffs.

Jatropha is a genus of roughly 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 very best prospects for future biodiesel production. It is resistant to dry spell and insects, and produces seeds including 27-40% oil.

Recently, US aerospace giant Boeing, Brazilian aeronautical significant Embraer and the Sao Paulo state Research Support Foundation transferred to carry out research and development into making 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 project.

The current airline to begin exploring with brand-new fuels is the Alaska Air Group which has performed internal US flights using a blend of 80 % petroleum based fuel and 20% biofuel made from cooking oil. This mixture, it is claimed, can cut harmful emissions by 10%.

One really motivating advancement has been the relocation away from biofuels which compete head on with food customers therefore preventing a price spiral. Not so long earlier, a surge in usage of biofuels in vehicles caused a spike in maize rates as US farmers diverted excessive 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 mixed blessing certainly if some people wound up starving simply to please somebody else's green qualifications.