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

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

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

Jatropha is a genus of approximately 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 bugs, and produces seeds including 27-40% oil.

Recently, US aerospace giant Boeing, Brazilian aeronautical major Embraer and the Sao Paulo state Research Support Foundation moved to carry out research and development into the 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 task.

The most recent airline company to start try out new fuels is the Alaska Air Group which has performed internal US flights utilizing a mix of 80 % petroleum based fuel and 20% biofuel made from cooking oil. This mix, it is claimed, can cut damaging emissions by 10%.

One really motivating development has been the move away from biofuels which contend head on with food customers therefore a price spiral. Not so long earlier, a rise in usage of biofuels in vehicles triggered a spike in maize prices as US farmers diverted excessive corn to fuel processing.

Hopefully in the future, airlines and vehicle drivers will focus biofuel intake on non-food sources such as jatropha curcas and algae. It would be a combined true blessing indeed if some individuals ended up starving just to please another person's green qualifications.