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

With the civil air travel industry under increasing pressure from rising oil rates and ecological legislation, the race is on to find practical alternatives to conventional kerosene and these so far appear to come down to various types of biofuel.

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

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

In 2007 Goldman Sachs mentioned Jatropha jatropha curcas as one of the very best candidates for future biodiesel production. It is resistant to dry spell and insects, and produces seeds consisting of 27-40% oil.

Recently, US aerospace giant Boeing, Brazilian aerial major Embraer and the Sao Paulo state Research Support Foundation transferred to bring out research study and development into the usage of biofuels to power jet airliners. It was reported that Brazilian airline companies Azul, Gol, TAM and Trip would act as strategic experts for the job.

The latest airline company to begin try out new fuels is the Alaska Air Group which has conducted 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 hazardous emissions by 10%.

One truly encouraging development has been the move far from biofuels which contend head on with food customers thereby avoiding a rate spiral. Not so long earlier, a surge in usage of biofuels in vehicles caused a spike in maize costs as US diverted too much corn to fuel processing.

Hopefully in the future, airlines and drivers will focus biofuel intake on non-food sources such as jatropha and algae. It would be a combined true blessing certainly if some individuals wound up starving just to please somebody else's green credentials.