It's bad enough for some prop planes to be described as being powered by elastic band. Now the cynics might start having a dig at commercial aircraft flying on everything from cooking oil to liquefied algae.

With the civil air travel industry under increasing pressure from increasing oil costs and ecological legislation, the race is on to find practical alternatives to standard kerosene and these up until now appear to boil down to numerous types of biofuel.

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

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

In 2007 Goldman Sachs pointed out Jatropha curcas as one of the finest prospects for future biodiesel production. It is resistant to dry spell and pests, 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 perform research and advancement into making use of biofuels to power jet airliners. It was reported that Brazilian airlines Azul, Gol, TAM and Trip would function as strategic experts for the task.

The current airline company to start explore new fuels is the Alaska Air Group which has 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 harmful emissions by 10%.

One truly encouraging development has actually been the relocation away from biofuels which compete head on with food consumers thus avoiding a rate spiral. Not so long earlier, a surge in usage of biofuels in cars and trucks caused a spike in maize costs 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 combined blessing certainly if some individuals ended up starving simply to please somebody else's green credentials.