It's bad enough for some propeller planes to be referred to as being powered by rubber bands. Now the skeptics could begin having a dig at industrial airplane flying on whatever from cooking oil to melted algae.

With the civil air travel market under increasing pressure from rising oil prices and ecological legislation, the race is on to find feasible options to traditional kerosene and these up until now appear to boil down to numerous kinds of biofuel.

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

jatropha curcas 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 pointed out Jatropha curcas as one of the best prospects for future biodiesel production. It is resistant to dry spell 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 airlines Azul, Gol, TAM and Trip would act as tactical consultants for the job.

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

One actually encouraging development has been the move away from biofuels which contend head on with food customers therefore avoiding a cost spiral. Not so long ago, 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 drivers will focus biofuel consumption on non-food sources such as jatropha curcas and algae. It would be a mixed true blessing certainly if some individuals wound up starving just to satisfy someone else's green qualifications.