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

With the civil aviation industry under increasing pressure from rising oil prices and ecological legislation, the race is on to discover practical options to conventional kerosene and these up until now seem to boil down to various kinds of biofuel.

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

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 cited Jatropha curcas as one of the finest candidates 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 moved to bring out research and advancement into making use of biofuels to power jet airliners. It was reported that Brazilian airline companies Azul, Gol, TAM and Trip would serve as tactical experts for the job.

The most recent airline to begin explore new fuels is the Alaska Air Group which has performed internal US flights utilizing a blend of 80 % petroleum based fuel and 20% biofuel made from cooking oil. This mixture, it is declared, can cut harmful emissions by 10%.

One really encouraging development has actually been the move far from biofuels which compete head on with food consumers consequently preventing a cost spiral. Not so long earlier, a rise in use of biofuels in automobiles caused a spike in maize rates as US farmers diverted too much 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 combined true blessing certainly if some individuals ended up starving simply to satisfy another person's green credentials.