By our count, about three-quarters of US biodiesel producers have annual capacities of 20 million gallons or less, comprising about a third of total industry capacity.

FORBES: The Rise and Imminent Fall of Biodiesel

Per capita consumption of soda in the US, for example, has declined from around 54 gallons per year in 1998 to 44 gallons today.

FORBES: The Doctor Orders Up More Overseas Growth For Dr Pepper

The commander of the US Coast Guard in the Galveston region, Capt Marcus Woodring, said about five gallons (19 litres) of tar balls from the Deepwater Horizon leak had been found on Saturday.

BBC: Gulf oil spill reaches Texas as tar balls wash ashore

This demand comes after US Geological Survey research suggested up to 40, 000 barrels (1.7 million gallons) of oil a day may have been escaping before the cap was put on - doubling earlier estimates.

BBC: BP criticism not about nationality, says Obama