US-based Alaska Airlines has tested two commercial flights partially powered by a biofuel, alcohol-to-jet fuel (ATJ), made from sustainable corn.

The ATJ biofuel has been created by Gevo, which is involved in the development of renewable technology, chemical products and next-generation biofuels.

One of the two Alaska Airlines flights powered by ATJ flew from Sea-Tac Airport, Seattle, US, to San Francisco International Airport.

The second flight was operated between Sea-Tac Airport and Ronald Reagan Washington National Airport, US.

"Advancing the use of alternative jet fuels is a key part of our emission reduction strategy."

During their flights, the aircraft used a mix of 20% corn-based fuel and 80% conventional jet fuel.

Alaska Airlines communications and external relations senior vice-president Joseph Sprague said: "Alaska is committed to doing its part to reduce its carbon emissions. Advancing the use of alternative jet fuels is a key part of our emission reduction strategy.

"Gevo’s jet fuel product is an important step forward, in that it has the potential to be scalable and cost-effective, without sacrificing performance."

The use of biofuel blend in the two flights is estimated to reduce greenhouse gas (GHG) emissions by around 50%.

The latest demonstration flights mark the first biofuel produced from a new feedstock to be certified and approved by ASTM International, the aviation industry’s fuel standards association, since 2011.

Gevo CEO Pat Gruber said: "Flying a commercial flight with our ATJ made from renewable resources has been a vision of ours for many years, and it has taken many years of work to get this far.

"We believe our technology has the potential to be the lowest cost, renewable carbon-based jet fuel, given the efficacy of our technology.

"We look forward to moving forward with Alaska, and others in the airline industry, to make renewable jet fuel widely successful as a product that substitutes for fossil fuels, and ultimately helps to reduce carbon emissions."

While producing the biofuel, the company uses a process that converts bio-based isobutanol into an alcohol-to-jet synthetic paraffinic kerosene (ATJ-SPK) fuel.

In November 2011, Alaska Airlines conducted 75 flights fuelled with a biofuel derived from used cooking oil.

Alaska Airlines is also partnering with Washington State University-led Northwest Advanced Renewables Alliance (NARA) to advance the production and use of alternative jet fuel made from forest residuals, the tree limbs and branches that remain after a forest harvest.

In the next few months, the airline will fly a demonstration flight using 1,000gal of Gevo’s ATJ being produced by the NARA team and its partners.