Travelers can now fly on trans-Atlantic commercial flights on a jumbo jet fueled in part by the same oil that was used to cook French fries and catfish.

“The first question when we landed was, ‘Was it smelly?’ No, it wasn’t smelly,” said Jos Nijhuis, the president of the Schiphol Group — a Dutch firm investing in the airline KLM’s biofuel flight schedule — to the press last Thursday, when the airline completed the first of 25 round trips between New York and Amsterdam partially powered by cooking oil.

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Dutch airline KLM is no stranger to experimenting with biofuels. It has been using them on passenger flights in Europe since September 2011. However this is the first time the fuels – which are said to reduce carbon emissions by up to 80% — will be used on a regular trans-Atlantic flight schedule.

According to the Air Transport Action Group, a global not-for-profit that represents the airline industry, if commercial aviation were to source even just 6% of its fuel supply by 2020 from biofuel, it would reduce its overall carbon footprint by 5%. The mix KLM is currently using on its flights is 25% biofuel compared to 75% jet fuel.

“It’s indistinguishable on a molecular level” from the usual jet fuel, said Captain Rick Shouten to the press at the launch on Thursday. The biofuel came from waste cooking oil from Louisiana restaurants. Used to cook Cajun dishes such as catfish and cracklins, the leftover oil was refined and then trucked to JFK Aiport to help power the engines.

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Though biofuels are regarded by the aviation industry as one of the best options in reducing its carbon footprint, it does have its problems. The fuel is expensive compared to normal kerosene jet fuel, costing roughly three times the price of the latter. The issue of using sustainable biofuels that do not have a negative impact on food crops and prices as well as land use is also a concern.

The airline is hoping that as the use of biofuels, including sustainable biofuels, becomes more widespread, the price will drop. Hopefully the only problem the airline will have to deal with next is convincing passengers that their plane won’t smell like fries.

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