Frying food releases fatty acids into the air which help form cooling clouds, study shows

Fatty acids released into the air from cooking oil help form clouds, which cool the climate. NEW PAPER FILE PHOTO

LONDON - Frying might not be good for one's waistline, but it could be good for the planet, say scientists.

Fatty acids released into the air from cooking may help to cool the climate by encouraging cloud formation, say researchers from Britain's University of Reading.

They believe that the fatty molecules from frying arrange themselves into complex 3-D structures in atmospheric droplets, according to a BBC report on Thursday (Nov 23).

The team believes that the formation of these structures is likely to extend the atmospheric lifetimes of these molecules and that this affects how clouds form.

Dr Christian Pfrang, co-author of the study, said: "It is known that fatty acid molecules coating the surface of aerosol particles in the atmosphere may affect the aerosol's ability to seed cloud formation.

"However, this is the first time scientists have considered what these molecules do inside of the aerosol droplet, and we have shown that they may be assembling into a range of complex, ordered patterns and structures.

'This means they may last longer in the atmosphere."

Atmospheric aerosols are one of the areas of climate science where there are considerable uncertainties. The description covers tiny particles that can be either solid or liquid, ranging from the dusts of the Saharan desert, to soot, to aerosols formed by chemical reaction. These can have a variety of impacts: while most aerosols reflect sunlight back into space, others absorb it.

Aerosols and the clouds seeded by them, are said to reflect about a quarter of the Sun's energy back into space.

Researchers have known for some time that emissions of fatty acid molecules from chip pans and cookers may coat aerosol particles in the atmosphere - but this is the first time that scientists have looked at their role inside droplets.

In their study, the researchers levitated droplets of brine and oleic acid, a fatty acid associated with cooking, said the Daily Mail. They found that the fat molecules assembled into highly structured "lypotropic" phases - crystal-like lattices of spheres or cylinders that are known to affect water uptake.

Further experiments showed that fatty acids in these structures were more resistant to ozone, and so could survive longer and travel further in the atmosphere, said the newspaper.

The findings suggest that the extended lifetimes of these molecules may help clouds to form.

Dr Adam Squires, co-author of the study, said: "We know that the complex structures we saw are formed by similar fatty acid molecules like soap in water.

"There, they dramatically affect whether the mixture is cloudy or transparent, solid or liquid, and how much it absorbs moisture from the atmosphere in a lab.

"The idea that this may also be happening in the air above our heads is exciting, and raises challenges in understanding what these cooking fats are really doing to the world around us."

The researchers hope their findings will encourage more scientists to explore the impact of fats in the atmosphere.

Dr Pfrang added: "It is likely that these structures have a significant effect on water uptake of droplets in the atmosphere, increase lifetimes of reactive molecules and generally slow down transport inside these droplets with yet unexplored consequences."

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