Scientists in Minnesota have reported that commercial cooking is surprisingly a large source of a range of air pollutants that could pose risks to human health and environment.

"While that mouth-watering smell may whet our appetites, it comes from the emission of smoke from the cooking process into the air that we breathe," Deborah Gross of Carleton College said.

Research conducted in the US shows that cooking is by far the largest source of respirable particles generated in the home, as well.

"Exposure to high concentrations of these particles is common," Gross said.

Gross has been working with colleagues Tom Kuehn, Bernard Olson, and Dabrina Dutcher of the University of Minnesota (U-M) to define the specific contribution that commercial cooking makes to air pollution.

Gross and Wang set out to get the chemical signature of the mouth-watering aroma from the cooking process and used a novel combination of chemical and physical measurements of the aerosol particles -- solid and liquid droplets -- emitted from food being cooked.

They conducted the study with typical commercial cooking appliances in a kitchen lab at the U-M during cooking of pizzas in an oven, steaks in a broiler, and hamburgers on a griddle, clamshell broiler, and charcoal fire.

Fatty foods cooked with high heat, especially with open flames, such as cooking hamburger patties on a conveyor broiler, create the most emissions.

Kuehn's previous research has found that for every 1,000 pounds of hamburger cooked on conveyor broilers, 25 pounds of emissions are created.

The same weight of pepperoni pizza cooked in an oven created just three pounds of emissions. The use of certain oils could also increase emissions. For 1,000 pounds of chicken cooked in a wok with peanut oil, 45 pounds of emissions were produced, said an U-M release.

These findings were presented at the 239th National Meeting of the American Chemical Society in San Francisco.