THE ESSENTIAL
- Even cooking high-fat foods in an air fryer produces fewer airborne particles than other cooking methods, such as in a pan or oil fryer.
- However, using the appliance more than 70 times results in a 23% increase in concentrations of cooking-related volatile organic compounds and a more than double increase in ultrafine particle emissions.
- Researchers attribute this phenomenon to the accumulation of residue on the fryer, particularly in areas inaccessible to cleaning.
“Air frying has become a popular low-oil cooking method, but its impact on indoor air pollutant emissions remains poorly understood,” according to researchers at the University of Birmingham (England). This is why they looked into the subject in a study published in the journal ACS ES&T Air. In one experiment, the authors cooked 12 different dishes (frozen foods, fresh foods, high-fat products) in a 4.7-liter air fryer. Then, they focused on emissions of volatile organic compounds, nitrogen oxides and ultrafine particles, all linked to health problems (cardiovascular diseases, lung cancer, etc.). To assess suspended particles emitted during cooking, the team has custom-designed air quality chambers.
Airfryer: emissions remain minimal compared to traditional cooking methods
Emissions of pollutants varied significantly depending on food type, with rates ranging from 17.8 to 184.0 μg per minute for cooking total volatile organic compounds, 24.6 to 37.9 μg per minute for nitrogen oxides, and 0.1 to 17.4 for ultrafine particles, primarily due to Maillard reactions (a chemical reaction between amino acids and sugars). (glucose), contained in food proteins) and the thermal decomposition of lipids. According to the results, foods high in fat, such as onion rings (likely due to being coated in oil before frying), smoked bacon, and unsmoked bacon produced the highest levels of cooking-related ultrafine particle emissions. Although pollutant concentrations and ozone-forming potentials were high inside the chamber, extrapolating them to the volume of a small kitchen indicated levels significantly lower than conventional cooking methods, such as cooking in a pan or in an oil fryer.
Clean the fryer thoroughly to avoid background emissions
However, scientists report that prolonged use without thorough cleaning resulted in background emissions. According to the work, residue accumulating in inaccessible areas of the air fryer after more than 70 uses caused a 23% increase in volatile organic compound concentrations and a 236% increase in ultrafine particle concentrations outside of food cooking.
“Our study shows that repeated use of air fryers, without the ability to clean hard-to-reach cooking surfaces, can negate some of the benefits to indoor air quality. Although emissions are not a concern for families, this finding argues in favor of designing air fryers to allow for thorough cleaning to maintain low emissions over the long term. Air quality in homes and other indoor spaces is increasingly recognized as an important factor, and our work will allow households to better understand the impact of kitchen activities on the quality of the air they breathe at home. said Christian Pfrang, who led the research.
