Acrylamide formation in fried sweet potatoes: impact of different air-fryer models with different heat transfer systems

Air-frying has gained popularity as a healthier alternative to conventional frying; however, the formation of acrylamide in carbohydrate-rich foods remains a safety concern. This study evaluated the influence of two domestic air-fryer configurations, rotating basket and static basket systems, on thermal performance and acrylamide formation in sweet potatoes (Ipomoea batatas L.). Thermal profiles were characterized under empty and food loaded conditions, and sweet potato strips were air-fried for 5–30 min under comparable thermal conditions. Acrylamide was determined using LC-ESI-MS/MS, and moisture, water activity, weight loss, and color were also evaluated. Acrylamide formation increased progressively with frying time in both devices, although marked differences were observed between the systems. In the rotating basket air-fryer, acrylamide levels ranged from non-detectable values at 5 min to 1854 μg/kg after 30 min. In contrast, the static basket air-fryer produced significantly higher concentrations, ranging from 40 μg/kg at 5 min to 9087 μg/kg at 30 min. The European benchmark for French fries (500 μg/kg) was exceeded after 15 min in the static basket system (683 μg/kg), whereas in the rotating basket device, the levels remained below this value at 20 min, indicating that longer frying times are required to reach it. The higher acrylamide levels observed in the static basket air-fryer may be associated with a higher thermal load, more stable convective heat transfer, and faster surface dehydration. These findings demonstrate that air-fryer design significantly influences acrylamide formation and should be considered when developing safer domestic cooking practices for sweet potatoes.