Abstract:Objective To investigate the effects of deep frying process (DFP), microwave process (MP), and air frying process (AFP) on the quality and aroma characteristics of pre-fried coated tofu.Methods The optimal re-frying conditions are selected using slurry exudation rate, moisture content, color difference, and sensory evaluation as indicators. Subsequently, the re-frying method most suitable for consumers is comprehensively determined based on texture properties, oil content, malondialdehyde content, electronic nose analysis, and volatile compound composition.Results Under the three re-frying methods, the coated tofu exhibits an increase-then-decrease trend in slurry exudation rate and sensory evaluation, accompanied by a continuous decline in moisture content and a gradual shift to yellow color. The optimal conditions for each re-frying process are: 170 ℃ for 30 s in oil (the DFP group), 350 W for 60 s (the MP group), and 170 ℃ for 180 s (the AFP group). Under these optimal conditions, coated tofu in the AFP group exhibits a crispy and golden crust along with a tender and smooth slurry texture. It exhibits hardness and springiness values of 2.47 N and 0.96 mm, respectively, indicating superior overall texture quality compared to the other re-frying processes. Meanwhile, it shows a relatively low fat content of 31.34 g/100 g. Flavor analysis indicates that the AFP group effectively restores the flavor profile of oil re-frying. Furthermore, among the 45 identified volatile compounds, air-fried samples demonstrate high concentrations of alcohols and esters, imparting characteristic oiliness and fruity aromas.Conclusion Air frying offers significant advantages in reducing oil content and improving edible quality.