Why moving hot air creates browning
The fan in an air fryer moves hot air around food more actively than still oven air. As the surface dries, it can brown and become firmer. Browning is strongest where hot air can reach directly, which is why perforated crisper plates and open racks are useful. Food that starts with a dry exterior, such as frozen fries or lightly oiled vegetables, generally responds better than food coated in a wet batter. Crispness is not just about heat. The food needs time for surface moisture to leave without the outside scorching. Thick pieces may need a moderate cooking stage to heat through, followed by a hotter finish for browning. If the exterior darkens before the center is ready, lower the temperature and extend the time. If the food is cooked through but pale, a short hotter finish can help.
