Infrared drying of apple slices is an effective method of
water removal. Drying with application of infrared energy is
much faster than convective drying done under equivalent
parameters. Drying kinetics depends on the distance between
infrared energy emitters and the heat-irradiated surface,
and the air velocity as well. The air velocity is an
important variable, since air flowing over the surface cools it
down and lowers its temperature. Hence, the effect of air velocity on kinetics of infrared drying of apple slices is
opposite to that observed during convective drying. Adjusting
distance between infrared emitters and the slice surface
as well as air velocity, a temperature of the material
undergoing drying can be easily controlled. Both short time
of drying and ease of control of material temperature are
advantages of the use of infrared energy in food dehydration.