For hot air tunnel drying (HAT), after peeled, pears were
let to dry at a constant temperature of 40 C and an air flow
of 1.2 m s-1 for about 7 days (Fig. 1e). The drying tunnel
was 2 m long, and the air convection was promoted by a
ventilator placed at the entrance of the tunnel. In this
structure, pears were not exposed to light, although the air
was heated by a solar collector, and therefore the sun was
also the main source of energy.