Texture Changes During Drying of Apple Slices

The objective of this study was to investigate the textural changes of apple slices undergoing convective drying. Texture profile analysis (TPA) measurements at 20% compression clearly showed three periods in texture development: softening, uniform hardness, and hardening. In the period of softening, the initial hardness of 2,260 g exponentially decreased to 40–90 g, remained low in the moisture content range of 3.0–0.5 g/g, and rapidly increased below 0.5 g/g. Cohesiveness, springiness, resilience, and chewiness demonstrated similar three-phase behavior with the dependence on moisture content in the period of softening, constant values in the period of uniform hardness, and an inversion point below 0.5 g/g. In the period of hardening, the texture parameters were dependent on temperature.