Influence of the low temperature drying process on optical alternations of organic apple slices

Drying conditions for convective driers are often based on empirical
approaches in which the final product quality is evaluated post processing.
Modern sensor technology and data processing enable second-by-second
quality analyses but conventional systems do not utilize this possibility. An
industrial convective drying chamber was modified with a camera system to
investigate the product during the drying process. The obtained data was
analyzed on color alternation (CIE-L*a*b* color space and Browning Index),
shrinkage and deformation. Both, shrinkage and deformation show minor
dependence on drying conditons. The investigation shows the time depending
optical parameter at different drying conditions. This might offer new "smart"
drying programs with focus on improved product quality.