The influence of drying air temperature on the physical properties of dried and rehydrated eggplant

摘要: Abstract Drying processes generally cause volume and surface change of foodstuffs. Information on the porous structure mechanical properties dried food products is needed for determining quality, process design estimating such as density moisture diffusivity. In this work we investigated structural changes induced in eggplant by convective air drying at four different temperatures (40, 50, 60 70 °C) their effect subsequent rehydration process. kinetic curves were also measured. The physical properties, porosity, pore-size distribution bulk determined Hg porosimetry, scanning electron microscopy optical while textural characteristics dynamometric measurements. As expected, increase temperature causes shorter times. influences strongly microstructure samples: porosity increases with temperature, but better preserved intermediate (60 °C) confirmed lower firmness values respect to other dehydrated samples 50 70 °C). these latter, longer time higher respectively, development a wrinkled structure. particular, 70 °C appears totally broken consequent faster water uptake during rehydration.