FOOD. Science. Technology. Quality

Food. SCIENCE. Technology. Quality

Food. Science. TECHNOLOGY. Quality

Food. Science. Technology. QUALITY




Kinetics of water sorption by dried red beet as a method of quality estimation


Under this study, it was researched into the kinetics of water sorption by dried beets produced by the process of convective drying and using infrared radiation. The raw material, after the heat pre-treatment in water vapours, was cut into 5 mm thick, even or grooved slices and into chips. Grooved beet slices were also dried without heat pre-treatment applied. It was proved that the shape of beet pieces and heat treatment impacted both the rate of water sorption and the content of water absorbed by the material after 24 h period of the sorption process. The drying method used caused significant differences in the sorption capacity of water vapour only in the case of chip-shaped beets. The highest water content after 24 h sorption, almost 0.8 g/gdm, was found in the convectively dried chip-shaped beets. In this case, the highest rates of rise in water content were proved irrespective of the water content in the material. Even and grooved beet slices, dried under the conditions of convection, appeared to have to lowest sensitivity to raised humidity in their environment. When no heat treatment was applied prior to drying, the rise in the rate of increase in water content almost doubled and the water content was by 40 % higher after 24 h sorption process.


drying, convection, infrared, kinetics of sorption, red beet