Experimental Evaluation of Quality Parameters During Drying of Carrot Samples

The aim of this work was to evaluate the effect of operating conditions on the quality of dried foods, monitoring shrinkage, rehydration capacity, and color changes. Carrot samples of different shapes and dimensions were dried in a convective oven by air whose temperature and velocity were chosen in a range of physical significance. Two values of air velocity, i.e., 2.8 and 2.2 m/s, were considered; air temperature was chosen equal to 50 A degrees C, 70 A degrees C, and 85 A degrees C. It was observed that more drastic drying conditions indeed improved the drying rate, but were also responsible for a decrease of food rehydration capacity. Food behavior was observed comparing some characteristic parameters as obtained upon fitting the experimental data by simple modeling equations. In particular, the drying curves were fitted by the Newton's model, whereas, shrinkage was modeled by a linear relationship between volume variation and moisture content. Rehydration capacity was estimated by water regain percentage, which was evaluated after 5 h.